Split the repeater and link mode audio paths.

This reverts commit 8a1ab88c3a.

AX25Defines.h

@@ -0,0 +1,36 @@
+/*
+ *   Copyright (C) 2020 by Jonathan Naylor G4KLX
+ *
+ *   This program is free software; you can redistribute it and/or modify
+ *   it under the terms of the GNU General Public License as published by
+ *   the Free Software Foundation; either version 2 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ *
+ *   You should have received a copy of the GNU General Public License
+ *   along with this program; if not, write to the Free Software
+ *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#if !defined(AX25DEFINES_H)
+#define  AX25DEFINES_H
+
+const uint8_t AX25_RADIO_SYMBOL_LENGTH = 20U;      // At 24 kHz sample rate
+
+const uint8_t AX25_FRAME_START = 0x7EU;
+const uint8_t AX25_FRAME_END   = 0x7EU;
+const uint8_t AX25_FRAME_ABORT = 0xFEU;
+
+const uint8_t AX25_MAX_ONES    = 5U;
+
+const uint16_t AX25_MIN_FRAME_LENGTH = 17U;        // Callsign (7) + Callsign (7) + Control (1) + Checksum (2)
+
+const uint16_t AX25_MAX_FRAME_LENGTH = 330U;       // Callsign (7) + Callsign (7) + 8 Digipeaters (56) +
+                                                   // Control (1) + PID (1) + Data (256) + Checksum (2)
+
+#endif
+

AX25Demodulator.cpp

@@ -0,0 +1,319 @@
+/*
+ *   Copyright (C) 2020 by Jonathan Naylor G4KLX
+ *   Copyright 2015-2019 Mobilinkd LLC <[email protected]>
+ *
+ *   This program is free software; you can redistribute it and/or modify
+ *   it under the terms of the GNU General Public License as published by
+ *   the Free Software Foundation; either version 2 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ *
+ *   You should have received a copy of the GNU General Public License
+ *   along with this program; if not, write to the Free Software
+ *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include "Config.h"
+
+#if defined(MODE_AX25)
+
+#include "Globals.h"
+#include "AX25Demodulator.h"
+#include "AX25Defines.h"
+
+const float32_t SAMPLE_RATE = 24000.0F;
+const float32_t SYMBOL_RATE = 1200.0F;
+
+const uint16_t DELAY_LEN = 11U;
+
+const float32_t SAMPLES_PER_SYMBOL = SAMPLE_RATE / SYMBOL_RATE;
+const float32_t PLL_LIMIT          = SAMPLES_PER_SYMBOL / 2.0F;
+
+const uint32_t LPF_FILTER_LEN = 48U;
+
+q15_t LPF_FILTER_COEFFS[] = {
+    -2,   -8,  -17,  -28,  -40,  -47,  -47,  -34,
+    -5,   46,  122,  224,  354,  510,  689,  885,
+  1092, 1302, 1506, 1693, 1856, 1987, 2077, 2124,
+  2124, 2077, 1987, 1856, 1693, 1506, 1302, 1092,
+  885,  689,  510,  354,  224,  122,   46,    -5,
+  -34,  -47,  -47,  -40,  -28,  -17,   -8,    -2
+};
+
+// Lock low-pass filter taps (80Hz Bessel)
+// scipy.signal:
+//      b, a = bessel(4, [80.0/(1200/2)], 'lowpass')
+//
+const uint8_t PLL_IIR_SIZE = 5U;
+
+const float32_t PLL_LOCK_B[] = {
+    1.077063e-03,4.308253e-03,6.462379e-03,4.308253e-03,1.077063e-03};
+
+const float32_t PLL_LOCK_A[] = {
+    1.000000e+00,-2.774567e+00,2.962960e+00,-1.437990e+00,2.668296e-01};
+
+// 64 Hz loop filter.
+// scipy.signal:
+//      loop_coeffs = firwin(9, [64.0/(1200/2)], width = None,
+//          pass_zero = True, scale = True, window='hann')
+//
+const uint32_t PLL_FILTER_LEN = 7U;
+
+float32_t PLL_FILTER_COEFFS[] = {3.196252e-02F, 1.204223e-01F, 2.176819e-01F, 2.598666e-01F, 2.176819e-01F, 1.204223e-01F, 3.196252e-02F};
+
+CAX25Demodulator::CAX25Demodulator(int8_t n) :
+m_frame(),
+m_twist(n),
+m_lpfFilter(),
+m_lpfState(),
+m_delayLine(NULL),
+m_delayPos(0U),
+m_nrziState(false),
+m_pllFilter(),
+m_pllState(),
+m_pllLast(false),
+m_pllBits(1U),
+m_pllCount(0.0F),
+m_pllJitter(0.0F),
+m_pllDCD(false),
+m_iirHistory(),
+m_hdlcOnes(0U),
+m_hdlcFlag(false),
+m_hdlcBuffer(0U),
+m_hdlcBits(0U),
+m_hdlcState(AX25_IDLE)
+{
+  m_delayLine = new bool[DELAY_LEN];
+
+  m_lpfFilter.numTaps = LPF_FILTER_LEN;
+  m_lpfFilter.pState  = m_lpfState;
+  m_lpfFilter.pCoeffs = LPF_FILTER_COEFFS;
+
+  m_pllFilter.numTaps = PLL_FILTER_LEN;
+  m_pllFilter.pState  = m_pllState;
+  m_pllFilter.pCoeffs = PLL_FILTER_COEFFS;
+
+  for (uint8_t i = 0U; i < PLL_IIR_SIZE; i++)
+    m_iirHistory[i] = 0.0F;
+}
+
+bool CAX25Demodulator::process(q15_t* samples, uint8_t length, CAX25Frame& frame)
+{
+  bool result = false;
+
+  q15_t fa[RX_BLOCK_SIZE];
+  m_twist.process(samples, fa, RX_BLOCK_SIZE);
+
+  int16_t buffer[RX_BLOCK_SIZE];
+  for (uint8_t i = 0; i < length; i++) {
+      bool   level = (fa[i] >= 0);
+      bool delayed = delay(level);
+      buffer[i] = (int16_t(level ^ delayed) << 1) - 1;
+  }
+
+  q15_t fc[RX_BLOCK_SIZE];
+  ::arm_fir_fast_q15(&m_lpfFilter, buffer, fc, RX_BLOCK_SIZE);
+
+  for (uint8_t i = 0; i < length; i++) {
+    bool bit = fc[i] >= 0;
+    bool sample = PLL(bit);
+
+    if (sample) {
+      // We will only ever get one frame because there are
+      // not enough bits in a block for more than one.
+      if (result) {
+        HDLC(NRZI(bit));
+      } else {
+        result = HDLC(NRZI(bit));
+        if (result) {
+          // Copy the frame data.
+          ::memcpy(frame.m_data, m_frame.m_data, AX25_MAX_PACKET_LEN);
+          frame.m_length = m_frame.m_length;
+          frame.m_fcs    = m_frame.m_fcs;
+          m_frame.m_length = 0U;
+        }
+      }
+    }
+  }
+
+  return result;
+}
+
+bool CAX25Demodulator::delay(bool b)
+{
+  bool r = m_delayLine[m_delayPos];
+
+  m_delayLine[m_delayPos++] = b;
+
+  if (m_delayPos >= DELAY_LEN)
+    m_delayPos = 0U;
+
+  return r;
+}
+
+bool CAX25Demodulator::NRZI(bool b)
+{
+  bool result = (b == m_nrziState);
+
+  m_nrziState = b;
+
+  return result;
+}
+
+bool CAX25Demodulator::PLL(bool input)
+{
+  bool sample = false;
+		
+  if (input != m_pllLast || m_pllBits > 16U) {
+    // Record transition.
+    m_pllLast = input;
+
+    if (m_pllCount > PLL_LIMIT)
+      m_pllCount -= SAMPLES_PER_SYMBOL;
+
+    float32_t adjust = m_pllBits > 16U ? 5.0F : 0.0F;
+    float32_t offset = m_pllCount / float32_t(m_pllBits);
+    float32_t jitter;
+    ::arm_fir_f32(&m_pllFilter, &offset, &jitter, 1U);
+
+    float32_t absOffset = adjust;
+    if (offset < 0.0F)
+      absOffset -= offset;
+    else
+      absOffset += offset;
+    m_pllJitter = iir(absOffset);
+
+    m_pllCount -= jitter / 2.0F;
+    m_pllBits = 1U;
+  } else {
+    if (m_pllCount > PLL_LIMIT) {
+      sample = true;
+      m_pllCount -= SAMPLES_PER_SYMBOL;
+      m_pllBits++;
+    }
+  }
+
+  m_pllCount += 1.0F;
+
+  return sample;
+}
+
+bool CAX25Demodulator::HDLC(bool b)
+{
+  if (m_hdlcOnes == AX25_MAX_ONES) {
+    if (b) {
+      // flag byte
+      m_hdlcFlag = true;
+    } else {
+      // bit stuffing...
+      m_hdlcFlag = false;
+      m_hdlcOnes = 0U;
+      return false;
+    }
+  }
+
+  m_hdlcBuffer >>= 1;
+  m_hdlcBuffer |= b ? 128U : 0U;
+  m_hdlcBits++;                      // Free-running until Sync byte.
+
+  if (b)
+    m_hdlcOnes++;
+  else
+    m_hdlcOnes = 0U;
+
+  if (m_hdlcFlag) {
+    bool result = false;
+
+    switch (m_hdlcBuffer) {
+      case AX25_FRAME_END:
+        if (m_frame.m_length >= AX25_MIN_FRAME_LENGTH) {
+          result = m_frame.checkCRC();
+          if (!result)
+              m_frame.m_length = 0U;
+        } else {
+            m_frame.m_length = 0U;
+        }
+        m_hdlcState = AX25_SYNC;
+        m_hdlcFlag = false;
+        m_hdlcBits = 0U;
+        break;
+
+      case AX25_FRAME_ABORT:
+        // Frame aborted
+        m_frame.m_length = 0U;
+        m_hdlcState = AX25_IDLE;
+        m_hdlcFlag = false;
+        m_hdlcBits = 0U;
+        break;
+
+      default:
+        break;
+    }
+
+    return result;
+  }
+
+  switch (m_hdlcState) {
+    case AX25_IDLE:
+      break;
+
+    case AX25_SYNC:
+      if (m_hdlcBits == 8U) {    // 8th bit.
+        // Start of frame data.
+        m_hdlcState = AX25_RECEIVE;
+        m_frame.append(m_hdlcBuffer);
+        m_hdlcBits = 0U;
+      }
+      break;
+
+    case AX25_RECEIVE:
+      if (m_hdlcBits == 8U) {    // 8th bit.
+        m_frame.append(m_hdlcBuffer);
+        m_hdlcBits = 0U;
+      }
+      break;
+
+    default:
+      break;
+  }
+
+  return false;
+}
+
+void CAX25Demodulator::setTwist(int8_t n)
+{
+  m_twist.setTwist(n);
+}
+
+bool CAX25Demodulator::isDCD()
+{
+  if (m_pllJitter <= (SAMPLES_PER_SYMBOL * 0.03F))
+    m_pllDCD = true;
+  else if (m_pllJitter >= (SAMPLES_PER_SYMBOL * 0.15F))
+    m_pllDCD = false;
+
+  return m_pllDCD;
+}
+
+float32_t CAX25Demodulator::iir(float32_t input)
+{
+  for (int8_t i = int8_t(PLL_IIR_SIZE) - 1; i != 0; i--)
+    m_iirHistory[i] = m_iirHistory[i - 1];
+
+  m_iirHistory[0] = input;
+  for (uint8_t i = 1U; i < PLL_IIR_SIZE; i++)
+    m_iirHistory[0] -= PLL_LOCK_A[i] * m_iirHistory[i];
+
+  float32_t result = 0.0F;
+  for (uint8_t i = 0U; i < PLL_IIR_SIZE; i++)
+    result += PLL_LOCK_B[i] * m_iirHistory[i];
+
+  return result;
+}
+
+#endif
+

AX25Demodulator.h

@@ -0,0 +1,77 @@
+/*
+ *   Copyright (C) 2020 by Jonathan Naylor G4KLX
+ *
+ *   This program is free software; you can redistribute it and/or modify
+ *   it under the terms of the GNU General Public License as published by
+ *   the Free Software Foundation; either version 2 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ *
+ *   You should have received a copy of the GNU General Public License
+ *   along with this program; if not, write to the Free Software
+ *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include "Config.h"
+
+#if defined(MODE_AX25)
+
+#if !defined(AX25Demodulator_H)
+#define  AX25Demodulator_H
+
+#include "AX25Frame.h"
+#include "AX25Twist.h"
+
+enum AX25_STATE {
+  AX25_IDLE,
+  AX25_SYNC,
+  AX25_RECEIVE
+};
+
+class CAX25Demodulator {
+public:
+  CAX25Demodulator(int8_t n);
+
+  bool process(q15_t* samples, uint8_t length, CAX25Frame& frame);
+
+  void setTwist(int8_t n);
+
+  bool isDCD();
+
+private:
+  CAX25Frame           m_frame;
+  CAX25Twist           m_twist;
+  arm_fir_instance_q15 m_lpfFilter;
+  q15_t                m_lpfState[70U];     // NoTaps + BlockSize - 1, 48 + 20 - 1 plus some spare
+  bool*                m_delayLine;
+  uint16_t             m_delayPos;
+  bool                 m_nrziState;
+  arm_fir_instance_f32 m_pllFilter;
+  float32_t            m_pllState[20U];     // NoTaps + BlockSize - 1, 7 + 1 - 1 plus some spare
+  bool                 m_pllLast;
+  uint8_t              m_pllBits;
+  float32_t            m_pllCount;
+  float32_t            m_pllJitter;
+  bool                 m_pllDCD;
+  float32_t            m_iirHistory[5U];
+  uint16_t             m_hdlcOnes;
+  bool                 m_hdlcFlag;
+  uint16_t             m_hdlcBuffer;
+  uint16_t             m_hdlcBits;
+  AX25_STATE           m_hdlcState;
+
+  bool delay(bool b);
+  bool NRZI(bool b);
+  bool PLL(bool b);
+  bool HDLC(bool b);
+  float32_t iir(float32_t input);
+};
+
+#endif
+
+#endif
+

AX25Frame.cpp

@@ -0,0 +1,127 @@
+/*
+ *   Copyright (C) 2020 by Jonathan Naylor G4KLX
+ *
+ *   This program is free software; you can redistribute it and/or modify
+ *   it under the terms of the GNU General Public License as published by
+ *   the Free Software Foundation; either version 2 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ *
+ *   You should have received a copy of the GNU General Public License
+ *   along with this program; if not, write to the Free Software
+ *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include "Config.h"
+
+#if defined(MODE_AX25)
+
+#include "Globals.h"
+#include "AX25Frame.h"
+
+const uint16_t CCITT_TABLE[] = {
+	0x0000,0x1189,0x2312,0x329b,0x4624,0x57ad,0x6536,0x74bf,
+	0x8c48,0x9dc1,0xaf5a,0xbed3,0xca6c,0xdbe5,0xe97e,0xf8f7,
+	0x1081,0x0108,0x3393,0x221a,0x56a5,0x472c,0x75b7,0x643e,
+	0x9cc9,0x8d40,0xbfdb,0xae52,0xdaed,0xcb64,0xf9ff,0xe876,
+	0x2102,0x308b,0x0210,0x1399,0x6726,0x76af,0x4434,0x55bd,
+	0xad4a,0xbcc3,0x8e58,0x9fd1,0xeb6e,0xfae7,0xc87c,0xd9f5,
+	0x3183,0x200a,0x1291,0x0318,0x77a7,0x662e,0x54b5,0x453c,
+	0xbdcb,0xac42,0x9ed9,0x8f50,0xfbef,0xea66,0xd8fd,0xc974,
+	0x4204,0x538d,0x6116,0x709f,0x0420,0x15a9,0x2732,0x36bb,
+	0xce4c,0xdfc5,0xed5e,0xfcd7,0x8868,0x99e1,0xab7a,0xbaf3,
+	0x5285,0x430c,0x7197,0x601e,0x14a1,0x0528,0x37b3,0x263a,
+	0xdecd,0xcf44,0xfddf,0xec56,0x98e9,0x8960,0xbbfb,0xaa72,
+	0x6306,0x728f,0x4014,0x519d,0x2522,0x34ab,0x0630,0x17b9,
+	0xef4e,0xfec7,0xcc5c,0xddd5,0xa96a,0xb8e3,0x8a78,0x9bf1,
+	0x7387,0x620e,0x5095,0x411c,0x35a3,0x242a,0x16b1,0x0738,
+	0xffcf,0xee46,0xdcdd,0xcd54,0xb9eb,0xa862,0x9af9,0x8b70,
+	0x8408,0x9581,0xa71a,0xb693,0xc22c,0xd3a5,0xe13e,0xf0b7,
+	0x0840,0x19c9,0x2b52,0x3adb,0x4e64,0x5fed,0x6d76,0x7cff,
+	0x9489,0x8500,0xb79b,0xa612,0xd2ad,0xc324,0xf1bf,0xe036,
+	0x18c1,0x0948,0x3bd3,0x2a5a,0x5ee5,0x4f6c,0x7df7,0x6c7e,
+	0xa50a,0xb483,0x8618,0x9791,0xe32e,0xf2a7,0xc03c,0xd1b5,
+	0x2942,0x38cb,0x0a50,0x1bd9,0x6f66,0x7eef,0x4c74,0x5dfd,
+	0xb58b,0xa402,0x9699,0x8710,0xf3af,0xe226,0xd0bd,0xc134,
+	0x39c3,0x284a,0x1ad1,0x0b58,0x7fe7,0x6e6e,0x5cf5,0x4d7c,
+	0xc60c,0xd785,0xe51e,0xf497,0x8028,0x91a1,0xa33a,0xb2b3,
+	0x4a44,0x5bcd,0x6956,0x78df,0x0c60,0x1de9,0x2f72,0x3efb,
+	0xd68d,0xc704,0xf59f,0xe416,0x90a9,0x8120,0xb3bb,0xa232,
+	0x5ac5,0x4b4c,0x79d7,0x685e,0x1ce1,0x0d68,0x3ff3,0x2e7a,
+	0xe70e,0xf687,0xc41c,0xd595,0xa12a,0xb0a3,0x8238,0x93b1,
+	0x6b46,0x7acf,0x4854,0x59dd,0x2d62,0x3ceb,0x0e70,0x1ff9,
+	0xf78f,0xe606,0xd49d,0xc514,0xb1ab,0xa022,0x92b9,0x8330,
+	0x7bc7,0x6a4e,0x58d5,0x495c,0x3de3,0x2c6a,0x1ef1,0x0f78 };
+
+CAX25Frame::CAX25Frame(const uint8_t* data, uint16_t length) :
+m_data(),
+m_length(0U),
+m_fcs(0U)
+{
+  for (uint16_t i = 0U; i < length && i < (AX25_MAX_PACKET_LEN - 2U); i++)
+    m_data[m_length++] = data[i];
+}
+
+CAX25Frame::CAX25Frame() :
+m_data(),
+m_length(0U),
+m_fcs(0U)
+{
+}
+
+bool CAX25Frame::append(uint16_t c)
+{
+  if (m_length == AX25_MAX_PACKET_LEN)
+    return false;
+
+  m_data[m_length++] = uint8_t(c);
+
+  return true;
+}
+
+bool CAX25Frame::checkCRC()
+{
+  union {
+    uint16_t crc16;
+    uint8_t  crc8[2U];
+  };
+
+  crc16 = 0xFFFFU;
+  for (uint16_t i = 0U; i < (m_length - 2U); i++)
+    crc16 = uint16_t(crc8[1U]) ^ CCITT_TABLE[crc8[0U] ^ m_data[i]];
+
+  crc16 = ~crc16;
+
+  if (crc8[0U] == m_data[m_length - 2U] && crc8[1U] == m_data[m_length - 1U]) {
+    m_fcs = crc16;
+    return true;
+  } else {
+    return false;
+  }
+}
+
+void CAX25Frame::addCRC()
+{
+  union {
+    uint16_t crc16;
+    uint8_t  crc8[2U];
+  };
+
+  crc16 = 0xFFFFU;
+  for (uint16_t i = 0U; i < m_length; i++)
+    crc16 = uint16_t(crc8[1U]) ^ CCITT_TABLE[crc8[0U] ^ m_data[i]];
+
+  crc16 = ~crc16;
+
+  m_fcs = crc16;
+
+  m_data[m_length++] = crc8[0U];
+  m_data[m_length++] = crc8[1U];
+}
+
+#endif
+

AX25Frame.h

@@ -0,0 +1,47 @@
+/*
+ *   Copyright (C) 2020 by Jonathan Naylor G4KLX
+ *
+ *   This program is free software; you can redistribute it and/or modify
+ *   it under the terms of the GNU General Public License as published by
+ *   the Free Software Foundation; either version 2 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ *
+ *   You should have received a copy of the GNU General Public License
+ *   along with this program; if not, write to the Free Software
+ *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include "Config.h"
+
+#if defined(MODE_AX25)
+
+#if !defined(AX25Frame_H)
+#define  AX25Frame_H
+
+const uint16_t AX25_MAX_PACKET_LEN = 300U;
+
+class CAX25Frame {
+public:
+  CAX25Frame(const uint8_t* data, uint16_t length);
+  CAX25Frame();
+
+  bool append(uint16_t c);
+
+  bool checkCRC();
+
+  void addCRC();
+
+  uint8_t  m_data[AX25_MAX_PACKET_LEN];
+  uint16_t m_length;
+  uint16_t m_fcs;
+};
+
+#endif
+
+#endif
+

AX25RX.cpp

@@ -0,0 +1,211 @@
+/*
+ *   Copyright (C) 2020 by Jonathan Naylor G4KLX
+ *
+ *   This program is free software; you can redistribute it and/or modify
+ *   it under the terms of the GNU General Public License as published by
+ *   the Free Software Foundation; either version 2 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ *
+ *   You should have received a copy of the GNU General Public License
+ *   along with this program; if not, write to the Free Software
+ *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include "Config.h"
+
+#if defined(MODE_AX25)
+
+#include "Globals.h"
+#include "AX25RX.h"
+
+/*
+ * Generated with Scipy Filter, 152 coefficients, 1100-2300Hz bandpass,
+ * Hann window, starting and ending 0 value coefficients removed.
+ *
+ * np.array(
+ *  firwin2(152,
+ *      [
+ *          0.0,
+ *          1000.0/(sample_rate/2),
+ *          1100.0/(sample_rate/2),
+ *          2350.0/(sample_rate/2),
+ *          2500.0/(sample_rate/2),
+ *          1.0
+ *      ],
+ *      [0,0,1,1,0,0],
+ *      antisymmetric = False,
+ *      window='hann') * 32768,
+ *  dtype=int)[10:-10]
+ */
+
+const uint32_t FILTER_LEN = 130U;
+
+q15_t FILTER_COEFFS[] = {
+      5,    12,    18,    21,   19,   11,    -2,   -15,   -25,   -27,
+    -21,   -11,    -3,    -5,  -19,  -43,   -69,   -83,   -73,   -35,
+     27,    98,   155,   180,  163,  109,    39,   -20,   -45,   -26,
+     23,    74,    89,    39,  -81, -247,  -407,  -501,  -480,  -334,
+    -92,   175,   388,   479,  429,  275,    99,     5,    68,   298,
+    626,   913,   994,   740,  115, -791, -1770, -2544, -2847, -2509,
+  -1527,   -76,  1518,  2875, 3653, 3653,  2875,  1518,   -76, -1527,
+  -2509, -2847, -2544, -1770, -791,  115,   740,   994,   913,   626,
+    298,    68,     5,    99,  275,  429,   479,   388,   175,   -92,
+   -334,  -480,  -501,  -407, -247,  -81,    39,    89,    74,    23,
+    -26,   -45,   -20,    39,  109,  163,   180,   155,    98,    27,
+    -35,   -73,   -83,   -69,  -43,  -19,    -5,    -3,   -11,   -21,
+    -27,   -25,   -15,    -2,   11,   19,    21,    18,    12,     5
+};
+
+CAX25RX::CAX25RX() :
+m_filter(),
+m_state(),
+m_demod1(3),
+m_demod2(6),
+m_demod3(9),
+m_lastFCS(0U),
+m_count(0U),
+m_slotTime(30U),
+m_slotCount(0U),
+m_pPersist(128U),
+m_dcd(false),
+m_canTX(false),
+m_x(1U),
+m_a(0xB7U),
+m_b(0x73U),
+m_c(0xF6U)
+{
+  m_filter.numTaps = FILTER_LEN;
+  m_filter.pState  = m_state;
+  m_filter.pCoeffs = FILTER_COEFFS;
+
+  initRand();
+}
+
+void CAX25RX::samples(q15_t* samples, uint8_t length)
+{
+  q15_t output[RX_BLOCK_SIZE];
+  ::arm_fir_fast_q15(&m_filter, samples, output, RX_BLOCK_SIZE);
+
+  m_count++;
+
+  CAX25Frame frame;
+
+  bool ret = m_demod1.process(output, length, frame);
+  if (ret) {
+    if (frame.m_fcs != m_lastFCS || m_count > 2U) {
+      m_lastFCS = frame.m_fcs;
+      m_count   = 0U;
+      serial.writeAX25Data(frame.m_data, frame.m_length - 2U);
+    }
+    DEBUG1("Decoder 1 reported");
+  }
+
+  ret = m_demod2.process(output, length, frame);
+  if (ret) {
+    if (frame.m_fcs != m_lastFCS || m_count > 2U) {
+      m_lastFCS = frame.m_fcs;
+      m_count   = 0U;
+      serial.writeAX25Data(frame.m_data, frame.m_length - 2U);
+    }
+    DEBUG1("Decoder 2 reported");
+  }
+
+  ret = m_demod3.process(output, length, frame);
+  if (ret) {
+    if (frame.m_fcs != m_lastFCS || m_count > 2U) {
+      m_lastFCS = frame.m_fcs;
+      m_count   = 0U;
+      serial.writeAX25Data(frame.m_data, frame.m_length - 2U);
+    }
+    DEBUG1("Decoder 3 reported");
+  }
+
+  m_slotCount += RX_BLOCK_SIZE;
+  if (m_slotCount >= m_slotTime) {
+    m_slotCount = 0U;
+
+    bool dcd1 = m_demod1.isDCD();
+    bool dcd2 = m_demod2.isDCD();
+    bool dcd3 = m_demod3.isDCD();
+    
+    if (dcd1 || dcd2 || dcd3) {
+      if (!m_dcd) {
+        io.setDecode(true);
+        io.setADCDetection(true);
+        m_dcd = true;
+      }
+
+      m_canTX = false;
+    } else {
+      if (m_dcd) {
+        io.setDecode(false);
+        io.setADCDetection(false);
+        m_dcd = false;
+      }
+
+      m_canTX = m_pPersist >= rand();
+    }
+  }
+}
+
+bool CAX25RX::canTX() const
+{
+  return m_canTX;
+}
+
+void CAX25RX::setParams(int8_t twist, uint8_t slotTime, uint8_t pPersist)
+{
+  m_demod1.setTwist(twist - 3);
+  m_demod2.setTwist(twist);
+  m_demod3.setTwist(twist + 3);
+
+  m_slotTime = slotTime * 240U;    // Slot time in samples
+  m_pPersist = pPersist;
+}
+
+// Taken from https://www.electro-tech-online.com/threads/ultra-fast-pseudorandom-number-generator-for-8-bit.124249/
+//X ABC Algorithm Random Number Generator for 8-Bit Devices:
+//This is a small PRNG, experimentally verified to have at least a 50 million byte period
+//by generating 50 million bytes and observing that there were no overapping sequences and repeats.
+//This generator passes serial correlation, entropy , Monte Carlo Pi value, arithmetic mean,
+//And many other statistical tests. This generator may have a period of up to 2^32, but this has
+//not been verified.
+//
+// By XORing 3 bytes into the a,b, and c registers, you can add in entropy from 
+//an external source easily.
+//
+//This generator is free to use, but is not suitable for cryptography due to its short period(by //cryptographic standards) and simple construction. No attempt was made to make this generator 
+// suitable for cryptographic use.
+//
+//Due to the use of a constant counter, the generator should be resistant to latching up.
+//A significant performance gain is had in that the x variable is only ever incremented.
+//
+//Only 4 bytes of ram are needed for the internal state, and generating a byte requires 3 XORs , //2 ADDs, one bit shift right , and one increment. Difficult or slow operations like multiply, etc 
+//were avoided for maximum speed on ultra low power devices.
+
+
+void CAX25RX::initRand() //Can also be used to seed the rng with more entropy during use.
+{
+  m_a = (m_a ^ m_c ^ m_x);
+  m_b = (m_b + m_a);
+  m_c = (m_c + (m_b >> 1) ^ m_a);
+}
+
+uint8_t CAX25RX::rand()
+{
+  m_x++;                           //x is incremented every round and is not affected by any other variable
+
+  m_a = (m_a ^ m_c ^ m_x);         //note the mix of addition and XOR
+  m_b = (m_b + m_a);               //And the use of very few instructions
+  m_c = (m_c + (m_b >> 1) ^ m_a);  //the right shift is to ensure that high-order bits from b can affect  
+
+  return uint8_t(m_c);             //low order bits of other variables
+}
+
+#endif
+

AX25RX.h

@@ -0,0 +1,63 @@
+/*
+ *   Copyright (C) 2020 by Jonathan Naylor G4KLX
+ *
+ *   This program is free software; you can redistribute it and/or modify
+ *   it under the terms of the GNU General Public License as published by
+ *   the Free Software Foundation; either version 2 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ *
+ *   You should have received a copy of the GNU General Public License
+ *   along with this program; if not, write to the Free Software
+ *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include "Config.h"
+
+#if defined(MODE_AX25)
+
+#if !defined(AX25RX_H)
+#define  AX25RX_H
+
+#include "AX25Demodulator.h"
+
+class CAX25RX {
+public:
+  CAX25RX();
+
+  void samples(q15_t* samples, uint8_t length);
+
+  void setParams(int8_t twist, uint8_t slotTime, uint8_t pPersist);
+
+  bool canTX() const;
+
+private:
+  arm_fir_instance_q15 m_filter;
+  q15_t                m_state[160U];    // NoTaps + BlockSize - 1, 130 + 20 - 1 plus some spare
+  CAX25Demodulator     m_demod1;
+  CAX25Demodulator     m_demod2;
+  CAX25Demodulator     m_demod3;
+  uint16_t             m_lastFCS;
+  uint32_t             m_count;
+  uint32_t             m_slotTime;
+  uint32_t             m_slotCount;
+  uint8_t              m_pPersist;
+  bool                 m_dcd;
+  bool                 m_canTX;
+  uint8_t              m_x;
+  uint8_t              m_a;
+  uint8_t              m_b;
+  uint8_t              m_c;
+  
+  void initRand();
+  uint8_t rand();
+};
+
+#endif
+
+#endif
+

AX25TX.cpp

@@ -0,0 +1,191 @@
+/*
+ *   Copyright (C) 2020 by Jonathan Naylor G4KLX
+ *
+ *   This program is free software; you can redistribute it and/or modify
+ *   it under the terms of the GNU General Public License as published by
+ *   the Free Software Foundation; either version 2 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ *
+ *   You should have received a copy of the GNU General Public License
+ *   along with this program; if not, write to the Free Software
+ *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include "Config.h"
+
+#if defined(MODE_AX25)
+
+#include "Globals.h"
+#include "AX25TX.h"
+
+#include "AX25Defines.h"
+#include "AX25Frame.h"
+
+
+const uint8_t START_FLAG[] = { AX25_FRAME_START };
+const uint8_t END_FLAG[]   = { AX25_FRAME_END };
+
+const uint8_t BIT_MASK_TABLE1[] = { 0x80U, 0x40U, 0x20U, 0x10U, 0x08U, 0x04U, 0x02U, 0x01U };
+
+#define WRITE_BIT1(p,i,b) p[(i)>>3] = (b) ? (p[(i)>>3] | BIT_MASK_TABLE1[(i)&7]) : (p[(i)>>3] & ~BIT_MASK_TABLE1[(i)&7])
+#define READ_BIT1(p,i)    (p[(i)>>3] & BIT_MASK_TABLE1[(i)&7])
+
+const uint8_t BIT_MASK_TABLE2[] = { 0x01U, 0x02U, 0x04U, 0x08U, 0x10U, 0x20U, 0x40U, 0x80U };
+
+#define WRITE_BIT2(p,i,b) p[(i)>>3] = (b) ? (p[(i)>>3] | BIT_MASK_TABLE2[(i)&7]) : (p[(i)>>3] & ~BIT_MASK_TABLE2[(i)&7])
+#define READ_BIT2(p,i)    (p[(i)>>3] & BIT_MASK_TABLE2[(i)&7])
+
+const uint16_t AUDIO_TABLE_LEN = 120U;
+
+const q15_t AUDIO_TABLE_DATA[] = {
+  0, 214, 428, 641, 851, 1060, 1265, 1468, 1666, 1859, 2048, 2230, 2407, 2577, 2740, 2896, 3043, 3182, 3313, 3434, 3546, 3649,
+  3741, 3823, 3895, 3955, 4006, 4045, 4073, 4089, 4095, 4089, 4073, 4045, 4006, 3955, 3895, 3823, 3741, 3649, 3546, 3434, 3313,
+  3182, 3043, 2896, 2740, 2577, 2407, 2230, 2048, 1859, 1666, 1468, 1265, 1060, 851, 641, 428, 214, 0, -214, -428, -641, -851,
+  -1060, -1265, -1468, -1666, -1859, -2047, -2230, -2407, -2577, -2740, -2896, -3043, -3182, -3313, -3434, -3546, -3649, -3741,
+  -3823, -3895, -3955, -4006, -4045, -4073, -4089, -4095, -4089, -4073, -4045, -4006, -3955, -3895, -3823, -3741, -3649, -3546,
+  -3434, -3313, -3182, -3043, -2896, -2740, -2577, -2407, -2230, -2047, -1859, -1666, -1468, -1265, -1060, -851, -641, -428, -214
+};
+
+CAX25TX::CAX25TX() :
+m_poBuffer(),
+m_poLen(0U),
+m_poPtr(0U),
+m_txDelay(360U),
+m_tablePtr(0U),
+m_nrzi(false)
+{
+}
+
+void CAX25TX::process()
+{
+  if (m_poLen == 0U)
+    return;
+
+  if (!m_duplex) {
+    if (m_poPtr == 0U) {
+      bool tx = ax25RX.canTX();
+      if (!tx)
+        return;
+    }
+  }
+
+  uint16_t space = io.getSpace();
+
+  while (space > AX25_RADIO_SYMBOL_LENGTH) {
+    bool b = READ_BIT1(m_poBuffer, m_poPtr) != 0U;
+    m_poPtr++;
+
+    writeBit(b);
+
+    space -= AX25_RADIO_SYMBOL_LENGTH;
+
+    if (m_poPtr >= m_poLen) {
+      m_poPtr = 0U;
+      m_poLen = 0U;
+      return;
+    }
+  }
+}
+
+uint8_t CAX25TX::writeData(const uint8_t* data, uint16_t length)
+{
+  CAX25Frame frame(data, length);
+  frame.addCRC();
+
+  m_poLen    = 0U;
+  m_poPtr    = 0U;
+  m_nrzi     = false;
+  m_tablePtr = 0U;
+
+  // Add TX delay
+  for (uint16_t i = 0U; i < m_txDelay; i++, m_poLen++) {
+    bool preamble = NRZI(false);
+    WRITE_BIT1(m_poBuffer, m_poLen, preamble);
+  }
+
+  // Add the Start Flag
+  for (uint16_t i = 0U; i < 8U; i++, m_poLen++) {
+    bool b1 = READ_BIT1(START_FLAG, i) != 0U;
+    bool b2 = NRZI(b1);
+    WRITE_BIT1(m_poBuffer, m_poLen, b2);
+  }
+
+  uint8_t ones = 0U;
+  for (uint16_t i = 0U; i < (frame.m_length * 8U); i++) {
+    bool b1 = READ_BIT2(frame.m_data, i) != 0U;
+    bool b2 = NRZI(b1);
+    WRITE_BIT1(m_poBuffer, m_poLen, b2);
+    m_poLen++;
+
+    if (b1) {
+      ones++;
+      if (ones == AX25_MAX_ONES) {
+        // Bit stuffing
+        bool b = NRZI(false);
+        WRITE_BIT1(m_poBuffer, m_poLen, b);
+        m_poLen++;
+        ones = 0U;
+      }
+    } else {
+      ones = 0U;
+    }
+  }
+
+  // Add the End Flag
+  for (uint16_t i = 0U; i < 8U; i++, m_poLen++) {
+    bool b1 = READ_BIT1(END_FLAG, i) != 0U;
+    bool b2 = NRZI(b1);
+    WRITE_BIT1(m_poBuffer, m_poLen, b2);
+  }
+
+  return 0U;
+}
+
+void CAX25TX::writeBit(bool b)
+{
+  q15_t buffer[AX25_RADIO_SYMBOL_LENGTH];
+  for (uint8_t i = 0U; i < AX25_RADIO_SYMBOL_LENGTH; i++) {
+    q15_t value = AUDIO_TABLE_DATA[m_tablePtr];
+
+    if (b) {
+      // De-emphasise the lower frequency by 6dB
+      value >>= 2;
+      m_tablePtr += 6U;
+    } else {
+      m_tablePtr += 11U;
+    }
+
+    buffer[i] = value;
+
+    if (m_tablePtr >= AUDIO_TABLE_LEN)
+      m_tablePtr -= AUDIO_TABLE_LEN;
+  }
+
+  io.write(STATE_AX25, buffer, AX25_RADIO_SYMBOL_LENGTH);
+}
+
+void CAX25TX::setTXDelay(uint8_t delay)
+{
+  m_txDelay = delay * 12U;
+}
+
+uint8_t CAX25TX::getSpace() const
+{
+  return m_poLen == 0U ? 255U : 0U;
+}
+
+bool CAX25TX::NRZI(bool b)
+{
+    if (!b)
+      m_nrzi = !m_nrzi;
+
+    return m_nrzi;
+}
+
+#endif
+

AX25TX.h

@@ -0,0 +1,53 @@
+/*
+ *   Copyright (C) 2020 by Jonathan Naylor G4KLX
+ *
+ *   This program is free software; you can redistribute it and/or modify
+ *   it under the terms of the GNU General Public License as published by
+ *   the Free Software Foundation; either version 2 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ *
+ *   You should have received a copy of the GNU General Public License
+ *   along with this program; if not, write to the Free Software
+ *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include "Config.h"
+
+#if defined(MODE_AX25)
+
+#if !defined(AX25TX_H)
+#define  AX25TX_H
+
+class CAX25TX {
+public:
+  CAX25TX();
+
+  uint8_t writeData(const uint8_t* data, uint16_t length);
+
+  void process();
+
+  void setTXDelay(uint8_t delay);
+
+  uint8_t getSpace() const;
+
+private:
+  uint8_t    m_poBuffer[600U];
+  uint16_t   m_poLen;
+  uint16_t   m_poPtr;
+  uint16_t   m_txDelay;
+  uint16_t   m_tablePtr;
+  bool       m_nrzi;
+
+  void writeBit(bool b);
+  bool NRZI(bool b);
+};
+
+#endif
+
+#endif
+

AX25Twist.cpp

@@ -0,0 +1,316 @@
+/*
+ *   Copyright (C) 2020 by Jonathan Naylor G4KLX
+ *
+ *   This program is free software; you can redistribute it and/or modify
+ *   it under the terms of the GNU General Public License as published by
+ *   the Free Software Foundation; either version 2 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ *
+ *   You should have received a copy of the GNU General Public License
+ *   along with this program; if not, write to the Free Software
+ *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include "Config.h"
+
+#if defined(MODE_AX25)
+
+#include "Globals.h"
+#include "AX25Twist.h"
+
+// 1200Hz = -12dB, 2200Hz = 0dB; 3381Hz cutoff; cosine.
+q15_t dB12[] = {
+  176,
+  -812,
+  -3916,
+  -7586,
+  23536,
+  -7586,
+  -3916,
+  -812,
+  176
+};
+
+// 1200Hz = -11dB, 2200Hz = 0dB; 3258Hz cutoff; cosine.
+q15_t dB11[] = {
+  121,
+  -957,
+  -3959,
+  -7383,
+  23871,
+  -7383,
+  -3959,
+  -957,
+  121
+};
+
+// 1200Hz = -10dB, 2200Hz = 0dB; 3118Hz cutoff; cosine.
+q15_t dB10[] = {
+  56,
+  -1110,
+  -3987,
+  -7141,
+  24254,
+  -7141,
+  -3987,
+  -1110,
+  56
+};
+
+// 1200Hz = -9dB, 2200Hz = 0dB; 2959Hz cutoff; cosine.
+q15_t dB9[] = {
+  -19,
+  -1268,
+  -3994,
+  -6856,
+  24688,
+  -6856,
+  -3994,
+  -1268,
+  -19
+};
+
+// 1200Hz = -8dB, 2200Hz = 0dB; 2778Hz cutoff; cosine.
+q15_t dB8[] = {
+  -104,
+  -1424,
+  -3968,
+  -6516,
+  25182,
+  -6516,
+  -3968,
+  -1424,
+  -104
+};
+
+// 1200Hz = -7dB, 2200Hz = 0dB; 2573Hz cutoff; cosine.
+q15_t dB7[] = {
+  -196,
+  -1565,
+  -3896,
+  -6114,
+  25742,
+  -6114,
+  -3896,
+  -1565,
+  -196
+};
+
+// 1200Hz = -6dB, 2200Hz = 0dB; 2343Hz cutoff; cosine.
+q15_t dB6[] = {
+  -288,
+  -1676,
+  -3761,
+  -5642,
+  26370,
+  -5642,
+  -3761,
+  -1676,
+  -288
+};
+
+// 1200Hz = -5dB, 2200Hz = 0dB; 2085Hz cutoff; cosine.
+q15_t dB5[] = {
+  -370,
+  -1735,
+  -3545,
+  -5088,
+  27075,
+  -5088,
+  -3545,
+  -1735,
+  -370
+};
+
+// 1200Hz = -4dB, 2200Hz = 0dB; 1790Hz cutoff; cosine.
+q15_t dB4[] = {
+  -432,
+  -1715,
+  -3220,
+  -4427,
+  27880,
+  -4427,
+  -3220,
+  -1715,
+  -432
+};
+
+// 1200Hz = -3dB, 2200Hz = 0dB; 1456Hz cutoff; cosine.
+q15_t dB3[] = {
+  -452,
+  -1582,
+  -2759,
+  -3646,
+  28792,
+  -3646,
+  -2759,
+  -1582,
+  -452
+};
+
+// 1200Hz = -2dB, 2200Hz = 0dB; 1070Hz cutoff; cosine.
+q15_t dB2[] = {
+  -408,
+  -1295,
+  -2123,
+  -2710,
+  29846,
+  -2710,
+  -2123,
+  -1295,
+  -408
+};
+
+// 1200Hz = -1dB, 2200Hz = 0dB; 605Hz cutoff; cosine.
+q15_t dB1[] = {
+  -268,
+  -795,
+  -1244,
+  -1546,
+  31116,
+  -1546,
+  -1244,
+  -795,
+  -268
+};
+
+q15_t dB0[] = {
+  0,
+  0,
+  0,
+  0,
+  32767,
+  0,
+  0,
+  0,
+  0,
+};
+
+// 1200Hz = 0dB, 2200Hz = -1dB; 4130Hz cutoff; cosine.
+q15_t dB_1[] = {
+  -419,
+  -177,
+  3316,
+  8650,
+  11278,
+  8650,
+  3316,
+  -177,
+  -419
+};
+
+// 1200Hz = 0dB, 2200Hz = -2dB; 3190Hz cutoff; cosine.
+q15_t dB_2[] = {
+  -90,
+  1033,
+  3975,
+  7267,
+  8711,
+  7267,
+  3975,
+  1033,
+  -90
+};
+
+// 1200Hz = 0dB, 2200Hz = -3dB; 2330Hz cutoff; cosine.
+q15_t dB_3[] = {
+  292,
+  1680,
+  3752,
+  5615,
+  6362,
+  5615,
+  3752,
+  1680,
+  292
+};
+
+// 1200Hz = 0dB, 2200Hz = -4dB; 2657Hz cutoff; boxcar.
+q15_t dB_4[] = {
+  917,
+  3024,
+  5131,
+  6684,
+  7255,
+  6684,
+  5131,
+  3024,
+  917
+};
+
+// 1200Hz = 0dB, 2200Hz = -5dB; 2360Hz cutoff; boxcar.
+q15_t dB_5[] = {
+  1620,
+  3339,
+  4925,
+  6042,
+  6444,
+  6042,
+  4925,
+  3339,
+  1620
+};
+
+// 1200Hz = 0dB, 2200Hz = -6dB; 2067Hz cutoff; boxcar.
+q15_t dB_6[] = {
+  2161,
+  3472,
+  4605,
+  5373,
+  5644,
+  5373,
+  4605,
+  3472,
+  2161
+};
+
+q15_t* coeffs[] = {
+  dB12,
+  dB11,
+  dB10,
+  dB9,
+  dB8,
+  dB7,
+  dB6,
+  dB5,
+  dB4,
+  dB3,
+  dB2,
+  dB1,
+  dB0,
+  dB_1,
+  dB_2,
+  dB_3,
+  dB_4,
+  dB_5,
+  dB_6
+};
+
+CAX25Twist::CAX25Twist(int8_t n) :
+m_filter(),
+m_state()
+{
+  setTwist(n);
+}
+
+void CAX25Twist::process(q15_t* in, q15_t* out, uint8_t length)
+{
+  ::arm_fir_fast_q15(&m_filter, in, out, length);
+}
+
+void CAX25Twist::setTwist(int8_t n)
+{
+  uint8_t twist = uint8_t(n + 6);
+
+  m_filter.numTaps = 9;
+  m_filter.pState  = m_state;
+  m_filter.pCoeffs = coeffs[twist];
+}
+
+#endif
+

AX25Twist.h

@@ -0,0 +1,42 @@
+/*
+ *   Copyright (C) 2020 by Jonathan Naylor G4KLX
+ *
+ *   This program is free software; you can redistribute it and/or modify
+ *   it under the terms of the GNU General Public License as published by
+ *   the Free Software Foundation; either version 2 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ *
+ *   You should have received a copy of the GNU General Public License
+ *   along with this program; if not, write to the Free Software
+ *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include "Config.h"
+
+#if defined(MODE_AX25)
+
+#if !defined(AX25Twist_H)
+#define  AX25Twist_H
+
+class CAX25Twist {
+public:
+  CAX25Twist(int8_t n);
+
+  void process(q15_t* in, q15_t* out, uint8_t length);
+
+  void setTwist(int8_t n);
+
+private:
+  arm_fir_instance_q15 m_filter;
+  q15_t                m_state[40U];   // NoTaps + BlockSize - 1, 9 + 20 - 1 plus some spare
+};
+
+#endif
+
+#endif
+

CWIdTX.cpp

@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2009-2017 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2009-2017,2020 by Jonathan Naylor G4KLX
  *   Copyright (C) 2016 by Colin Durbridge G4EML
  *
  *   This program is free software; you can redistribute it and/or modify
@@ -125,7 +125,7 @@ void CCWIdTX::process()
   }
 }
 
-uint8_t CCWIdTX::write(const uint8_t* data, uint8_t length)
+uint8_t CCWIdTX::write(const uint8_t* data, uint16_t length)
 {
   ::memset(m_poBuffer, 0x00U, 1000U * sizeof(uint8_t));
 

CWIdTX.h

@@ -1,6 +1,6 @@
 /*
  *   Copyright (C) 2009-2015 by Jonathan Naylor G4KLX
- *   Copyright (C) 2016 by Colin Durbridge G4EML
+ *   Copyright (C) 2016,2020 by Colin Durbridge G4EML
  *
  *   This program is free software; you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
@@ -28,7 +28,7 @@ public:
 
   void process();
 
-  uint8_t write(const uint8_t* data, uint8_t length);
+  uint8_t write(const uint8_t* data, uint16_t length);
 
   void reset();
 

CalDMR.cpp

@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2009-2015 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2009-2015,2020 by Jonathan Naylor G4KLX
  *   Copyright (C) 2016 by Colin Durbridge G4EML
  *
  *   This program is free software; you can redistribute it and/or modify
@@ -18,6 +18,9 @@
  */
 
 #include "Config.h"
+
+#if defined(MODE_DMR)
+
 #include "Globals.h"
 #include "CalDMR.h"
 
@@ -208,7 +211,7 @@ void CCalDMR::dmrdmo1k()
   }
 }
 
-uint8_t CCalDMR::write(const uint8_t* data, uint8_t length)
+uint8_t CCalDMR::write(const uint8_t* data, uint16_t length)
 {
   if (length != 1U)
     return 4U;
@@ -221,3 +224,5 @@ uint8_t CCalDMR::write(const uint8_t* data, uint8_t length)
   return 0U;
 }
 
+#endif
+

CalDMR.h

@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2009-2015 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2009-2015,2020 by Jonathan Naylor G4KLX
  *   Copyright (C) 2016 by Colin Durbridge G4EML
  *
  *   This program is free software; you can redistribute it and/or modify
@@ -17,10 +17,13 @@
  *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  */
 
+#include "Config.h"
+
+#if defined(MODE_DMR)
+
 #if !defined(CALDMR_H)
 #define  CALDMR_H
 
-#include "Config.h"
 #include "DMRDefines.h"
 
 enum DMRCAL1K {
@@ -41,7 +44,7 @@ public:
   void createData1k(uint8_t n);
   void createDataDMO1k(uint8_t n);
 
-  uint8_t write(const uint8_t* data, uint8_t length);
+  uint8_t write(const uint8_t* data, uint16_t length);
 
 private:
   bool      m_transmit;
@@ -53,3 +56,5 @@ private:
 
 #endif
 
+#endif
+

CalDStarRX.cpp

@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2009-2016 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2009-2016,2020 by Jonathan Naylor G4KLX
  *
  *   This program is free software; you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
@@ -17,6 +17,9 @@
  */
 
 #include "Config.h"
+
+#if defined(MODE_DSTAR)
+
 #include "Globals.h"
 #include "CalDStarRX.h"
 #include "Utils.h"
@@ -24,7 +27,7 @@
 const unsigned int BUFFER_LENGTH = 200U;
 
 const uint32_t PLLMAX = 0x10000U;
-const uint32_t PLLINC = PLLMAX / DSTAR_RADIO_BIT_LENGTH;
+const uint32_t PLLINC = PLLMAX / DSTAR_RADIO_SYMBOL_LENGTH;
 const uint32_t INC    = PLLINC / 32U;
 
 // D-Star bit order version of 0x55 0x2D 0x16
@@ -126,3 +129,5 @@ void CCalDStarRX::process(q15_t value)
   }
 }
 
+#endif
+

CalDStarRX.h

@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2015,2016 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2015,2016,2020 by Jonathan Naylor G4KLX
  *
  *   This program is free software; you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
@@ -16,10 +16,13 @@
  *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  */
 
+#include "Config.h"
+
+#if defined(MODE_DSTAR)
+
 #if !defined(CALDSTARRX_H)
 #define  CALDSTARRX_H
 
-#include "Config.h"
 #include "DStarDefines.h"
 
 class CCalDStarRX {
@@ -40,3 +43,5 @@ private:
 
 #endif
 
+#endif
+

CalDStarTX.cpp

@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2009-2016 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2009-2016,2020 by Jonathan Naylor G4KLX
  *
  *   This program is free software; you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
@@ -17,6 +17,9 @@
  */
 
 #include "Config.h"
+
+#if defined(MODE_DSTAR)
+
 #include "Globals.h"
 #include "CalDStarTX.h"
 
@@ -162,7 +165,7 @@ void CCalDStarTX::process()
   m_count = (m_count + 1U) % (30U * 21U);
 }
 
-uint8_t CCalDStarTX::write(const uint8_t* data, uint8_t length)
+uint8_t CCalDStarTX::write(const uint8_t* data, uint16_t length)
 {
   if (length != 1U)
     return 4U;
@@ -181,3 +184,5 @@ uint8_t CCalDStarTX::write(const uint8_t* data, uint8_t length)
   return 0U;
 }
 
+#endif
+

CalDStarTX.h

@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2015,2016 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2015,2016,2020 by Jonathan Naylor G4KLX
  *
  *   This program is free software; you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
@@ -16,17 +16,20 @@
  *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  */
 
+#include "Config.h"
+
+#if defined(MODE_DSTAR)
+
 #if !defined(CALDSTARTX_H)
 #define  CALDSTARTX_H
 
-#include "Config.h"
 #include "DStarDefines.h"
 
 class CCalDStarTX {
 public:
   CCalDStarTX();
 
-  uint8_t write(const uint8_t* data, uint8_t length);
+  uint8_t write(const uint8_t* data, uint16_t length);
 
   void process();
 
@@ -37,3 +40,5 @@ private:
 
 #endif
 
+#endif
+

CalFM.cpp

@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2009-2015 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2009-2015,2020 by Jonathan Naylor G4KLX
  *   Copyright (C) 2016 by Colin Durbridge G4EML
  *   Copyright (C) 2020 by Phil Taylor M0VSE
  *
@@ -19,6 +19,9 @@
  */
 
 #include "Config.h"
+
+#if defined(MODE_FM)
+
 #include "Globals.h"
 #include "CalFM.h"
 
@@ -41,7 +44,7 @@ CCalFM::CCalFM() :
 m_frequency(0),
 m_length(0),
 m_tone(NULL),
-m_level(128*32),
+m_level(128 * 12),
 m_transmit(false),
 m_audioSeq(0),
 m_lastState(STATE_IDLE)
@@ -52,29 +55,29 @@ void CCalFM::process()
 {
   const TONE_TABLE* entry = NULL;
 
-  if (m_modemState!=m_lastState)
+  if (m_modemState != m_lastState)
   {
     switch (m_modemState) {
         case STATE_FMCAL10K:
-          m_frequency=956U;
+          m_frequency = 956U;
           break;
         case STATE_FMCAL12K:
-          m_frequency=1039U;
+          m_frequency = 1039U;
           break;
         case STATE_FMCAL15K:
-          m_frequency=1247U;
+          m_frequency = 1247U;
           break;
         case STATE_FMCAL20K:
-          m_frequency=1633U;
+          m_frequency = 1633U;
           break;
         case STATE_FMCAL25K:
-          m_frequency=2079U;
+          m_frequency = 2079U;
           break;
         case STATE_FMCAL30K:
-          m_frequency=2495U;
+          m_frequency = 2495U;
           break;
         default:
-          m_frequency=0;
+          m_frequency = 0U;
           break;
     }
 
@@ -116,7 +119,7 @@ void CCalFM::process()
 }
 
 
-uint8_t CCalFM::write(const uint8_t* data, uint8_t length)
+uint8_t CCalFM::write(const uint8_t* data, uint16_t length)
 {
   if (length != 1U)
     return 4U;
@@ -125,3 +128,6 @@ uint8_t CCalFM::write(const uint8_t* data, uint8_t length)
 
   return 0U;
 }
+
+#endif
+

CalFM.h

@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2009-2015 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2009-2015,2020 by Jonathan Naylor G4KLX
  *   Copyright (C) 2016 by Colin Durbridge G4EML
  *   Copyright (C) 2020 by Phil Taylor M0VSE
  *
@@ -18,11 +18,13 @@
  *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  */
 
+#include "Config.h"
+
+#if defined(MODE_FM)
+
 #if !defined(CALFM_H)
 #define  CALFM_H
 
-#include "Config.h"
-
 class CCalFM {
 public:
   CCalFM();
@@ -35,7 +37,7 @@ public:
   void fm25kcal();
   void fm30kcal();
 
-  uint8_t write(const uint8_t* data, uint8_t length);
+  uint8_t write(const uint8_t* data, uint16_t length);
 
 private:
   uint16_t  m_frequency;
@@ -49,3 +51,5 @@ private:
 
 #endif
 
+#endif
+

CalNXDN.cpp

@@ -1,5 +1,6 @@
 /*
  *   Copyright (C) 2018 by Andy Uribe CA6JAU
+ *   Copyright (C) 2020 by Jonathan Naylor G4KLX
  *
  *   This program is free software; you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
@@ -17,6 +18,9 @@
  */
 
 #include "Config.h"
+
+#if defined(MODE_NXDN)
+
 #include "Globals.h"
 #include "CalNXDN.h"
 
@@ -79,7 +83,7 @@ void CCalNXDN::process()
   }
 }
 
-uint8_t CCalNXDN::write(const uint8_t* data, uint8_t length)
+uint8_t CCalNXDN::write(const uint8_t* data, uint16_t length)
 {
   if (length != 1U)
     return 4U;
@@ -92,3 +96,5 @@ uint8_t CCalNXDN::write(const uint8_t* data, uint8_t length)
   return 0U;
 }
 
+#endif
+

CalNXDN.h

@@ -1,5 +1,6 @@
 /*
  *   Copyright (C) 2018 by Andy Uribe CA6JAU
+ *   Copyright (C) 2020 by Jonathan Naylor G4KLX
  *
  *   This program is free software; you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
@@ -16,11 +17,13 @@
  *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  */
 
+#include "Config.h"
+
+#if defined(MODE_NXDN)
+
 #if !defined(CALNXDN_H)
 #define  CALNXDN_H
 
-#include "Config.h"
-
 enum NXDNCAL1K {
   NXDNCAL1K_IDLE,
   NXDNCAL1K_TX
@@ -32,7 +35,7 @@ public:
 
   void process();
 
-  uint8_t write(const uint8_t* data, uint8_t length);
+  uint8_t write(const uint8_t* data, uint16_t length);
 
 private:
   bool      m_transmit;
@@ -42,3 +45,5 @@ private:
 
 #endif
 
+#endif
+

CalP25.cpp

@@ -1,5 +1,6 @@
 /*
  *   Copyright (C) 2018 by Andy Uribe CA6JAU
+ *   Copyright (C) 2020 by Jonathan Naylor G4KLX
  *
  *   This program is free software; you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
@@ -17,6 +18,9 @@
  */
 
 #include "Config.h"
+
+#if defined(MODE_P25)
+
 #include "Globals.h"
 #include "CalP25.h"
 
@@ -82,7 +86,7 @@ void CCalP25::process()
   }
 }
 
-uint8_t CCalP25::write(const uint8_t* data, uint8_t length)
+uint8_t CCalP25::write(const uint8_t* data, uint16_t length)
 {
   if (length != 1U)
     return 4U;
@@ -95,3 +99,5 @@ uint8_t CCalP25::write(const uint8_t* data, uint8_t length)
   return 0U;
 }
 
+#endif
+

CalP25.h

@@ -1,5 +1,6 @@
 /*
  *   Copyright (C) 2018 by Andy Uribe CA6JAU
+ *   Copyright (C) 2020 by Jonathan Naylor G4KLX
  *
  *   This program is free software; you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
@@ -16,10 +17,13 @@
  *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  */
 
+#include "Config.h"
+
+#if defined(MODE_P25)
+
 #if !defined(CALP25_H)
 #define  CALP25_H
 
-#include "Config.h"
 #include "P25Defines.h"
 
 enum P25CAL1K {
@@ -34,7 +38,7 @@ public:
 
   void process();
 
-  uint8_t write(const uint8_t* data, uint8_t length);
+  uint8_t write(const uint8_t* data, uint16_t length);
 
 private:
   bool      m_transmit;
@@ -43,3 +47,5 @@ private:
 
 #endif
 
+#endif
+

CalPOCSAG.cpp

@@ -1,5 +1,6 @@
 /*
  *   Copyright (C) 2019 by Florian Wolters DF2ET
+ *   Copyright (C) 2020 by Jonathan Naylor G4KLX
  *
  *   This program is free software; you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
@@ -17,10 +18,12 @@
  */
 
 #include "Config.h"
+
+#if defined(MODE_POCSAG)
+
 #include "Globals.h"
 #include "CalPOCSAG.h"
 
-
 CCalPOCSAG::CCalPOCSAG() :
 m_state(POCSAGCAL_IDLE)
 {
@@ -38,7 +41,7 @@ void CCalPOCSAG::process()
   pocsagTX.writeByte(0xAAU);
 }
 
-uint8_t CCalPOCSAG::write(const uint8_t* data, uint8_t length)
+uint8_t CCalPOCSAG::write(const uint8_t* data, uint16_t length)
 {
   if (length != 1U)
     return 4U;
@@ -47,3 +50,6 @@ uint8_t CCalPOCSAG::write(const uint8_t* data, uint8_t length)
 
   return 0U;
 }
+
+#endif
+

CalPOCSAG.h

@@ -1,5 +1,6 @@
 /*
  *   Copyright (C) 2019 by Florian Wolters DF2ET
+ *   Copyright (C) 2020 by Jonathan Naylor G4KLX
  *
  *   This program is free software; you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
@@ -16,11 +17,13 @@
  *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  */
 
+#include "Config.h"
+
+#if defined(MODE_POCSAG)
+
 #if !defined(CALPOCSAG_H)
 #define  CALPOCSAG_H
 
-#include "Config.h"
-
 enum POCSAGCAL {
   POCSAGCAL_IDLE,
   POCSAGCAL_TX
@@ -32,10 +35,13 @@ public:
 
   void process();
 
-  uint8_t write(const uint8_t* data, uint8_t length);
+  uint8_t write(const uint8_t* data, uint16_t length);
 
 private:
   POCSAGCAL m_state;
 };
 
 #endif
+
+#endif
+

Config.h

@@ -19,6 +19,37 @@
 #if !defined(CONFIG_H)
 #define  CONFIG_H
 
+// Allow for the selection of which modes to compile into the firmware. This is particularly useful for processors
+// which have limited code space and processing power like the STM32F103, which is found on older/cheaper boards.
+
+// Enable D-Star support.
+#define MODE_DSTAR
+
+// Enable DMR support.
+#define MODE_DMR
+
+// Enable System Fusion support.
+#define MODE_YSF
+
+// Enable P25 phase 1 support.
+#define MODE_P25
+
+// Enable NXDN support, the boxcar filter sometimes improves the performance of NXDN receive on some systems.
+#define MODE_NXDN
+#define USE_NXDN_BOXCAR
+
+// Enable M17 support.
+#define MODE_M17
+
+// Enable POCSAG support.
+#define MODE_POCSAG
+
+// Enable FM support.
+#define MODE_FM
+
+// Enable AX.25 support, this is only enabled if FM is also enabled.
+#define MODE_AX25
+
 // Allow for the use of high quality external clock oscillators
 // The number is the frequency of the oscillator in Hertz.
 //
@@ -35,11 +66,16 @@
 // For 19.2 MHz
 // #define EXTERNAL_OSC 19200000
 
+// Select a baud rate for host communication. The faster speeds are needed for external FM to work.
+// #define SERIAL_SPEED 115200 // Suitable for most older boards (Arduino Due, STM32F1_POG, etc). External FM will NOT work with this!
+// #define SERIAL_SPEED 230400 // Only works on newer boards like fast M4, M7, Teensy 3.x. External FM might work with this
+#define SERIAL_SPEED 460800	// Only works on newer boards like fast M4, M7, Teensy 3.x. External FM should work with this
+
 // Allow the use of the COS line to lockout the modem
 // #define USE_COS_AS_LOCKOUT
 
 // Use pins to output the current mode via LEDs
-// #define MODE_LEDS
+#define MODE_LEDS
 
 // For the original Arduino Due pin layout
 // #define ARDUINO_DUE_PAPA
@@ -49,7 +85,7 @@
 #define STM32F1_POG
 #else
 // For the ZUM V1.0 and V1.0.1 boards pin layout
-#define ARDUINO_DUE_ZUM_V10
+// #define ARDUINO_DUE_ZUM_V10
 #endif
 
 // For the SP8NTH board
@@ -66,10 +102,13 @@
 // #define VK6MST_TEENSY_PI3_SHIELD_I2C
 
 // Pass RSSI information to the host
-// #define SEND_RSSI_DATA
+#define SEND_RSSI_DATA
 
 // Use the modem as a serial repeater for Nextion displays
-// #define SERIAL_REPEATER
+#define SERIAL_REPEATER
+
+// Use the modem as an I2C repeater for OLED displays
+// #define I2C_REPEATER
 
 // To reduce CPU load, you can remove the DC blocker by commenting out the next line
 #define USE_DCBLOCKER
@@ -81,10 +120,20 @@
 // Use the YSF and P25 LEDs for NXDN
 // #define USE_ALTERNATE_NXDN_LEDS
 
+// Use the D-Star and P25 LEDs for M17
+#define USE_ALTERNATE_M17_LEDS
+
 // Use the D-Star and DMR LEDs for POCSAG
-// #define USE_ALTERNATE_POCSAG_LEDS
+#define USE_ALTERNATE_POCSAG_LEDS
 
 // Use the D-Star and YSF LEDs for FM
 #define USE_ALTERNATE_FM_LEDS
 
+#if defined(STM32F1_POG)
+// Slower boards need to run their serial at 115200 baud
+#undef SERIAL_SPEED
+#define SERIAL_SPEED 115200
 #endif
+
+#endif
+

DMRDMORX.cpp

@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2009-2017 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2009-2017,2020 by Jonathan Naylor G4KLX
  *
  *   This program is free software; you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
@@ -17,6 +17,9 @@
  */
 
 #include "Config.h"
+
+#if defined(MODE_DMR)
+
 #include "Globals.h"
 #include "DMRDMORX.h"
 #include "DMRSlotType.h"
@@ -423,3 +426,6 @@ void CDMRDMORX::writeRSSIData(uint8_t* frame)
   serial.writeDMRData(true, frame, DMR_FRAME_LENGTH_BYTES + 1U);
 #endif
 }
+
+#endif
+

DMRDMORX.h

@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2015,2016,2017 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2015,2016,2017,2020 by Jonathan Naylor G4KLX
  *
  *   This program is free software; you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
@@ -16,10 +16,13 @@
  *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  */
 
+#include "Config.h"
+
+#if defined(MODE_DMR)
+
 #if !defined(DMRDMORX_H)
 #define  DMRDMORX_H
 
-#include "Config.h"
 #include "DMRDefines.h"
 
 const uint16_t DMO_BUFFER_LENGTH_SAMPLES = 1440U;   // 60ms at 24 kHz
@@ -67,3 +70,6 @@ private:
 };
 
 #endif
+
+#endif
+

DMRDMOTX.cpp

@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2009-2017 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2009-2017,2020 by Jonathan Naylor G4KLX
  *   Copyright (C) 2016 by Colin Durbridge G4EML
  *   Copyright (C) 2017 by Andy Uribe CA6JAU
  *
@@ -19,6 +19,9 @@
  */
 
 #include "Config.h"
+
+#if defined(MODE_DMR)
+
 #include "Globals.h"
 #include "DMRSlotType.h"
 
@@ -74,7 +77,7 @@ void CDMRDMOTX::process()
       m_poLen = m_txDelay;
     } else {
       for (unsigned int i = 0U; i < DMR_FRAME_LENGTH_BYTES; i++)
-        m_poBuffer[i] = m_fifo.get();
+        m_fifo.get(m_poBuffer[i]);
 
       for (unsigned int i = 0U; i < 39U; i++)
         m_poBuffer[i + DMR_FRAME_LENGTH_BYTES] = PR_FILL[i];
@@ -104,7 +107,7 @@ void CDMRDMOTX::process()
   }
 }
 
-uint8_t CDMRDMOTX::writeData(const uint8_t* data, uint8_t length)
+uint8_t CDMRDMOTX::writeData(const uint8_t* data, uint16_t length)
 {
   if (length != (DMR_FRAME_LENGTH_BYTES + 1U))
     return 4U;
@@ -161,3 +164,5 @@ void CDMRDMOTX::setTXDelay(uint8_t delay)
     m_txDelay = 1200U;
 }
 
+#endif
+

DMRDMOTX.h

@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2015,2016,2017 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2015,2016,2017,2020 by Jonathan Naylor G4KLX
  *   Copyright (C) 2016 by Colin Durbridge G4EML
  *
  *   This program is free software; you can redistribute it and/or modify
@@ -17,19 +17,22 @@
  *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  */
 
+#include "Config.h"
+
+#if defined(MODE_DMR)
+
 #if !defined(DMRDMOTX_H)
 #define  DMRDMOTX_H
 
-#include "Config.h"
 #include "DMRDefines.h"
 
-#include "SerialRB.h"
+#include "RingBuffer.h"
 
 class CDMRDMOTX {
 public:
   CDMRDMOTX();
 
-  uint8_t writeData(const uint8_t* data, uint8_t length);
+  uint8_t writeData(const uint8_t* data, uint16_t length);
 
   void process();
 
@@ -38,7 +41,7 @@ public:
   uint8_t getSpace() const;
 
 private:
-  CSerialRB                        m_fifo;
+  CRingBuffer<uint8_t>                        m_fifo;
   arm_fir_interpolate_instance_q15 m_modFilter;
   q15_t                            m_modState[16U];    // blockSize + phaseLength - 1, 4 + 9 - 1 plus some spare
   uint8_t                          m_poBuffer[1200U];
@@ -51,3 +54,5 @@ private:
 
 #endif
 
+#endif
+

DMRIdleRX.cpp

@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2009-2017 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2009-2017,2020 by Jonathan Naylor G4KLX
  *
  *   This program is free software; you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
@@ -17,6 +17,9 @@
  */
 
 #include "Config.h"
+
+#if defined(MODE_DMR)
+
 #include "Globals.h"
 #include "DMRIdleRX.h"
 #include "DMRSlotType.h"
@@ -209,3 +212,6 @@ void CDMRIdleRX::setColorCode(uint8_t colorCode)
 {
   m_colorCode = colorCode;
 }
+
+#endif
+

DMRIdleRX.h

@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2015 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2015,2020 by Jonathan Naylor G4KLX
  *
  *   This program is free software; you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
@@ -16,10 +16,13 @@
  *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  */
 
+#include "Config.h"
+
+#if defined(MODE_DMR)
+
 #if !defined(DMRIDLERX_H)
 #define  DMRIDLERX_H
 
-#include "Config.h"
 #include "DMRDefines.h"
 
 class CDMRIdleRX {
@@ -49,3 +52,5 @@ private:
 
 #endif
 
+#endif
+

DMRRX.cpp

@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2015,2016 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2015,2016,2020 by Jonathan Naylor G4KLX
  *
  *   This program is free software; you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
@@ -17,6 +17,9 @@
  */
 
 #include "Config.h"
+
+#if defined(MODE_DMR)
+
 #include "Globals.h"
 #include "DMRRX.h"
 
@@ -68,3 +71,5 @@ void CDMRRX::reset()
   m_slot2RX.reset();
 }
 
+#endif
+

DMRRX.h

@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2015,2016 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2015,2016,2020 by Jonathan Naylor G4KLX
  *
  *   This program is free software; you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
@@ -16,10 +16,13 @@
  *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  */
 
+#include "Config.h"
+
+#if defined(MODE_DMR)
+
 #if !defined(DMRRX_H)
 #define  DMRRX_H
 
-#include "Config.h"
 #include "DMRSlotRX.h"
 
 class CDMRRX {
@@ -40,3 +43,5 @@ private:
 
 #endif
 
+#endif
+

DMRSlotRX.cpp

@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2009-2017 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2009-2017,2020 by Jonathan Naylor G4KLX
  *
  *   This program is free software; you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
@@ -17,6 +17,9 @@
  */
 
 #include "Config.h"
+
+#if defined(MODE_DMR)
+
 #include "Globals.h"
 #include "DMRSlotRX.h"
 #include "DMRSlotType.h"
@@ -400,3 +403,6 @@ void CDMRSlotRX::writeRSSIData(uint8_t* frame)
   serial.writeDMRData(m_slot, frame, DMR_FRAME_LENGTH_BYTES + 1U);
 #endif
 }
+
+#endif
+

DMRSlotRX.h

@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2015,2016,2017 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2015,2016,2017,2020 by Jonathan Naylor G4KLX
  *
  *   This program is free software; you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
@@ -16,10 +16,13 @@
  *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  */
 
+#include "Config.h"
+
+#if defined(MODE_DMR)
+
 #if !defined(DMRSLOTRX_H)
 #define  DMRSLOTRX_H
 
-#include "Config.h"
 #include "DMRDefines.h"
 
 enum DMRRX_STATE {
@@ -70,3 +73,6 @@ private:
 };
 
 #endif
+
+#endif
+

DMRSlotType.cpp

@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2015 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2015,2020 by Jonathan Naylor G4KLX
  *
  *   This program is free software; you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
@@ -17,6 +17,9 @@
  */
 
 #include "Config.h"
+
+#if defined(MODE_DMR)
+
 #include "Globals.h"
 #include "DMRSlotType.h"
 
@@ -285,3 +288,5 @@ void CDMRSlotType::encode(uint8_t colorCode, uint8_t dataType, uint8_t* frame) c
   frame[20U] = (frame[20U] & 0x03U) | ((slotType[1U] << 6) & 0xC0U) | ((slotType[2U] >> 2) & 0x3CU);
 }
 
+#endif
+

DMRSlotType.h

@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2015 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2015,2020 by Jonathan Naylor G4KLX
  *
  *   This program is free software; you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
@@ -16,6 +16,10 @@
  *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  */
 
+#include "Config.h"
+
+#if defined(MODE_DMR)
+
 #if !defined(DMRSLOTTYPE_H)
 #define  DMRSLOTTYPE_H
 
@@ -35,3 +39,5 @@ private:
 
 #endif
 
+#endif
+

DMRTX.cpp

@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2009-2017 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2009-2017,2020 by Jonathan Naylor G4KLX
  *   Copyright (C) 2016 by Colin Durbridge G4EML
  *   Copyright (C) 2017 by Andy Uribe CA6JAU
  *
@@ -19,6 +19,9 @@
  */
 
 #include "Config.h"
+
+#if defined(MODE_DMR)
+
 #include "Globals.h"
 #include "DMRSlotType.h"
 
@@ -144,7 +147,7 @@ void CDMRTX::process()
   }
 }
 
-uint8_t CDMRTX::writeData1(const uint8_t* data, uint8_t length)
+uint8_t CDMRTX::writeData1(const uint8_t* data, uint16_t length)
 {
   if (length != (DMR_FRAME_LENGTH_BYTES + 1U))
     return 4U;
@@ -168,7 +171,7 @@ uint8_t CDMRTX::writeData1(const uint8_t* data, uint8_t length)
   return 0U;
 }
 
-uint8_t CDMRTX::writeData2(const uint8_t* data, uint8_t length)
+uint8_t CDMRTX::writeData2(const uint8_t* data, uint16_t length)
 {
   if (length != (DMR_FRAME_LENGTH_BYTES + 1U))
     return 4U;
@@ -192,7 +195,7 @@ uint8_t CDMRTX::writeData2(const uint8_t* data, uint8_t length)
   return 0U;
 }
 
-uint8_t CDMRTX::writeShortLC(const uint8_t* data, uint8_t length)
+uint8_t CDMRTX::writeShortLC(const uint8_t* data, uint16_t length)
 {
   if (length != 9U)
     return 4U;
@@ -208,7 +211,7 @@ uint8_t CDMRTX::writeShortLC(const uint8_t* data, uint8_t length)
   return 0U;
 }
 
-uint8_t CDMRTX::writeAbort(const uint8_t* data, uint8_t length)
+uint8_t CDMRTX::writeAbort(const uint8_t* data, uint16_t length)
 {
   if (length != 1U)
     return 4U;
@@ -293,7 +296,7 @@ void CDMRTX::createData(uint8_t slotIndex)
 {
   if (m_fifo[slotIndex].getData() >= DMR_FRAME_LENGTH_BYTES && m_frameCount >= STARTUP_COUNT && m_abortCount[slotIndex] >= ABORT_COUNT) {
     for (unsigned int i = 0U; i < DMR_FRAME_LENGTH_BYTES; i++) {
-      m_poBuffer[i]   = m_fifo[slotIndex].get();
+      m_fifo[slotIndex].get(m_poBuffer[i]);
       m_markBuffer[i] = MARK_NONE;
     }
   } else {
@@ -414,3 +417,6 @@ uint32_t CDMRTX::getFrameCount()
 {
   return m_frameCount;
 }
+
+#endif
+

DMRTX.h

@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2015,2016,2017 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2015,2016,2017,2020 by Jonathan Naylor G4KLX
  *   Copyright (C) 2016 by Colin Durbridge G4EML
  *
  *   This program is free software; you can redistribute it and/or modify
@@ -17,13 +17,16 @@
  *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  */
 
+#include "Config.h"
+
+#if defined(MODE_DMR)
+
 #if !defined(DMRTX_H)
 #define  DMRTX_H
 
-#include "Config.h"
 #include "DMRDefines.h"
 
-#include "SerialRB.h"
+#include "RingBuffer.h"
 
 enum DMRTXSTATE {
   DMRTXSTATE_IDLE,
@@ -38,11 +41,11 @@ class CDMRTX {
 public:
   CDMRTX();
 
-  uint8_t writeData1(const uint8_t* data, uint8_t length);
-  uint8_t writeData2(const uint8_t* data, uint8_t length);
+  uint8_t writeData1(const uint8_t* data, uint16_t length);
+  uint8_t writeData2(const uint8_t* data, uint16_t length);
 
-  uint8_t writeShortLC(const uint8_t* data, uint8_t length);
-  uint8_t writeAbort(const uint8_t* data, uint8_t length);
+  uint8_t writeShortLC(const uint8_t* data, uint16_t length);
+  uint8_t writeAbort(const uint8_t* data, uint16_t length);
 
   void setStart(bool start);
   void setCal(bool start);
@@ -59,7 +62,7 @@ public:
   void setColorCode(uint8_t colorCode);
 
 private:
-  CSerialRB                        m_fifo[2U];
+  CRingBuffer<uint8_t>                        m_fifo[2U];
   arm_fir_interpolate_instance_q15 m_modFilter;
   q15_t                            m_modState[16U];    // blockSize + phaseLength - 1, 4 + 9 - 1 plus some spare
   DMRTXSTATE                       m_state;
@@ -83,3 +86,5 @@ private:
 
 #endif
 
+#endif
+

DStarDefines.h

@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2009-2015 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2009-2015,2017,2020 by Jonathan Naylor G4KLX
  *
  *   This program is free software; you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
@@ -19,30 +19,50 @@
 #if !defined(DSTARDEFINES_H)
 #define  DSTARDEFINES_H
 
-const unsigned int DSTAR_RADIO_BIT_LENGTH = 5U;      // At 24 kHz sample rate
+const unsigned int DSTAR_RADIO_SYMBOL_LENGTH = 5U;      // At 24 kHz sample rate
 
-const unsigned int DSTAR_HEADER_LENGTH_BYTES = 41U;
-const unsigned int DSTAR_HEADER_LENGTH_BITS  = DSTAR_HEADER_LENGTH_BYTES * 8U;
+const unsigned int DSTAR_HEADER_LENGTH_BYTES   = 41U;
 
-const unsigned int DSTAR_FEC_SECTION_LENGTH_BYTES = 83U;
-const unsigned int DSTAR_FEC_SECTION_LENGTH_BITS  = 660U;
+const unsigned int DSTAR_FEC_SECTION_LENGTH_BYTES   = 83U;
+const unsigned int DSTAR_FEC_SECTION_LENGTH_SYMBOLS = 660U;
+const unsigned int DSTAR_FEC_SECTION_LENGTH_SAMPLES = DSTAR_FEC_SECTION_LENGTH_SYMBOLS * DSTAR_RADIO_SYMBOL_LENGTH;
 
-const unsigned int DSTAR_DATA_LENGTH_BYTES = 12U;
-const unsigned int DSTAR_DATA_LENGTH_BITS  = DSTAR_DATA_LENGTH_BYTES * 8U;
+const unsigned int DSTAR_DATA_LENGTH_BYTES   = 12U;
+const unsigned int DSTAR_DATA_LENGTH_SYMBOLS = DSTAR_DATA_LENGTH_BYTES * 8U;
+const unsigned int DSTAR_DATA_LENGTH_SAMPLES = DSTAR_DATA_LENGTH_SYMBOLS * DSTAR_RADIO_SYMBOL_LENGTH;
 
-const uint8_t      DSTAR_EOT_BYTES[] = {0x55, 0x55, 0x55, 0x55, 0xC8, 0x7A, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00};
-const unsigned int DSTAR_EOT_LENGTH_BYTES = 6U;
-const unsigned int DSTAR_EOT_LENGTH_BITS  = DSTAR_EOT_LENGTH_BYTES * 8U;
+const unsigned int DSTAR_END_SYNC_LENGTH_BYTES = 6U;
+const unsigned int DSTAR_END_SYNC_LENGTH_BITS  = DSTAR_END_SYNC_LENGTH_BYTES * 8U;
 
-const uint8_t      DSTAR_DATA_SYNC_LENGTH_BYTES = 3U;
-const uint8_t      DSTAR_DATA_SYNC_LENGTH_BITS  = DSTAR_DATA_SYNC_LENGTH_BYTES * 8U;
+const unsigned int DSTAR_FRAME_SYNC_LENGTH_BYTES   = 3U;
+const unsigned int DSTAR_FRAME_SYNC_LENGTH_SYMBOLS = DSTAR_FRAME_SYNC_LENGTH_BYTES * 8U;
+const unsigned int DSTAR_FRAME_SYNC_LENGTH_SAMPLES = DSTAR_FRAME_SYNC_LENGTH_SYMBOLS * DSTAR_RADIO_SYMBOL_LENGTH;
 
-const uint8_t      DSTAR_DATA_SYNC_BYTES[] = {0x9E, 0x8D, 0x32, 0x88, 0x26, 0x1A, 0x3F, 0x61, 0xE8, 0x55, 0x2D, 0x16};
+const unsigned int DSTAR_DATA_SYNC_LENGTH_BYTES   = 3U;
+const unsigned int DSTAR_DATA_SYNC_LENGTH_SYMBOLS = DSTAR_DATA_SYNC_LENGTH_BYTES * 8U;
+const unsigned int DSTAR_DATA_SYNC_LENGTH_SAMPLES = DSTAR_DATA_SYNC_LENGTH_SYMBOLS * DSTAR_RADIO_SYMBOL_LENGTH;
 
-const uint8_t      DSTAR_SLOW_DATA_TYPE_TEXT   = 0x40U;
-const uint8_t      DSTAR_SLOW_DATA_TYPE_HEADER = 0x50U;
+const uint8_t DSTAR_DATA_SYNC_BYTES[] = {0x9E, 0x8D, 0x32, 0x88, 0x26, 0x1A, 0x3F, 0x61, 0xE8, 0x55, 0x2D, 0x16};
 
-const uint8_t      DSTAR_SCRAMBLER_BYTES[] = {0x70U, 0x4FU, 0x93U};
+// D-Star bit order version of 0x55 0x6E 0x0A
+const uint32_t DSTAR_FRAME_SYNC_DATA = 0x00557650U;
+const uint32_t DSTAR_FRAME_SYNC_MASK = 0x00FFFFFFU;
+const bool     DSTAR_FRAME_SYNC_SYMBOLS[] = {false, true, false, true, false, true, false, true, false, true, true, true, false, true, true, false, false, true, false, true, false, false, false, false};
+
+// D-Star bit order version of 0x55 0x2D 0x16
+const uint32_t DSTAR_DATA_SYNC_DATA = 0x00AAB468U;
+const uint32_t DSTAR_DATA_SYNC_MASK = 0x00FFFFFFU;
+const bool     DSTAR_DATA_SYNC_SYMBOLS[] = {true, false, true, false, true, false, true, false, true, false, true, true, false, true, false, false, false, true, true, false, true, false, false, false};
+
+// D-Star bit order version of 0x55 0x55 0xC8 0x7A
+const uint32_t DSTAR_END_SYNC_DATA = 0xAAAA135EU;
+const uint32_t DSTAR_END_SYNC_MASK = 0xFFFFFFFFU;
+const uint8_t  DSTAR_END_SYNC_BYTES[] = {0x55, 0x55, 0x55, 0x55, 0xC8, 0x7A, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00};
+
+const uint8_t  DSTAR_SLOW_DATA_TYPE_TEXT   = 0x40U;
+const uint8_t  DSTAR_SLOW_DATA_TYPE_HEADER = 0x50U;
+
+const uint8_t  DSTAR_SCRAMBLER_BYTES[] = {0x70U, 0x4FU, 0x93U};
 
 #endif
 

DStarRX.cpp

@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2009-2017 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2009-2017,2020 by Jonathan Naylor G4KLX
  *   Copyright (C) 2017 by Andy Uribe CA6JAU
  *
  *   This program is free software; you can redistribute it and/or modify
@@ -18,31 +18,28 @@
  */
 
 #include "Config.h"
+
+#if defined(MODE_DSTAR)
+
 #include "Globals.h"
 #include "DStarRX.h"
 #include "Utils.h"
 
-const unsigned int BUFFER_LENGTH = 200U;
-
-const uint32_t PLLMAX = 0x10000U;
-const uint32_t PLLINC = PLLMAX / DSTAR_RADIO_BIT_LENGTH;
-const uint32_t INC    = PLLINC / 32U;
-
-const unsigned int MAX_SYNC_BITS = 100U * DSTAR_DATA_LENGTH_BITS;
+const unsigned int MAX_FRAMES = 150U;
 
 // D-Star bit order version of 0x55 0x55 0x6E 0x0A
-const uint32_t FRAME_SYNC_DATA = 0x00557650U;
-const uint32_t FRAME_SYNC_MASK = 0x00FFFFFFU;
+const uint64_t FRAME_SYNC_DATA = 0x0000000000557650U;
+const uint64_t FRAME_SYNC_MASK = 0x0000000000FFFFFFU;
 const uint8_t  FRAME_SYNC_ERRS = 2U;
 
 // D-Star bit order version of 0x55 0x2D 0x16
-const uint32_t DATA_SYNC_DATA = 0x00AAB468U;
-const uint32_t DATA_SYNC_MASK = 0x00FFFFFFU;
+const uint64_t DATA_SYNC_DATA = 0x0000000000AAB468U;
+const uint64_t DATA_SYNC_MASK = 0x0000000000FFFFFFU;
 const uint8_t  DATA_SYNC_ERRS = 2U;
 
 // D-Star bit order version of 0x55 0x55 0xC8 0x7A
-const uint32_t END_SYNC_DATA = 0xAAAA135EU;
-const uint32_t END_SYNC_MASK = 0xFFFFFFFFU;
+const uint64_t END_SYNC_DATA = 0x0000AAAAAAAA135EU;
+const uint64_t END_SYNC_MASK = 0x0000FFFFFFFFFFFFU;
 const uint8_t  END_SYNC_ERRS = 1U;
 
 const uint8_t BIT_MASK_TABLE0[] = {0x7FU, 0xBFU, 0xDFU, 0xEFU, 0xF7U, 0xFBU, 0xFDU, 0xFEU};
@@ -237,14 +234,24 @@ const uint16_t CCITT_TABLE[] = {
   0xf78fU, 0xe606U, 0xd49dU, 0xc514U, 0xb1abU, 0xa022U, 0x92b9U, 0x8330U,
   0x7bc7U, 0x6a4eU, 0x58d5U, 0x495cU, 0x3de3U, 0x2c6aU, 0x1ef1U, 0x0f78U};
 
+const uint16_t NOENDPTR = 9999U;
+
 CDStarRX::CDStarRX() :
-m_pll(0U),
-m_prev(false),
 m_rxState(DSRXS_NONE),
-m_patternBuffer(0x00U),
-m_rxBuffer(),
-m_rxBufferBits(0U),
-m_dataBits(0U),
+m_bitBuffer(),
+m_headerBuffer(),
+m_dataBuffer(),
+m_bitPtr(0U),
+m_headerPtr(0U),
+m_dataPtr(0U),
+m_startPtr(NOENDPTR),
+m_syncPtr(NOENDPTR),
+m_minSyncPtr(NOENDPTR),
+m_maxSyncPtr(NOENDPTR),
+m_maxFrameCorr(0),
+m_maxDataCorr(0),
+m_frameCount(0U),
+m_countdown(0U),
 m_mar(0U),
 m_pathMetric(),
 m_pathMemory0(),
@@ -259,14 +266,20 @@ m_rssiCount(0U)
 
 void CDStarRX::reset()
 {
-  m_pll           = 0U;
-  m_prev          = false;
-  m_rxState       = DSRXS_NONE;
-  m_patternBuffer = 0x00U;
-  m_rxBufferBits  = 0U;
-  m_dataBits      = 0U;
-  m_rssiAccum     = 0U;
-  m_rssiCount     = 0U;
+  m_rxState      = DSRXS_NONE;
+  m_headerPtr    = 0U;
+  m_dataPtr      = 0U;
+  m_bitPtr       = 0U;
+  m_maxFrameCorr = 0;
+  m_maxDataCorr  = 0;
+  m_startPtr     = NOENDPTR;
+  m_syncPtr      = NOENDPTR;
+  m_minSyncPtr   = NOENDPTR;
+  m_maxSyncPtr   = NOENDPTR;
+  m_frameCount   = 0U;
+  m_countdown    = 0U;
+  m_rssiAccum    = 0U;
+  m_rssiCount    = 0U;
 }
 
 void CDStarRX::samples(const q15_t* samples, const uint16_t* rssi, uint8_t length)
@@ -275,125 +288,117 @@ void CDStarRX::samples(const q15_t* samples, const uint16_t* rssi, uint8_t lengt
     m_rssiAccum += rssi[i];
     m_rssiCount++;
 
-    bool bit = samples[i] < 0;
+    q15_t sample = samples[i];
 
-    if (bit != m_prev) {
-      if (m_pll < (PLLMAX / 2U))
-        m_pll += INC;
-      else
-        m_pll -= INC;
+    m_bitBuffer[m_bitPtr] <<= 1;
+    if (sample < 0)
+      m_bitBuffer[m_bitPtr] |= 0x01U;
+
+    m_dataBuffer[m_dataPtr] = sample;
+
+    switch (m_rxState) {
+      case DSRXS_HEADER:
+        processHeader(sample);
+        break;
+      case DSRXS_DATA:
+        processData();
+        break;
+      default:
+        processNone(sample);
+        break;
     }
 
-    m_prev = bit;
+    m_dataPtr++;
+    if (m_dataPtr >= DSTAR_DATA_LENGTH_SAMPLES)
+      m_dataPtr = 0U;
 
-    m_pll += PLLINC;
-
-    if (m_pll >= PLLMAX) {
-      m_pll -= PLLMAX;
-
-      switch (m_rxState) {
-        case DSRXS_NONE:
-          processNone(bit);
-          break;
-        case DSRXS_HEADER:
-          processHeader(bit);
-          break;
-        case DSRXS_DATA:
-          processData(bit);
-          break;
-        default:
-          break;
-      }
-    }
+    m_bitPtr++;
+    if (m_bitPtr >= DSTAR_RADIO_SYMBOL_LENGTH)
+      m_bitPtr = 0U;
   }
 }
 
-void CDStarRX::processNone(bool bit)
+void CDStarRX::processNone(q15_t sample)
 {
-  m_patternBuffer <<= 1;
-  if (bit)
-    m_patternBuffer |= 0x01U;
-
   // Fuzzy matching of the frame sync sequence
-  if (countBits32((m_patternBuffer & FRAME_SYNC_MASK) ^ FRAME_SYNC_DATA) <= FRAME_SYNC_ERRS) {
-    DEBUG1("DStarRX: found frame sync in None");
+  bool ret = correlateFrameSync();
+  if (ret) {
+    m_countdown = 5U;
 
-    ::memset(m_rxBuffer, 0x00U, DSTAR_FEC_SECTION_LENGTH_BYTES);
-    m_rxBufferBits = 0U;
+    m_headerBuffer[m_headerPtr] = sample;
+    m_headerPtr++;
 
     m_rssiAccum = 0U;
     m_rssiCount = 0U;
 
     m_rxState = DSRXS_HEADER;
+
     return;
   }
 
-  // Exact matching of the data sync bit sequence
-  if (countBits32((m_patternBuffer & DATA_SYNC_MASK) ^ DATA_SYNC_DATA) == 0U) {
+  // Fuzzy matching of the data sync bit sequence
+  ret = correlateDataSync();
+  if (ret) {
     DEBUG1("DStarRX: found data sync in None");
 
     io.setDecode(true);
     io.setADCDetection(true);
 
-    // Suppress RSSI on the dummy sync message
-    m_rssiAccum = 0U;
-    m_rssiCount = 0U;
-
-    ::memcpy(m_rxBuffer, DSTAR_DATA_SYNC_BYTES, DSTAR_DATA_LENGTH_BYTES);
-    writeRSSIData(m_rxBuffer);
-
-    ::memset(m_rxBuffer, 0x00U, DSTAR_DATA_LENGTH_BYTES + 2U);
-    m_rxBufferBits = 0U;
-
-    m_dataBits  = MAX_SYNC_BITS;
-    m_rxState   = DSRXS_DATA;
-    return;
+    m_rxState = DSRXS_DATA;
   }
 }
 
-void CDStarRX::processHeader(bool bit)
+void CDStarRX::processHeader(q15_t sample)
 {
-  m_patternBuffer <<= 1;
-  if (bit)
-    m_patternBuffer |= 0x01U;
+  if (m_countdown > 0U) {
+    correlateFrameSync();
+    m_countdown--;
+  }
 
-  WRITE_BIT2(m_rxBuffer, m_rxBufferBits, bit);
-  m_rxBufferBits++;
+  m_headerBuffer[m_headerPtr] = sample;
+  m_headerPtr++;
 
   // A full FEC header
-  if (m_rxBufferBits == DSTAR_FEC_SECTION_LENGTH_BITS) {
-    // Process the scrambling, interleaving and FEC, then return if the chcksum was correct
-    unsigned char header[DSTAR_HEADER_LENGTH_BYTES];
-    bool ok = rxHeader(m_rxBuffer, header);
-    if (ok) {
+  if (m_headerPtr == (DSTAR_FEC_SECTION_LENGTH_SAMPLES + DSTAR_RADIO_SYMBOL_LENGTH)) {
+    uint8_t buffer[DSTAR_FEC_SECTION_LENGTH_BYTES];
+    samplesToBits(m_headerBuffer, DSTAR_RADIO_SYMBOL_LENGTH, DSTAR_FEC_SECTION_LENGTH_SYMBOLS, buffer, DSTAR_FEC_SECTION_LENGTH_SAMPLES);
+
+    // Process the scrambling, interleaving and FEC, then return true if the chcksum was correct
+    uint8_t header[DSTAR_HEADER_LENGTH_BYTES];
+    bool ok = rxHeader(buffer, header);
+    if (!ok) {
+      // The checksum failed, return to looking for syncs
+      m_rxState = DSRXS_NONE;
+      m_maxFrameCorr = 0;
+      m_maxDataCorr  = 0;
+    } else {
       io.setDecode(true);
       io.setADCDetection(true);
 
       writeRSSIHeader(header);
-
-      ::memset(m_rxBuffer, 0x00U, DSTAR_DATA_LENGTH_BYTES + 2U);
-      m_rxBufferBits = 0U;
-
-      m_rxState  = DSRXS_DATA;
-      m_dataBits = MAX_SYNC_BITS;
-    } else {
-      // The checksum failed, return to looking for syncs
-      m_rxState = DSRXS_NONE;
     }
   }
+
+  // Ready to start the first data section
+  if (m_headerPtr == (DSTAR_FEC_SECTION_LENGTH_SAMPLES + 2U * DSTAR_RADIO_SYMBOL_LENGTH)) {
+    m_frameCount = 0U;
+    m_dataPtr    = 0U;
+
+    m_startPtr   = 476U;
+    m_syncPtr    = 471U;
+    m_maxSyncPtr = 472U;
+    m_minSyncPtr = 470U;
+
+    DEBUG5("DStarRX: calc start/sync/max/min", m_startPtr, m_syncPtr, m_maxSyncPtr, m_minSyncPtr);
+
+    m_rxState = DSRXS_DATA;
+  }
 }
 
-void CDStarRX::processData(bool bit)
+void CDStarRX::processData()
 {
-  m_patternBuffer <<= 1;
-  if (bit)
-    m_patternBuffer |= 0x01U;
-
-  WRITE_BIT2(m_rxBuffer, m_rxBufferBits, bit);
-  m_rxBufferBits++;
-
   // Fuzzy matching of the end frame sequences
-  if (countBits32((m_patternBuffer & END_SYNC_MASK) ^ END_SYNC_DATA) <= END_SYNC_ERRS) {
+  if (countBits64((m_bitBuffer[m_bitPtr] & DSTAR_END_SYNC_MASK) ^ DSTAR_END_SYNC_DATA) <= END_SYNC_ERRS) {
     DEBUG1("DStarRX: Found end sync in Data");
 
     io.setDecode(false);
@@ -401,35 +406,24 @@ void CDStarRX::processData(bool bit)
 
     serial.writeDStarEOT();
 
+    m_maxFrameCorr = 0;
+    m_maxDataCorr  = 0;
+
     m_rxState = DSRXS_NONE;
     return;
   }
 
   // Fuzzy matching of the data sync bit sequence
-  bool syncSeen = false;
-  if (m_rxBufferBits >= (DSTAR_DATA_LENGTH_BITS - 3U)) {
-    if (countBits32((m_patternBuffer & DATA_SYNC_MASK) ^ DATA_SYNC_DATA) <= DATA_SYNC_ERRS) {
-      m_rxBufferBits = DSTAR_DATA_LENGTH_BITS;
-      m_dataBits     = MAX_SYNC_BITS;
-      syncSeen       = true;
-    }
+  if (m_minSyncPtr < m_maxSyncPtr) {
+    if (m_dataPtr >= m_minSyncPtr && m_dataPtr <= m_maxSyncPtr)
+      correlateDataSync();
+  } else {
+    if (m_dataPtr >= m_minSyncPtr || m_dataPtr <= m_maxSyncPtr)
+      correlateDataSync();
   }
 
-  // Check to see if the sync is arriving late
-  if (m_rxBufferBits == DSTAR_DATA_LENGTH_BITS && !syncSeen) {
-    for (uint8_t i = 1U; i <= 3U; i++) {
-      uint32_t syncMask = DATA_SYNC_MASK >> i;
-      uint32_t syncData = DATA_SYNC_DATA >> i;
-      if (countBits32((m_patternBuffer & syncMask) ^ syncData) <= DATA_SYNC_ERRS) {
-        m_rxBufferBits -= i;
-        break;
-      }
-    }
-  }
-
-  m_dataBits--;
-
-  if (m_dataBits == 0U) {
+  // We've not seen a data sync for too long, signal RXLOST and change to RX_NONE
+  if (m_frameCount >= MAX_FRAMES) {
     DEBUG1("DStarRX: data sync timed out, lost lock");
 
     io.setDecode(false);
@@ -437,24 +431,35 @@ void CDStarRX::processData(bool bit)
 
     serial.writeDStarLost();
 
+    m_maxFrameCorr = 0;
+    m_maxDataCorr  = 0;
+
     m_rxState = DSRXS_NONE;
     return;
   }
 
-  // Send a data frame to the host if the required number of bits have been received, or if a data sync has been seen
-  if (m_rxBufferBits == DSTAR_DATA_LENGTH_BITS) {
-    if (syncSeen) {
-      m_rxBuffer[9U]  = DSTAR_DATA_SYNC_BYTES[9U];
-      m_rxBuffer[10U] = DSTAR_DATA_SYNC_BYTES[10U];
-      m_rxBuffer[11U] = DSTAR_DATA_SYNC_BYTES[11U];
-	    writeRSSIData(m_rxBuffer);
-    } else {
-	    serial.writeDStarData(m_rxBuffer, DSTAR_DATA_LENGTH_BYTES);
-	  }
+  // Send a data frame to the host if the required number of bits have been received
+  if (m_dataPtr == m_maxSyncPtr) {
+    uint8_t buffer[DSTAR_DATA_LENGTH_BYTES + 2U];
+    samplesToBits(m_dataBuffer, m_startPtr, DSTAR_DATA_LENGTH_SYMBOLS, buffer, DSTAR_DATA_LENGTH_SAMPLES);
 
-    // Start the next frame
-    ::memset(m_rxBuffer, 0x00U, DSTAR_DATA_LENGTH_BYTES + 2U);
-    m_rxBufferBits = 0U;
+    if ((m_frameCount % 21U) == 0U) {
+      if (m_frameCount == 0U) {
+        buffer[9U]  = DSTAR_DATA_SYNC_BYTES[9U];
+        buffer[10U] = DSTAR_DATA_SYNC_BYTES[10U];
+        buffer[11U] = DSTAR_DATA_SYNC_BYTES[11U];
+        DEBUG5("DStarRX: found start/sync/max/min", m_startPtr, m_syncPtr, m_maxSyncPtr, m_minSyncPtr);
+      }
+
+      writeRSSIData(buffer);
+    } else {
+      serial.writeDStarData(buffer, DSTAR_DATA_LENGTH_BYTES);
+    }
+
+    m_frameCount++;
+
+    m_maxFrameCorr = 0;
+    m_maxDataCorr  = 0;
   }
 }
 
@@ -500,6 +505,105 @@ void CDStarRX::writeRSSIData(unsigned char* data)
   m_rssiCount = 0U;
 }
 
+bool CDStarRX::correlateFrameSync()
+{
+  if (countBits64((m_bitBuffer[m_bitPtr] & DSTAR_FRAME_SYNC_MASK) ^ DSTAR_FRAME_SYNC_DATA) <= FRAME_SYNC_ERRS) {
+    uint16_t ptr = m_dataPtr + DSTAR_DATA_LENGTH_SAMPLES - DSTAR_FRAME_SYNC_LENGTH_SAMPLES + DSTAR_RADIO_SYMBOL_LENGTH;
+    if (ptr >= DSTAR_DATA_LENGTH_SAMPLES)
+      ptr -= DSTAR_DATA_LENGTH_SAMPLES;
+
+    q31_t corr = 0;
+
+    for (uint8_t i = 0U; i < DSTAR_FRAME_SYNC_LENGTH_SYMBOLS; i++) {
+      q15_t val = m_dataBuffer[ptr];
+
+      if (DSTAR_FRAME_SYNC_SYMBOLS[i])
+        corr -= val;
+      else
+        corr += val;
+
+      ptr += DSTAR_RADIO_SYMBOL_LENGTH;
+      if (ptr >= DSTAR_DATA_LENGTH_SAMPLES)
+        ptr -= DSTAR_DATA_LENGTH_SAMPLES;
+    }
+
+    if (corr > m_maxFrameCorr) {
+      m_maxFrameCorr = corr;
+      m_headerPtr    = 0U;
+      return true;
+    }
+  }
+
+  return false;
+}
+
+bool CDStarRX::correlateDataSync()
+{
+  uint8_t maxErrs = 0U;
+  if (m_rxState == DSRXS_DATA)
+    maxErrs = DATA_SYNC_ERRS;
+
+  if (countBits64((m_bitBuffer[m_bitPtr] & DSTAR_DATA_SYNC_MASK) ^ DSTAR_DATA_SYNC_DATA) <= maxErrs) {
+    uint16_t ptr = m_dataPtr + DSTAR_DATA_LENGTH_SAMPLES - DSTAR_DATA_SYNC_LENGTH_SAMPLES + DSTAR_RADIO_SYMBOL_LENGTH;
+    if (ptr >= DSTAR_DATA_LENGTH_SAMPLES)
+      ptr -= DSTAR_DATA_LENGTH_SAMPLES;
+
+    q31_t corr = 0;
+
+    for (uint8_t i = 0U; i < DSTAR_DATA_SYNC_LENGTH_SYMBOLS; i++) {
+      q15_t val = m_dataBuffer[ptr];
+
+      if (DSTAR_DATA_SYNC_SYMBOLS[i])
+        corr -= val;
+      else
+        corr += val;
+
+      ptr += DSTAR_RADIO_SYMBOL_LENGTH;
+      if (ptr >= DSTAR_DATA_LENGTH_SAMPLES)
+        ptr -= DSTAR_DATA_LENGTH_SAMPLES;
+    }
+
+    if (corr > m_maxDataCorr) {
+      m_maxDataCorr = corr;
+      m_frameCount  = 0U;
+
+      m_syncPtr    = m_dataPtr;
+
+      m_startPtr   = m_dataPtr + DSTAR_RADIO_SYMBOL_LENGTH;
+      if (m_startPtr >= DSTAR_DATA_LENGTH_SAMPLES)
+        m_startPtr -= DSTAR_DATA_LENGTH_SAMPLES;
+
+      m_maxSyncPtr = m_syncPtr + 1U;
+      if (m_maxSyncPtr >= DSTAR_DATA_LENGTH_SAMPLES)
+        m_maxSyncPtr -= DSTAR_DATA_LENGTH_SAMPLES;
+
+      m_minSyncPtr = m_syncPtr + DSTAR_DATA_LENGTH_SAMPLES - 1U;
+      if (m_minSyncPtr >= DSTAR_DATA_LENGTH_SAMPLES)
+        m_minSyncPtr -= DSTAR_DATA_LENGTH_SAMPLES;
+
+      return true;
+    }
+  }
+
+  return false;
+}
+
+void CDStarRX::samplesToBits(const q15_t* inBuffer, uint16_t start, uint16_t count, uint8_t* outBuffer, uint16_t limit)
+{
+  for (uint16_t i = 0U; i < count; i++) {
+    q15_t sample = inBuffer[start];
+
+    if (sample < 0)
+      WRITE_BIT2(outBuffer, i, true);
+    else
+      WRITE_BIT2(outBuffer, i, false);
+
+    start += DSTAR_RADIO_SYMBOL_LENGTH;
+    if (start >= limit)
+      start -= limit;
+  }
+}
+
 bool CDStarRX::rxHeader(uint8_t* in, uint8_t* out)
 {
   int i;
@@ -715,3 +819,6 @@ bool CDStarRX::checksum(const uint8_t* header) const
 
   return crc8[0U] == header[DSTAR_HEADER_LENGTH_BYTES - 2U] && crc8[1U] == header[DSTAR_HEADER_LENGTH_BYTES - 1U];
 }
+
+#endif
+

DStarRX.h

@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2015,2016,2017 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2015,2016,2017,2020 by Jonathan Naylor G4KLX
  *
  *   This program is free software; you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
@@ -16,10 +16,13 @@
  *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  */
 
+#include "Config.h"
+
+#if defined(MODE_DSTAR)
+
 #if !defined(DSTARRX_H)
 #define  DSTARRX_H
 
-#include "Config.h"
 #include "DStarDefines.h"
 
 enum DSRX_STATE {
@@ -37,13 +40,21 @@ public:
   void reset();
 
 private:
-  uint32_t     m_pll;
-  bool         m_prev;
   DSRX_STATE   m_rxState;
-  uint32_t     m_patternBuffer;
-  uint8_t      m_rxBuffer[100U];
-  unsigned int m_rxBufferBits;
-  unsigned int m_dataBits;
+  uint64_t     m_bitBuffer[DSTAR_RADIO_SYMBOL_LENGTH];
+  q15_t        m_headerBuffer[DSTAR_FEC_SECTION_LENGTH_SAMPLES + 2U * DSTAR_RADIO_SYMBOL_LENGTH];
+  q15_t        m_dataBuffer[DSTAR_DATA_LENGTH_SAMPLES];
+  uint16_t     m_bitPtr;
+  uint16_t     m_headerPtr;
+  uint16_t     m_dataPtr;
+  uint16_t     m_startPtr;
+  uint16_t     m_syncPtr;
+  uint16_t     m_minSyncPtr;
+  uint16_t     m_maxSyncPtr;
+  q31_t        m_maxFrameCorr;
+  q31_t        m_maxDataCorr;
+  uint16_t     m_frameCount;
+  uint8_t      m_countdown;
   unsigned int m_mar;
   int          m_pathMetric[4U];
   unsigned int m_pathMemory0[42U];
@@ -54,9 +65,12 @@ private:
   uint32_t     m_rssiAccum;
   uint16_t     m_rssiCount;
   
-  void    processNone(bool bit);
-  void    processHeader(bool bit);
-  void    processData(bool bit);
+  void    processNone(q15_t sample);
+  void    processHeader(q15_t sample);
+  void    processData();
+  bool    correlateFrameSync();
+  bool    correlateDataSync();
+  void    samplesToBits(const q15_t* inBuffer, uint16_t start, uint16_t count, uint8_t* outBuffer, uint16_t limit);
   void    writeRSSIHeader(unsigned char* header);
   void    writeRSSIData(unsigned char* data);
   bool    rxHeader(uint8_t* in, uint8_t* out);
@@ -68,3 +82,5 @@ private:
 
 #endif
 
+#endif
+

DStarTX.cpp

@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2009-2017 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2009-2017,2020 by Jonathan Naylor G4KLX
  *   Copyright (C) 2017 by Andy Uribe CA6JAU
  *
  *   This program is free software; you can redistribute it and/or modify
@@ -18,6 +18,9 @@
  */
 
 #include "Config.h"
+
+#if defined(MODE_DSTAR)
+
 #include "Globals.h"
 #include "DStarTX.h"
 
@@ -198,7 +201,7 @@ m_txDelay(60U)       // 100ms
 {
   ::memset(m_modState, 0x00U, 20U * sizeof(q15_t));
 
-  m_modFilter.L           = DSTAR_RADIO_BIT_LENGTH;
+  m_modFilter.L           = DSTAR_RADIO_SYMBOL_LENGTH;
   m_modFilter.phaseLength = GAUSSIAN_0_35_FILTER_PHASE_LEN;
   m_modFilter.pCoeffs     = GAUSSIAN_0_35_FILTER;
   m_modFilter.pState      = m_modState;
@@ -217,11 +220,12 @@ void CDStarTX::process()
         m_poBuffer[m_poLen++] = BIT_SYNC;
     } else {
       // Pop the type byte off
-      m_buffer.get();
+      uint8_t dummy;
+      m_buffer.get(dummy);
 
       uint8_t header[DSTAR_HEADER_LENGTH_BYTES];
       for (uint8_t i = 0U; i < DSTAR_HEADER_LENGTH_BYTES; i++)
-        header[i] = m_buffer.get();
+        m_buffer.get(header[i]);
 
       uint8_t buffer[86U];
       txHeader(header, buffer + 2U);
@@ -239,21 +243,23 @@ void CDStarTX::process()
  
   if (type == DSTAR_DATA && m_poLen == 0U) {
     // Pop the type byte off
-    m_buffer.get();
+    uint8_t dummy;
+    m_buffer.get(dummy);
 
     for (uint8_t i = 0U; i < DSTAR_DATA_LENGTH_BYTES; i++)
-      m_poBuffer[m_poLen++] = m_buffer.get();
+      m_buffer.get(m_poBuffer[m_poLen++]);
 
     m_poPtr = 0U;
   }
 
   if (type == DSTAR_EOT && m_poLen == 0U) {
     // Pop the type byte off
-    m_buffer.get();
+    uint8_t dummy;
+    m_buffer.get(dummy);
 
     for (uint8_t j = 0U; j < 3U; j++) {
-      for (uint8_t i = 0U; i < DSTAR_EOT_LENGTH_BYTES; i++)
-        m_poBuffer[m_poLen++] = DSTAR_EOT_BYTES[i];
+      for (uint8_t i = 0U; i < DSTAR_END_SYNC_LENGTH_BYTES; i++)
+        m_poBuffer[m_poLen++] = DSTAR_END_SYNC_BYTES[i];
     }
      
     m_poPtr = 0U;
@@ -262,11 +268,11 @@ void CDStarTX::process()
   if (m_poLen > 0U) {
     uint16_t space = io.getSpace();
     
-    while (space > (8U * DSTAR_RADIO_BIT_LENGTH)) {
+    while (space > (8U * DSTAR_RADIO_SYMBOL_LENGTH)) {
       uint8_t c = m_poBuffer[m_poPtr++];
       writeByte(c);
 
-      space -= 8U * DSTAR_RADIO_BIT_LENGTH;
+      space -= 8U * DSTAR_RADIO_SYMBOL_LENGTH;
       
       if (m_poPtr >= m_poLen) {
         m_poPtr = 0U;
@@ -277,7 +283,7 @@ void CDStarTX::process()
   }
 }
 
-uint8_t CDStarTX::writeHeader(const uint8_t* header, uint8_t length)
+uint8_t CDStarTX::writeHeader(const uint8_t* header, uint16_t length)
 {
   if (length != DSTAR_HEADER_LENGTH_BYTES)
     return 4U;
@@ -296,7 +302,7 @@ uint8_t CDStarTX::writeHeader(const uint8_t* header, uint8_t length)
   return 0U;
 }
 
-uint8_t CDStarTX::writeData(const uint8_t* data, uint8_t length)
+uint8_t CDStarTX::writeData(const uint8_t* data, uint16_t length)
 {
   if (length != DSTAR_DATA_LENGTH_BYTES)
     return 4U;
@@ -412,7 +418,7 @@ void CDStarTX::txHeader(const uint8_t* in, uint8_t* out) const
 void CDStarTX::writeByte(uint8_t c)
 {
   q15_t inBuffer[8U];
-  q15_t outBuffer[DSTAR_RADIO_BIT_LENGTH * 8U];
+  q15_t outBuffer[DSTAR_RADIO_SYMBOL_LENGTH * 8U];
 
   uint8_t mask = 0x01U;
 
@@ -427,7 +433,7 @@ void CDStarTX::writeByte(uint8_t c)
 
   ::arm_fir_interpolate_q15(&m_modFilter, inBuffer, outBuffer, 8U);
   
-  io.write(STATE_DSTAR, outBuffer, DSTAR_RADIO_BIT_LENGTH * 8U);
+  io.write(STATE_DSTAR, outBuffer, DSTAR_RADIO_SYMBOL_LENGTH * 8U);
 }
 
 void CDStarTX::setTXDelay(uint8_t delay)
@@ -443,3 +449,5 @@ uint8_t CDStarTX::getSpace() const
   return m_buffer.getSpace() / (DSTAR_DATA_LENGTH_BYTES + 1U);
 }
 
+#endif
+

DStarTX.h

@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2015,2016,2017 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2015,2016,2017,2020 by Jonathan Naylor G4KLX
  *
  *   This program is free software; you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
@@ -16,19 +16,21 @@
  *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  */
 
+#include "Config.h"
+
+#if defined(MODE_DSTAR)
+
 #if !defined(DSTARTX_H)
 #define  DSTARTX_H
 
-#include "Config.h"
-
-#include "SerialRB.h"
+#include "RingBuffer.h"
 
 class CDStarTX {
 public:
   CDStarTX();
 
-  uint8_t writeHeader(const uint8_t* header, uint8_t length);
-  uint8_t writeData(const uint8_t* data, uint8_t length);
+  uint8_t writeHeader(const uint8_t* header, uint16_t length);
+  uint8_t writeData(const uint8_t* data, uint16_t length);
   uint8_t writeEOT();
 
   void process();
@@ -38,7 +40,7 @@ public:
   uint8_t getSpace() const;
 
 private:
-  CSerialRB                        m_buffer;
+  CRingBuffer<uint8_t>             m_buffer;
   arm_fir_interpolate_instance_q15 m_modFilter;
   q15_t                            m_modState[20U];    // blockSize + phaseLength - 1, 8 + 9 - 1 plus some spare
   uint8_t                          m_poBuffer[600U];
@@ -52,3 +54,5 @@ private:
 
 #endif
 
+#endif
+

Debug.h

@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2015,2016,2017 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2015,2016,2017,2021 by Jonathan Naylor G4KLX
  *
  *   This program is free software; you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
@@ -27,6 +27,7 @@
 #define  DEBUG3(a,b,c)      serial.writeDebug((a),(b),(c))
 #define  DEBUG4(a,b,c,d)    serial.writeDebug((a),(b),(c),(d))
 #define  DEBUG5(a,b,c,d,e)  serial.writeDebug((a),(b),(c),(d),(e))
+#define  DEBUG_DUMP(a,b)    serial.writeDebugDump((a),(b))
 
 #endif
 

FM.h

@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2020 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2020,2021 by Jonathan Naylor G4KLX
  *
  *   This program is free software; you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
@@ -16,33 +16,41 @@
  *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  */
 
+#include "Config.h"
+
+#if defined(MODE_FM)
+
 #if !defined(FM_H)
 #define  FM_H
 
-#include "Config.h"
-
 #include "FMBlanking.h"
 #include "FMCTCSSRX.h"
 #include "FMCTCSSTX.h"
 #include "FMTimeout.h"
 #include "FMKeyer.h"
 #include "FMTimer.h"
+#include "RingBuffer.h"
 #include "FMDirectForm1.h"
-#include "FMDownsampler.h"
+#include "FMDownSampler.h"
+#include "FMUpSampler.h"
+#include "FMNoiseSquelch.h"
 
 enum FM_STATE {
   FS_LISTENING,
-  FS_KERCHUNK,
-  FS_RELAYING,
-  FS_RELAYING_WAIT,
-  FS_TIMEOUT,
-  FS_TIMEOUT_WAIT,
+  FS_KERCHUNK_RF,
+  FS_RELAYING_RF,
+  FS_RELAYING_WAIT_RF,
+  FS_TIMEOUT_RF,
+  FS_TIMEOUT_WAIT_RF,
+  FS_KERCHUNK_EXT,
+  FS_RELAYING_EXT,
+  FS_RELAYING_WAIT_EXT,
+  FS_TIMEOUT_EXT,
+  FS_TIMEOUT_WAIT_EXT,
   FS_HANG
 };
 
 
-
-
 class CFM {
 public:
   CFM();
@@ -55,13 +63,20 @@ public:
 
   uint8_t setCallsign(const char* callsign, uint8_t speed, uint16_t frequency, uint8_t time, uint8_t holdoff, uint8_t highLevel, uint8_t lowLevel, bool callsignAtStart, bool callsignAtEnd, bool callsignAtLatch);
   uint8_t setAck(const char* rfAck, uint8_t speed, uint16_t frequency, uint8_t minTime, uint16_t delay, uint8_t level);
-  uint8_t setMisc(uint16_t timeout, uint8_t timeoutLevel, uint8_t ctcssFrequency, uint8_t ctcssThreshold, uint8_t ctcssLevel, uint8_t kerchunkTime, uint8_t hangTime, bool useCOS, bool cosInvert, uint8_t rfAudioBoost, uint8_t maxDev, uint8_t rxLevel);
+  uint8_t setMisc(uint16_t timeout, uint8_t timeoutLevel, uint8_t ctcssFrequency, uint8_t ctcssHighThreshold, uint8_t ctcssLowThreshold, uint8_t ctcssLevel, uint8_t kerchunkTime, uint8_t hangTime, uint8_t accessMode, bool linkMode, bool cosInvert, bool noiseSquelch, uint8_t squelchHighThreshold, uint8_t squelchLowThreshold, uint8_t rfAudioBoost, uint8_t maxDev, uint8_t rxLevel);
+  uint8_t setExt(const char* ack, uint8_t audioBoost, uint8_t speed, uint16_t frequency, uint8_t level);
+
+  uint8_t getSpace() const;
+
+  uint8_t writeData(const uint8_t* data, uint8_t length);
 
 private:
   CFMKeyer             m_callsign;
   CFMKeyer             m_rfAck;
+  CFMKeyer             m_extAck;
   CFMCTCSSRX           m_ctcssRX;
   CFMCTCSSTX           m_ctcssTX;
+  CFMNoiseSquelch      m_squelch;
   CFMTimeout           m_timeoutTone;
   FM_STATE             m_state;
   bool                 m_callsignAtStart;
@@ -74,30 +89,70 @@ private:
   CFMTimer             m_ackMinTimer;
   CFMTimer             m_ackDelayTimer;
   CFMTimer             m_hangTimer;
+  CFMTimer             m_statusTimer;
+  CFMTimer             m_reverseTimer;
+  bool                 m_needReverse;
   CFMDirectFormI       m_filterStage1;
   CFMDirectFormI       m_filterStage2;
   CFMDirectFormI       m_filterStage3;
-  CFMDirectFormI       m_preemphasis;
-  CFMDirectFormI       m_deemphasis;
   CFMBlanking          m_blanking;
-  bool                 m_useCOS;
+  uint8_t              m_accessMode;
+  bool                 m_linkMode;
   bool                 m_cosInvert;
+  bool                 m_noiseSquelch;
   q15_t                m_rfAudioBoost;
-  CFMDownsampler       m_downsampler;
+  q15_t                m_extAudioBoost;
+  CFMDownSampler       m_downSampler;
+  bool                 m_extEnabled;
+  q15_t                m_rxLevel;
+  CRingBuffer<q15_t>   m_inputRFRB;
+  CRingBuffer<q15_t>   m_outputRFRB;
+  CFMUpSampler         m_inputExtRB;
+  bool                 m_rfSignal;
+  bool                 m_extSignal;
 
-  void stateMachine(bool validSignal);
-  void listeningState(bool validSignal);
-  void kerchunkState(bool validSignal);
-  void relayingState(bool validSignal);
-  void relayingWaitState(bool validSignal);
-  void timeoutState(bool validSignal);
-  void timeoutWaitState(bool validSignal);
-  void hangState(bool validSignal);
+  void stateMachine(bool validRFSignal, bool validExtSignal);
+
+  void repeaterSamples(bool cos, q15_t* samples, uint8_t length);
+  void linkSamples(bool cos, q15_t* samples, uint8_t length);
+
+  void duplexStateMachine(bool validRFSignal, bool validExtSignal);
+  void listeningStateDuplex(bool validRFSignal, bool validExtSignal);
+  void kerchunkRFStateDuplex(bool validSignal);
+  void relayingRFStateDuplex(bool validSignal);
+  void relayingRFWaitStateDuplex(bool validSignal);
+  void timeoutRFStateDuplex(bool validSignal);
+  void timeoutRFWaitStateDuplex(bool validSignal);
+  void kerchunkExtStateDuplex(bool validSignal);
+  void relayingExtStateDuplex(bool validSignal);
+  void relayingExtWaitStateDuplex(bool validSignal);
+  void timeoutExtStateDuplex(bool validSignal);
+  void timeoutExtWaitStateDuplex(bool validSignal);
+  void hangStateDuplex(bool validRFSignal, bool validExtSignal);
+
+  void simplexStateMachine(bool validRFSignal, bool validExtSignal);
+  void listeningStateSimplex(bool validRFSignal, bool validExtSignal);
+  void relayingRFStateSimplex(bool validSignal);
+  void relayingRFWaitStateSimplex(bool validSignal);
+  void timeoutRFStateSimplex(bool validSignal);
+  void timeoutRFWaitStateSimplex(bool validSignal);
+  void relayingExtStateSimplex(bool validSignal);
+  void relayingExtWaitStateSimplex(bool validSignal);
+  void timeoutExtStateSimplex(bool validSignal);
+  void timeoutExtWaitStateSimplex(bool validSignal);
+
+  void linkStateMachine(bool validRFSignal, bool validExtSignal);
 
   void clock(uint8_t length);
 
   void sendCallsign();
   void beginRelaying();
+
+  void insertDelay(uint16_t ms);
+  void insertSilence(uint16_t ms);
 };
 
 #endif
+
+#endif
+

FMBlanking.cpp

@@ -17,6 +17,9 @@
  */
 
 #include "Config.h"
+
+#if defined(MODE_FM)
+
 #include "Globals.h"
 #include "FMBlanking.h"
 
@@ -80,3 +83,6 @@ q15_t CFMBlanking::process(q15_t sample)
 
   return sample;
 }
+
+#endif
+

FMBlanking.h

@@ -16,11 +16,13 @@
  *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  */
 
+#include "Config.h"
+
+#if defined(MODE_FM)
+
 #if !defined(FMBlanking_H)
 #define  FMBlanking_H
 
-#include "Config.h"
-
 class CFMBlanking {
 public:
   CFMBlanking();
@@ -39,3 +41,6 @@ private:
 };
 
 #endif
+
+#endif
+

FMCTCSSRX.cpp

@@ -17,6 +17,9 @@
  */
 
 #include "Config.h"
+
+#if defined(MODE_FM)
+
 #include "Globals.h"
 #include "FMCTCSSRX.h"
 
@@ -82,19 +85,17 @@ const uint16_t N = 24000U / 4U;
 
 CFMCTCSSRX::CFMCTCSSRX() :
 m_coeffDivTwo(0),
-m_threshold(0),
+m_highThreshold(0),
+m_lowThreshold(0),
 m_count(0U),
 m_q0(0),
 m_q1(0),
-m_result(CTS_NONE),
-m_rxLevelInverse(1)
+m_state(false)
 {
 }
 
-uint8_t CFMCTCSSRX::setParams(uint8_t frequency, uint8_t threshold, uint8_t level)
+uint8_t CFMCTCSSRX::setParams(uint8_t frequency, uint8_t highThreshold, uint8_t lowThreshold)
 {
-  m_rxLevelInverse = q15Division(65535, q15_t(level * 128));
-
   m_coeffDivTwo = 0;
 
   for (uint8_t i = 0U; i < CTCSS_TABLE_DATA_LEN; i++) {
@@ -107,16 +108,16 @@ uint8_t CFMCTCSSRX::setParams(uint8_t frequency, uint8_t threshold, uint8_t leve
   if (m_coeffDivTwo == 0)
     return 4U;
 
-  m_threshold = q31_t(threshold);
+  m_highThreshold = q31_t(highThreshold);
+  m_lowThreshold  = q31_t(lowThreshold);
 
   return 0U;
 }
 
-uint8_t CFMCTCSSRX::process(q15_t sample)
+bool CFMCTCSSRX::process(q15_t sample)
 {
-  q31_t sample31 = q31_t(sample) * m_rxLevelInverse;
-
-  m_result &= ~CTS_READY;
+  //get more dynamic into the decoder by multiplying the sample by 1.5
+  q31_t sample31 = q31_t(sample) +  (q31_t(sample) >> 1);
 
   q31_t q2 = m_q1;
   m_q1 = m_q0;
@@ -149,41 +150,32 @@ uint8_t CFMCTCSSRX::process(q15_t sample)
     // value = m_q0 * m_q0 + m_q1 * m_q1 - m_q0 * m_q1 * m_coeffDivTwo * 2
     q31_t value = t2 + t4 - t9;
 
-    bool previousCTCSSValid = CTCSS_VALID(m_result);
-    m_result |= CTS_READY;
-    if (value >= m_threshold)
-      m_result |= CTS_VALID;
-    else
-      m_result &= ~CTS_VALID;
+    bool previousState = m_state;
 
-    if (previousCTCSSValid != CTCSS_VALID(m_result))
-      DEBUG4("CTCSS Value / Threshold / Valid", value, m_threshold, CTCSS_VALID(m_result));
+    q31_t threshold = m_highThreshold;
+    if (previousState)
+      threshold = m_lowThreshold;
+
+    m_state = value >= threshold;
+
+    if (previousState != m_state)
+      DEBUG4("CTCSS Value / Threshold / Valid", value, threshold, m_state);
 
     m_count = 0U;
     m_q0 = 0;
     m_q1 = 0;
   }
 
-  return m_result;
+  return m_state;
 }
 
 void CFMCTCSSRX::reset()
 {
   m_q0 = 0;
   m_q1 = 0;
-  m_result = CTS_NONE;
-  m_count  = 0U;
+  m_state = false;
+  m_count = 0U;
 }
 
-//Taken from https://en.wikipedia.org/wiki/Q_(number_format)#Division
-q15_t CFMCTCSSRX::q15Division(q15_t a, q15_t divisor)
-{
-  q31_t a31 = q31_t(a) << 16;
+#endif
 
-  if (((a >> 31) & 1) == ((divisor >> 15) & 1))
-    a31 += divisor >> 1;
-  else
-    a31 -= divisor >> 1;
-
-  return a31 / divisor;
-}

FMCTCSSRX.h

@@ -16,40 +16,34 @@
  *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  */
 
-#if !defined(FMCTCSSRX_H)
-#define  FMCTCSSRX_H
-
 #include "Config.h"
 
-const uint8_t CTS_NONE  = 0U;
-const uint8_t CTS_READY = 1U;
-const uint8_t CTS_VALID = 2U;
+#if defined(MODE_FM)
 
-#define CTCSS_READY(a) ((a & CTS_READY) != 0)
-#define CTCSS_NOT_READY(a) ((a & CTS_READY) == 0)
-#define CTCSS_VALID(a) ((a & CTS_VALID) != 0)
-#define CTCSS_NOT_VALID(a) ((a & CTS_VALID) == 0)
+#if !defined(FMCTCSSRX_H)
+#define  FMCTCSSRX_H
 
 class CFMCTCSSRX {
 public:
   CFMCTCSSRX();
 
-  uint8_t setParams(uint8_t frequency, uint8_t threshold, uint8_t level);
+  uint8_t setParams(uint8_t frequency, uint8_t highThreshold, uint8_t lowThreshold);
   
-  uint8_t process(q15_t sample);
+  bool process(q15_t sample);
 
   void reset();
 
 private:
   q63_t    m_coeffDivTwo;
-  q31_t    m_threshold;
+  q31_t    m_highThreshold;
+  q31_t    m_lowThreshold;
   uint16_t m_count;
   q31_t    m_q0;
   q31_t    m_q1;
-  uint8_t  m_result;
-  q15_t    m_rxLevelInverse;
-
-  q15_t q15Division(q15_t a, q15_t divisor);
+  bool     m_state;
 };
 
 #endif
+
+#endif
+

FMCTCSSTX.cpp

@@ -17,6 +17,9 @@
  */
 
 #include "Config.h"
+
+#if defined(MODE_FM)
+
 #include "Globals.h"
 #include "FMCTCSSTX.h"
 
@@ -115,11 +118,17 @@ uint8_t CFMCTCSSTX::setParams(uint8_t frequency, uint8_t level)
   return 0U;
 }
 
-q15_t CFMCTCSSTX::getAudio()
+q15_t CFMCTCSSTX::getAudio(bool reverse)
 {
   q15_t sample = m_values[m_n++];
-  if(m_n >= m_length)
+  if (m_n >= m_length)
     m_n = 0U;
   
-  return sample;
+  if (reverse)
+    return -sample;
+  else
+    return sample;
 }
+
+#endif
+

FMCTCSSTX.h

@@ -16,18 +16,20 @@
  *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  */
 
+#include "Config.h"
+
+#if defined(MODE_FM)
+
 #if !defined(FMCTCSSTX_H)
 #define  FMCTCSSTX_H
 
-#include "Config.h"
-
 class CFMCTCSSTX {
 public:
   CFMCTCSSTX();
 
   uint8_t setParams(uint8_t frequency, uint8_t level);
 
-  q15_t getAudio();
+  q15_t getAudio(bool reverse);
 
 private:
   q15_t*   m_values;
@@ -36,3 +38,6 @@ private:
 };
 
 #endif
+
+#endif
+

FMDirectForm1.h

@@ -29,7 +29,11 @@ THE SOFTWARE.
 
 // based on https://raw.githubusercontent.com/berndporr/iir_fixed_point/master/DirectFormI.h
 
-#include "Globals.h"
+#include "Config.h"
+
+#if defined(MODE_FM)
+
+#include <cstdint>
 
 #ifndef DIRECTFORMI_H_
 #define DIRECTFORMI_H_
@@ -108,4 +112,7 @@ private:
 	q31_t c_a1,c_a2; // IIR
 };
 
-#endif /* DIRECTFORMI_H */
+#endif /* DIRECTFORMI_H */
+
+#endif
+

FMDownSampler.cpp

@@ -0,0 +1,80 @@
+/*
+ *   Copyright (C) 2020 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2020 by Geoffrey Merck F4FXL - KC3FRA
+ *
+ *   This program is free software; you can redistribute it and/or modify
+ *   it under the terms of the GNU General Public License as published by
+ *   the Free Software Foundation; either version 2 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ *
+ *   You should have received a copy of the GNU General Public License
+ *   along with this program; if not, write to the Free Software
+ *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include "Config.h"
+
+#if defined(MODE_FM)
+
+#include "FMDownSampler.h"
+
+CFMDownSampler::CFMDownSampler(uint16_t length) :
+m_ringBuffer(length),
+m_samplePack(0U),
+m_samplePackPointer(NULL),
+m_sampleIndex(0U)
+{
+  m_samplePackPointer = (uint8_t*)&m_samplePack;
+}
+
+void CFMDownSampler::addSample(q15_t sample)
+{
+  uint32_t usample = uint32_t(int32_t(sample) + 2048);
+  //only take one of three samples
+  switch(m_sampleIndex){
+    case 0:
+      m_samplePack = usample << 12;
+    break;
+    case 3:{
+      m_samplePack |= usample;
+      
+      //we did not use MSB; skip it
+      TSamplePairPack pair{m_samplePackPointer[0U], m_samplePackPointer[1U], m_samplePackPointer[2U]}; 
+
+      m_ringBuffer.put(pair);
+
+      m_samplePack = 0U;//reset the sample pack
+    }
+    break;
+    default:
+        //Just skip this sample
+    break;
+  }
+
+  m_sampleIndex++;
+  if (m_sampleIndex >= 6U)//did we pack two samples ?
+      m_sampleIndex = 0U;  
+}
+
+bool CFMDownSampler::getPackedData(TSamplePairPack& data)
+{
+  return m_ringBuffer.get(data);
+}
+
+uint16_t CFMDownSampler::getData()
+{
+  return m_ringBuffer.getData();
+}
+
+void CFMDownSampler::reset()
+{
+  m_sampleIndex = 0U;
+}
+
+#endif
+

FMDownSampler.h

@@ -17,27 +17,36 @@
  *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  */
 
+#include "Config.h"
+
+#if defined(MODE_FM)
+
 #if !defined(FMDOWNSAMPLER_H)
 #define FMDOWNSAMPLER_H
 
-#include "Config.h"
-#include "FMDownsampleRB.h"
+#include "RingBuffer.h"
+#include "FMSamplePairPack.h"
 
-class CFMDownsampler {
+class CFMDownSampler {
 public:
-  CFMDownsampler(uint16_t length);
+  CFMDownSampler(uint16_t length);
+
   void addSample(q15_t sample);
-  inline bool getPackedData(uint8_t& data){ return m_ringBuffer.get(data); };
-  inline bool hasOverflowed() { return m_ringBuffer.hasOverflowed(); };
+
+  bool getPackedData(TSamplePairPack& data);
+
+  uint16_t getData();
+
+  void reset();
 
 private:
-  CFMDownsampleRB m_ringBuffer;
-  union {
-    int32_t m_samplePack;
-    int8_t  m_samplePackBytes[4];
-  };
-  uint8_t m_packIndex;
-  uint8_t m_downSampleIndex;
+  CRingBuffer<TSamplePairPack> m_ringBuffer;
+  uint32_t                     m_samplePack;
+  uint8_t*                     m_samplePackPointer;
+  uint8_t                      m_sampleIndex;
 };
 
-#endif
+#endif
+
+#endif
+

FMDownsampler.cpp

@@ -1,63 +0,0 @@
-/*
- *   Copyright (C) 2020 by Jonathan Naylor G4KLX
- *   Copyright (C) 2020 by Geoffrey Merck F4FXL - KC3FRA
- *
- *   This program is free software; you can redistribute it and/or modify
- *   it under the terms of the GNU General Public License as published by
- *   the Free Software Foundation; either version 2 of the License, or
- *   (at your option) any later version.
- *
- *   This program is distributed in the hope that it will be useful,
- *   but WITHOUT ANY WARRANTY; without even the implied warranty of
- *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- *   GNU General Public License for more details.
- *
- *   You should have received a copy of the GNU General Public License
- *   along with this program; if not, write to the Free Software
- *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
- */
-
-#include "Config.h"
-#include "FMDownsampler.h"
-
-
-CFMDownsampler::CFMDownsampler(uint16_t length) :
-m_ringBuffer(length),//length might need tweaking
-m_packIndex(0),
-m_downSampleIndex(0)
-{
-    m_samplePack = 0;
-}
-
-void CFMDownsampler::addSample(q15_t sample)
-{
-    //only take one of three samples
-    if(m_downSampleIndex == 0) {
-      switch(m_packIndex){
-        case 0:
-          m_samplePack = int32_t(sample) << 12;
-        break;
-        case 1:{
-            m_samplePack |= int32_t(sample);
-            
-            //we did not use MSB; skip it
-            m_ringBuffer.put(m_samplePackBytes[1]); 
-            m_ringBuffer.put(m_samplePackBytes[2]); 
-            m_ringBuffer.put(m_samplePackBytes[3]); 
-
-            m_samplePack = 0;
-        }
-        break;
-        default:
-            //should never happen
-        break;
-        }
-        m_packIndex++;
-        if(m_packIndex >= 2)
-            m_packIndex = 0;  
-    }
-
-    m_downSampleIndex++;
-    if(m_downSampleIndex >= 3)
-        m_downSampleIndex = 0;
-}

FMKeyer.cpp

@@ -17,6 +17,9 @@
  */
 
 #include "Config.h"
+
+#if defined(MODE_FM)
+
 #include "Globals.h"
 #include "FMKeyer.h"
 
@@ -205,7 +208,15 @@ void CFMKeyer::stop()
   m_audioPos = 0U;
 }
 
+bool CFMKeyer::isWanted() const
+{
+  return m_wanted;
+}
+
 bool CFMKeyer::isRunning() const
 {
   return m_poPos > 0U || m_dotPos > 0U || m_audioPos > 0U;
 }
+
+#endif
+

FMKeyer.h

@@ -16,11 +16,13 @@
  *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  */
 
+#include "Config.h"
+
+#if defined(MODE_FM)
+
 #if !defined(FMKeyer_H)
 #define  FMKeyer_H
 
-#include "Config.h"
-
 class CFMKeyer {
 public:
   CFMKeyer();
@@ -35,6 +37,8 @@ public:
 
   bool isRunning() const;
 
+  bool isWanted() const;
+
 private:
   bool     m_wanted;
   uint8_t  m_poBuffer[1000U];
@@ -50,3 +54,6 @@ private:
 };
 
 #endif
+
+#endif
+

FMNoiseSquelch.cpp

@@ -0,0 +1,133 @@
+/*
+ *   Copyright (C) 2020 by Jonathan Naylor G4KLX
+ *
+ *   This program is free software; you can redistribute it and/or modify
+ *   it under the terms of the GNU General Public License as published by
+ *   the Free Software Foundation; either version 2 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ *
+ *   You should have received a copy of the GNU General Public License
+ *   along with this program; if not, write to the Free Software
+ *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include "Config.h"
+
+#if defined(MODE_FM)
+
+#include "Globals.h"
+#include "FMNoiseSquelch.h"
+
+// 4500Hz centre frequency
+const q31_t COEFF_DIV_TWO = 821806413;
+
+// 400Hz bandwidth
+const uint16_t N = 24000U / 400U;
+
+CFMNoiseSquelch::CFMNoiseSquelch() :
+m_highThreshold(0),
+m_lowThreshold(0),
+m_count(0U),
+m_q0(0),
+m_q1(0),
+m_state(false),
+m_validCount(0U)
+{
+
+}
+
+void CFMNoiseSquelch::setParams(uint8_t highThreshold, uint8_t lowThreshold)
+{
+  m_highThreshold = q31_t(highThreshold);
+  m_lowThreshold  = q31_t(lowThreshold);
+}
+
+bool CFMNoiseSquelch::process(q15_t sample)
+{
+  //get more dynamic into the decoder by multiplying the sample by 64
+  q31_t sample31 = q31_t(sample) << 6; //+  (q31_t(sample) >> 1);
+
+  q31_t q2 = m_q1;
+  m_q1 = m_q0;
+
+  // Q31 multiplication, t3 = m_coeffDivTwo * 2 * m_q1
+  q63_t t1 = COEFF_DIV_TWO * m_q1;
+  q31_t t2 = __SSAT((t1 >> 31), 31);
+  q31_t t3 = t2 * 2;
+
+  // m_q0 = m_coeffDivTwo * m_q1 * 2 - q2 + sample
+  m_q0 = t3 - q2 + sample31;
+
+  m_count++;
+  if (m_count == N) {
+    // Q31 multiplication, t2 = m_q0 * m_q0
+    q63_t t1 = q63_t(m_q0) * q63_t(m_q0);
+    q31_t t2 = __SSAT((t1 >> 31), 31);
+
+    // Q31 multiplication, t4 = m_q0 * m_q0
+    q63_t t3 = q63_t(m_q1) * q63_t(m_q1);
+    q31_t t4 = __SSAT((t3 >> 31), 31);
+
+    // Q31 multiplication, t9 = m_q0 * m_q1 * m_coeffDivTwo * 2
+    q63_t t5 = q63_t(m_q0) * q63_t(m_q1);
+    q31_t t6 = __SSAT((t5 >> 31), 31);
+    q63_t t7 = t6 * COEFF_DIV_TWO;
+    q31_t t8 = __SSAT((t7 >> 31), 31);
+    q31_t t9  = t8 * 2;
+
+    // value = m_q0 * m_q0 + m_q1 * m_q1 - m_q0 * m_q1 * m_coeffDivTwo * 2
+    q31_t value = t2 + t4 - t9;
+
+    bool previousState = m_state;
+
+    q31_t threshold = m_highThreshold;
+    if (previousState)
+      threshold = m_lowThreshold;
+
+    if (!m_state) {
+      if (value < threshold)
+        m_validCount++;
+      else
+        m_validCount = 0U;
+    }
+
+    if (m_state) {
+      if (value >= threshold)
+        m_invalidCount++;
+      else
+        m_invalidCount = 0U;
+    }
+
+    m_state = m_validCount >= 10U && m_invalidCount < 10U;
+
+    if(previousState && !m_state)
+      m_invalidCount = 0U;
+
+    if (previousState != m_state) {
+      DEBUG4("Noise Squelch Value / Threshold / Valid", value, threshold, m_state);
+      DEBUG3("Valid Count / Invalid Count", m_validCount, m_invalidCount);
+    }
+
+    m_count = 0U;
+    m_q0 = 0;
+    m_q1 = 0;
+  }
+
+  return m_state;
+}
+
+void CFMNoiseSquelch::reset()
+{
+  m_q0 = 0;
+  m_q1 = 0;
+  m_state = false;
+  m_count = 0U;
+}
+
+#endif
+

FMNoiseSquelch.h

@@ -0,0 +1,50 @@
+/*
+ *   Copyright (C) 2020 by Jonathan Naylor G4KLX
+ *
+ *   This program is free software; you can redistribute it and/or modify
+ *   it under the terms of the GNU General Public License as published by
+ *   the Free Software Foundation; either version 2 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ *
+ *   You should have received a copy of the GNU General Public License
+ *   along with this program; if not, write to the Free Software
+ *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include "Config.h"
+
+#if defined(MODE_FM)
+
+#if !defined(FMNOISESQUELCH_H)
+#define  FMNOISESQUELCH_H
+
+class CFMNoiseSquelch {
+public:
+  CFMNoiseSquelch();
+
+  void setParams(uint8_t highThreshold, uint8_t lowThreshold);
+  
+  bool process(q15_t sample);
+
+  void reset();
+
+private:
+  q31_t    m_highThreshold;
+  q31_t    m_lowThreshold;
+  uint16_t m_count;
+  q31_t    m_q0;
+  q31_t    m_q1;
+  bool     m_state;
+  uint8_t  m_validCount;
+  uint8_t  m_invalidCount;
+};
+
+#endif
+
+#endif
+

FMSamplePairPack.h

@@ -0,0 +1,36 @@
+/*
+ *   Copyright (C) 2020 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2020 by Geoffrey Merck F4FXL - KC3FRA
+ *
+ *   This program is free software; you can redistribute it and/or modify
+ *   it under the terms of the GNU General Public License as published by
+ *   the Free Software Foundation; either version 2 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ *
+ *   You should have received a copy of the GNU General Public License
+ *   along with this program; if not, write to the Free Software
+ *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include "Config.h"
+
+#if defined(MODE_FM)
+
+#if !defined(TSAMPLEPACK_H)
+#define TSAMPLEPACK_H
+
+struct TSamplePairPack {
+  uint8_t byte0;
+  uint8_t byte1;
+  uint8_t byte2;
+};
+
+#endif
+
+#endif
+

FMTimeout.cpp

@@ -17,6 +17,9 @@
  */
 
 #include "Config.h"
+
+#if defined(MODE_FM)
+
 #include "Globals.h"
 #include "FMTimeout.h"
 
@@ -36,24 +39,22 @@ m_n(0U)
 
 void CFMTimeout::setParams(uint8_t level)
 {
-  m_level = q15_t(level * 128);
+  m_level = q15_t(level * 5);
 }
 
 q15_t CFMTimeout::getAudio()
 {
-  q15_t sample = 0U;
+  q15_t sample = 0;
   if (!m_running)
     return sample;
 
-  if (m_pos > 12000U) {
-    q31_t sample = BUSY_AUDIO[m_n] * m_level;
-    sample = q15_t(__SSAT((sample >> 15), 16));
+  if (m_pos >= 12000U) {
+    q31_t sample31 = BUSY_AUDIO[m_n] * m_level;
+    sample = q15_t(__SSAT((sample31 >> 15), 16));
 
     m_n++;
     if (m_n >= BUSY_AUDIO_LEN)
       m_n = 0U;
-  } else {
-    sample = 0U;
   }
 
   m_pos++;
@@ -74,3 +75,6 @@ void CFMTimeout::stop()
 {
   m_running = false;
 }
+
+#endif
+

FMTimeout.h

@@ -16,11 +16,13 @@
  *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  */
 
+#include "Config.h"
+
+#if defined(MODE_FM)
+
 #if !defined(FMTimeout_H)
 #define  FMTimeout_H
 
-#include "Config.h"
-
 class CFMTimeout {
 public:
   CFMTimeout();
@@ -40,3 +42,6 @@ private:
 };
 
 #endif
+
+#endif
+

FMTimer.cpp

@@ -17,6 +17,9 @@
  */
 
 #include "Config.h"
+
+#if defined(MODE_FM)
+
 #include "Globals.h"
 #include "FMTimer.h"
 
@@ -68,3 +71,6 @@ bool CFMTimer::hasExpired() const
 
   return false;
 }
+
+#endif
+

FMTimer.h

@@ -16,11 +16,13 @@
  *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  */
 
+#include "Config.h"
+
+#if defined(MODE_FM)
+
 #if !defined(FMTimer_H)
 #define  FMTimer_H
 
-#include "Config.h"
-
 class CFMTimer {
 public:
   CFMTimer();
@@ -45,3 +47,6 @@ private:
 };
 
 #endif
+
+#endif
+

FMUpSampler.cpp

@@ -0,0 +1,104 @@
+/*
+ *   Copyright (C) 2020 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2020 by Geoffrey Merck F4FXL - KC3FRA
+ *
+ *   This program is free software; you can redistribute it and/or modify
+ *   it under the terms of the GNU General Public License as published by
+ *   the Free Software Foundation; either version 2 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ *
+ *   You should have received a copy of the GNU General Public License
+ *   along with this program; if not, write to the Free Software
+ *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include "Config.h"
+
+#if defined(MODE_FM)
+
+#include "FMUpSampler.h"
+
+const uint32_t FM_UPSAMPLE_MASK = 0x00000FFFU;
+
+CFMUpSampler::CFMUpSampler() :
+m_upSampleIndex(0),
+m_pack(0U),
+m_packPointer(NULL),
+m_samples(3600U), //300ms of 12 bit 8kHz audio
+m_running(false)
+{
+  m_packPointer = (uint8_t*)&m_pack;
+}
+
+void CFMUpSampler::reset()
+{
+    m_upSampleIndex = 0U;
+    m_pack = 0U;
+    m_samples.reset();
+    m_running = false;
+}
+
+void CFMUpSampler::addData(const uint8_t* data, uint16_t length)
+{
+  TSamplePairPack* packPointer = (TSamplePairPack*)data;
+  TSamplePairPack* packPointerEnd = packPointer + (length / 3U);
+  while(packPointer != packPointerEnd) {
+    m_samples.put(*packPointer);
+    packPointer++;
+  }
+  if(!m_running)
+    m_running = m_samples.getData() > 300U;//75ms of audio
+}
+
+bool CFMUpSampler::getSample(q15_t& sample)
+{
+  if(!m_running)
+    return false;
+
+  switch (m_upSampleIndex)
+  {
+  case 0: {
+    TSamplePairPack pairPack;
+    if(!m_samples.get(pairPack)) {
+      m_running = false;
+      return false;
+    }
+      
+    m_pack = 0U;
+    m_packPointer = (uint8_t*)&m_pack;
+
+    m_packPointer[0U] = pairPack.byte0;
+    m_packPointer[1U] = pairPack.byte1;
+    m_packPointer[2U] = pairPack.byte2;
+
+    sample = q15_t(m_pack >> 12) - 2048;
+    break;
+  }
+  case 3:
+    sample = q15_t(m_pack & FM_UPSAMPLE_MASK) - 2048;
+  break;
+  default:
+    sample = 0;
+  break;
+  }
+
+  m_upSampleIndex++;
+  if(m_upSampleIndex >= 6U)
+    m_upSampleIndex = 0U;
+
+  return true;
+}
+
+uint16_t CFMUpSampler::getSpace() const
+{
+  //return available space in bytes
+  return m_samples.getSpace() * sizeof(TSamplePairPack);
+}
+
+#endif
+

FMUpSampler.h

@@ -0,0 +1,54 @@
+/*
+ *   Copyright (C) 2020 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2020 by Geoffrey Merck F4FXL - KC3FRA
+ *
+ *   This program is free software; you can redistribute it and/or modify
+ *   it under the terms of the GNU General Public License as published by
+ *   the Free Software Foundation; either version 2 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ *
+ *   You should have received a copy of the GNU General Public License
+ *   along with this program; if not, write to the Free Software
+ *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+
+#include "Config.h"
+
+#if defined(MODE_FM)
+
+#if !defined(FMUPSAMPLER_H)
+#define FMUPSAMPLER_H
+
+#include "RingBuffer.h"
+#include "FMSamplePairPack.h"
+
+class CFMUpSampler {
+public:
+  CFMUpSampler();
+
+  void reset();
+
+  void addData(const uint8_t* data, uint16_t length);
+
+  bool getSample(q15_t& sample);
+
+  uint16_t getSpace() const;
+
+private:
+  uint8_t m_upSampleIndex;
+  uint32_t m_pack;
+  uint8_t * m_packPointer;
+  CRingBuffer<TSamplePairPack> m_samples;
+  bool m_running;
+};
+
+#endif
+
+#endif
+

Globals.h

@@ -28,6 +28,7 @@
 #include "STM32Utils.h"
 #else
 #include <Arduino.h>
+#undef PI //Undefine PI to get rid of annoying warning as it is also defined in arm_math.h.
 #endif
 
 #if defined(__SAM3X8E__) || defined(STM32F105xC)
@@ -50,7 +51,9 @@ enum MMDVM_STATE {
   STATE_P25       = 4,
   STATE_NXDN      = 5,
   STATE_POCSAG    = 6,
+  STATE_M17       = 7,
   STATE_FM        = 10,
+  STATE_AX25      = 11,
 
   // Dummy states start at 90
   STATE_NXDNCAL1K = 91,
@@ -84,6 +87,8 @@ enum MMDVM_STATE {
 #include "YSFTX.h"
 #include "P25RX.h"
 #include "P25TX.h"
+#include "M17RX.h"
+#include "M17TX.h"
 #include "NXDNRX.h"
 #include "NXDNTX.h"
 #include "POCSAGTX.h"
@@ -96,6 +101,8 @@ enum MMDVM_STATE {
 #include "CalPOCSAG.h"
 #include "CalRSSI.h"
 #include "CWIdTX.h"
+#include "AX25RX.h"
+#include "AX25TX.h"
 #include "Debug.h"
 #include "IO.h"
 #include "FM.h"
@@ -123,7 +130,9 @@ extern bool m_ysfEnable;
 extern bool m_p25Enable;
 extern bool m_nxdnEnable;
 extern bool m_pocsagEnable;
+extern bool m_m17Enable;
 extern bool m_fmEnable;
+extern bool m_ax25Enable;
 
 extern bool m_duplex;
 
@@ -133,9 +142,15 @@ extern bool m_dcd;
 extern CSerialPort serial;
 extern CIO io;
 
+#if defined(MODE_DSTAR)
 extern CDStarRX dstarRX;
 extern CDStarTX dstarTX;
 
+extern CCalDStarRX calDStarRX;
+extern CCalDStarTX calDStarTX;
+#endif
+
+#if defined(MODE_DMR)
 extern CDMRIdleRX dmrIdleRX;
 extern CDMRRX dmrRX;
 extern CDMRTX dmrTX;
@@ -143,28 +158,51 @@ extern CDMRTX dmrTX;
 extern CDMRDMORX dmrDMORX;
 extern CDMRDMOTX dmrDMOTX;
 
+extern CCalDMR calDMR;
+#endif
+
+#if defined(MODE_YSF)
 extern CYSFRX ysfRX;
 extern CYSFTX ysfTX;
+#endif
 
+#if defined(MODE_P25)
 extern CP25RX p25RX;
 extern CP25TX p25TX;
 
+extern CCalP25 calP25;
+#endif
+
+#if defined(MODE_NXDN)
 extern CNXDNRX nxdnRX;
 extern CNXDNTX nxdnTX;
 
-extern CPOCSAGTX pocsagTX;
+extern CCalNXDN calNXDN;
+#endif
 
-extern CFM fm;
+#if defined(MODE_POCSAG)
+extern CPOCSAGTX  pocsagTX;
+extern CCalPOCSAG calPOCSAG;
+#endif
 
-extern CCalDStarRX calDStarRX;
-extern CCalDStarTX calDStarTX;
-extern CCalDMR     calDMR;
-extern CCalFM      calFM;
-extern CCalP25     calP25;
-extern CCalNXDN    calNXDN;
-extern CCalPOCSAG  calPOCSAG;
-extern CCalRSSI    calRSSI;
+#if defined(MODE_M17)
+extern CM17RX m17RX;
+extern CM17TX m17TX;
+#endif
+
+#if defined(MODE_FM)
+extern CFM    fm;
+extern CCalFM calFM;
+#endif
+
+#if defined(MODE_AX25)
+extern CAX25RX ax25RX;
+extern CAX25TX ax25TX;
+#endif
+
+extern CCalRSSI calRSSI;
 
 extern CCWIdTX cwIdTX;
 
 #endif
+

IO.cpp

@@ -22,16 +22,34 @@
 #include "Globals.h"
 #include "IO.h"
 
+#if defined(USE_DCBLOCKER)
 // Generated using [b, a] = butter(1, 0.001) in MATLAB
 static q31_t   DC_FILTER[] = {3367972, 0, 3367972, 0, 2140747704, 0}; // {b0, 0, b1, b2, -a1, -a2}
 const uint32_t DC_FILTER_STAGES = 1U; // One Biquad stage
+#endif
 
+#if defined(MODE_DMR) || defined(MODE_YSF)
 // Generated using rcosdesign(0.2, 8, 5, 'sqrt') in MATLAB
 static q15_t RRC_0_2_FILTER[] = {401, 104, -340, -731, -847, -553, 112, 909, 1472, 1450, 683, -675, -2144, -3040, -2706, -770, 2667, 6995,
                                  11237, 14331, 15464, 14331, 11237, 6995, 2667, -770, -2706, -3040, -2144, -675, 683, 1450, 1472, 909, 112,
                                  -553, -847, -731, -340, 104, 401, 0};
 const uint16_t RRC_0_2_FILTER_LEN = 42U;
+#endif
 
+#if defined(MODE_M17)
+// Generated using rcosdesign(0.5, 8, 5, 'sqrt') in MATLAB
+static q15_t RRC_0_5_FILTER[] = {-147, -88, 72, 220, 223, 46, -197, -285, -79, 334, 623, 390, -498, -1691, -2363, -1556, 1284, 5872, 11033,
+				  15109, 16656, 15109, 11033, 5872, 1284, -1556, -2363, -1691, -498, 390, 623, 334, -79, -285, -197, 46, 223,
+				  220, 72, -88, -147, 0};
+const uint16_t RRC_0_5_FILTER_LEN = 42U;
+#endif
+
+#if defined(MODE_NXDN)
+#if defined(USE_NXDN_BOXCAR)
+// One symbol boxcar filter
+static q15_t   BOXCAR10_FILTER[] = {6000, 6000, 6000, 6000, 6000, 6000, 6000, 6000, 6000, 6000};
+const uint16_t BOXCAR10_FILTER_LEN = 10U;
+#else
 // Generated using rcosdesign(0.2, 8, 10, 'sqrt') in MATLAB
 static q15_t NXDN_0_2_FILTER[] = {284, 198, 73, -78, -240, -393, -517, -590, -599, -533, -391, -181, 79, 364, 643, 880, 1041, 1097, 1026, 819,
                                   483, 39, -477, -1016, -1516, -1915, -2150, -2164, -1914, -1375, -545, 557, 1886, 3376, 4946, 6502, 7946, 9184,
@@ -43,14 +61,20 @@ const uint16_t NXDN_0_2_FILTER_LEN = 82U;
 static q15_t NXDN_ISINC_FILTER[] = {790, -1085, -1073, -553, 747, 2341, 3156, 2152, -893, -4915, -7834, -7536, -3102, 4441, 12354, 17394, 17394,
                                    12354, 4441, -3102, -7536, -7834, -4915, -893, 2152, 3156, 2341, 747, -553, -1073, -1085, 790};
 const uint16_t NXDN_ISINC_FILTER_LEN = 32U;
+#endif
+#endif
 
+#if defined(MODE_DSTAR)
 // Generated using gaussfir(0.5, 4, 5) in MATLAB
 static q15_t   GAUSSIAN_0_5_FILTER[] = {8, 104, 760, 3158, 7421, 9866, 7421, 3158, 760, 104, 8, 0};
 const uint16_t GAUSSIAN_0_5_FILTER_LEN = 12U;
+#endif
 
+#if defined(MODE_P25)
 // One symbol boxcar filter
-static q15_t   BOXCAR_FILTER[] = {12000, 12000, 12000, 12000, 12000, 0};
-const uint16_t BOXCAR_FILTER_LEN = 6U;
+static q15_t   BOXCAR5_FILTER[] = {12000, 12000, 12000, 12000, 12000, 0};
+const uint16_t BOXCAR5_FILTER_LEN = 6U;
+#endif
 
 const uint16_t DC_OFFSET = 2048U;
 
@@ -59,18 +83,37 @@ m_started(false),
 m_rxBuffer(RX_RINGBUFFER_SIZE),
 m_txBuffer(TX_RINGBUFFER_SIZE),
 m_rssiBuffer(RX_RINGBUFFER_SIZE),
+#if defined(USE_DCBLOCKER)
 m_dcFilter(),
 m_dcState(),
-m_rrcFilter(),
+#endif
+#if defined(MODE_DSTAR)
 m_gaussianFilter(),
-m_boxcarFilter(),
+m_gaussianState(),
+#endif
+#if defined(MODE_DMR) || defined(MODE_YSF)
+m_rrc02Filter(),
+m_rrc02State(),
+#endif
+#if defined(MODE_P25)
+m_boxcar5Filter(),
+m_boxcar5State(),
+#endif
+#if defined(MODE_NXDN)
+#if defined(USE_NXDN_BOXCAR)
+m_boxcar10Filter(),
+m_boxcar10State(),
+#else
 m_nxdnFilter(),
 m_nxdnISincFilter(),
-m_rrcState(),
-m_gaussianState(),
-m_boxcarState(),
 m_nxdnState(),
 m_nxdnISincState(),
+#endif
+#endif
+#if defined(MODE_M17)
+m_rrc05Filter(),
+m_rrc05State(),
+#endif
 m_pttInvert(false),
 m_rxLevel(128 * 128),
 m_cwIdTXLevel(128 * 128),
@@ -79,10 +122,13 @@ m_dmrTXLevel(128 * 128),
 m_ysfTXLevel(128 * 128),
 m_p25TXLevel(128 * 128),
 m_nxdnTXLevel(128 * 128),
+m_m17TXLevel(128 * 128),
 m_pocsagTXLevel(128 * 128),
 m_fmTXLevel(128 * 128),
+m_ax25TXLevel(128 * 128),
 m_rxDCOffset(DC_OFFSET),
 m_txDCOffset(DC_OFFSET),
+m_useCOSAsLockout(false),
 m_ledCount(0U),
 m_ledValue(true),
 m_detect(false),
@@ -91,30 +137,45 @@ m_dacOverflow(0U),
 m_watchdog(0U),
 m_lockout(false)
 {
-  ::memset(m_rrcState,      0x00U,  70U * sizeof(q15_t));
-  ::memset(m_gaussianState, 0x00U,  40U * sizeof(q15_t));
-  ::memset(m_boxcarState,   0x00U,  30U * sizeof(q15_t));
-  ::memset(m_nxdnState,     0x00U, 110U * sizeof(q15_t));
-  ::memset(m_nxdnISincState, 0x00U, 60U * sizeof(q15_t));
+#if defined(USE_DCBLOCKER)
   ::memset(m_dcState,       0x00U,   4U * sizeof(q31_t));
-
   m_dcFilter.numStages = DC_FILTER_STAGES;
   m_dcFilter.pState    = m_dcState;
   m_dcFilter.pCoeffs   = DC_FILTER;
   m_dcFilter.postShift = 0;
+#endif
 
-  m_rrcFilter.numTaps = RRC_0_2_FILTER_LEN;
-  m_rrcFilter.pState  = m_rrcState;
-  m_rrcFilter.pCoeffs = RRC_0_2_FILTER;
-
+#if defined(MODE_DSTAR)
+  ::memset(m_gaussianState, 0x00U, 40U * sizeof(q15_t));
   m_gaussianFilter.numTaps = GAUSSIAN_0_5_FILTER_LEN;
   m_gaussianFilter.pState  = m_gaussianState;
   m_gaussianFilter.pCoeffs = GAUSSIAN_0_5_FILTER;
+#endif
+
+#if defined(MODE_DMR) || defined(MODE_YSF)
+  ::memset(m_rrc02State, 0x00U, 70U * sizeof(q15_t));
+  m_rrc02Filter.numTaps = RRC_0_2_FILTER_LEN;
+  m_rrc02Filter.pState  = m_rrc02State;
+  m_rrc02Filter.pCoeffs = RRC_0_2_FILTER;
+#endif
+
+#if defined(MODE_P25)
+  ::memset(m_boxcar5State, 0x00U, 30U * sizeof(q15_t));
+  m_boxcar5Filter.numTaps = BOXCAR5_FILTER_LEN;
+  m_boxcar5Filter.pState  = m_boxcar5State;
+  m_boxcar5Filter.pCoeffs = BOXCAR5_FILTER;
+#endif
+
+#if defined(MODE_NXDN)
+#if defined(USE_NXDN_BOXCAR)
+  ::memset(m_boxcar10State, 0x00U, 40U * sizeof(q15_t));
+  m_boxcar10Filter.numTaps = BOXCAR10_FILTER_LEN;
+  m_boxcar10Filter.pState  = m_boxcar10State;
+  m_boxcar10Filter.pCoeffs = BOXCAR10_FILTER;
+#else
+  ::memset(m_nxdnState,      0x00U, 110U * sizeof(q15_t));
+  ::memset(m_nxdnISincState, 0x00U, 60U * sizeof(q15_t));
 
-  m_boxcarFilter.numTaps = BOXCAR_FILTER_LEN;
-  m_boxcarFilter.pState  = m_boxcarState;
-  m_boxcarFilter.pCoeffs = BOXCAR_FILTER;
-  
   m_nxdnFilter.numTaps = NXDN_0_2_FILTER_LEN;
   m_nxdnFilter.pState  = m_nxdnState;
   m_nxdnFilter.pCoeffs = NXDN_0_2_FILTER;
@@ -122,6 +183,15 @@ m_lockout(false)
   m_nxdnISincFilter.numTaps = NXDN_ISINC_FILTER_LEN;
   m_nxdnISincFilter.pState  = m_nxdnISincState;
   m_nxdnISincFilter.pCoeffs = NXDN_ISINC_FILTER;
+#endif
+#endif
+
+#if defined(MODE_M17)
+  ::memset(m_rrc05State, 0x00U, 70U * sizeof(q15_t));
+  m_rrc05Filter.numTaps = RRC_0_5_FILTER_LEN;
+  m_rrc05Filter.pState  = m_rrc05State;
+  m_rrc05Filter.pCoeffs = RRC_0_5_FILTER;
+#endif
 
   initInt();
   
@@ -132,7 +202,7 @@ void CIO::selfTest()
 {
   bool ledValue = false;
 
-  for (uint8_t i = 0; i < 6; i++) {
+  for (uint8_t i = 0U; i < 6U; i++) {
     ledValue = !ledValue;
 
     // We exclude PTT to avoid trigger the transmitter
@@ -143,21 +213,40 @@ void CIO::selfTest()
     setDMRInt(ledValue);
     setYSFInt(ledValue);
     setP25Int(ledValue);
+#if !defined(USE_ALTERNATE_NXDN_LEDS)
     setNXDNInt(ledValue);
+#endif
+#if !defined(USE_ALTERNATE_M17_LEDS)
+    setM17Int(ledValue);
+#endif
+#if !defined(USE_ALTERNATE_POCSAG_LEDS)
     setPOCSAGInt(ledValue);
+#endif
+#if !defined(USE_ALTERNATE_FM_LEDS)
     setFMInt(ledValue);
+#endif
 #endif
     delayInt(250);
   }
 
 #if defined(MODE_LEDS)
-  setDStarInt(true);
+  setDStarInt(false);
   setDMRInt(false);
   setYSFInt(false);
   setP25Int(false);
+#if !defined(USE_ALTERNATE_NXDN_LEDS)
   setNXDNInt(false);
+#endif
+#if !defined(USE_ALTERNATE_M17_LEDS)
+  setM17Int(false);
+#endif
+#if !defined(USE_ALTERNATE_POCSAG_LEDS)
   setPOCSAGInt(false);
+#endif
+#if !defined(USE_ALTERNATE_FM_LEDS)
   setFMInt(false);
+#endif
+  setDStarInt(true);
 
   delayInt(250);
   setDMRInt(true);
@@ -173,6 +262,11 @@ void CIO::selfTest()
   setNXDNInt(true);
 #endif
 
+#if !defined(USE_ALTERNATE_M17_LEDS)
+  delayInt(250);
+  setM17Int(true);
+#endif
+
 #if !defined(USE_ALTERNATE_POCSAG_LEDS)
   delayInt(250);
   setPOCSAGInt(true);
@@ -191,6 +285,11 @@ void CIO::selfTest()
   setPOCSAGInt(false);
 #endif
 
+#if !defined(USE_ALTERNATE_M17_LEDS)
+  delayInt(250);
+  setM17Int(false);
+#endif
+
 #if !defined(USE_ALTERNATE_NXDN_LEDS)
   delayInt(250);
   setNXDNInt(false);
@@ -219,7 +318,7 @@ void CIO::start()
 
   m_started = true;
 
-  setMode();
+  setMode(STATE_IDLE);
 }
 
 void CIO::process()
@@ -228,11 +327,12 @@ void CIO::process()
   if (m_started) {
     // Two seconds timeout
     if (m_watchdog >= 48000U) {
-      if (m_modemState == STATE_DSTAR || m_modemState == STATE_DMR || m_modemState == STATE_YSF || m_modemState == STATE_P25 || m_modemState == STATE_NXDN || m_modemState == STATE_POCSAG) {
+      if (m_modemState == STATE_DSTAR || m_modemState == STATE_DMR || m_modemState == STATE_YSF || m_modemState == STATE_P25 || m_modemState == STATE_NXDN || m_modemState == STATE_M17 || m_modemState == STATE_POCSAG) {
+#if defined(MODE_DMR)
         if (m_modemState == STATE_DMR && m_tx)
           dmrTX.setStart(false);
-        m_modemState = STATE_IDLE;
-        setMode();
+#endif
+        setMode(STATE_IDLE);
       }
 
       m_watchdog = 0U;
@@ -256,14 +356,14 @@ void CIO::process()
     return;
   }
 
-#if defined(USE_COS_AS_LOCKOUT)
-  m_lockout = getCOSInt();
-#endif
+  if (m_useCOSAsLockout)
+    m_lockout = getCOSInt();
 
   // Switch off the transmitter if needed
   if (m_txBuffer.getData() == 0U && m_tx) {
     m_tx = false;
     setPTTInt(m_pttInvert ? true : false);
+    DEBUG1("TX OFF");
   }
 
   if (m_rxBuffer.getData() >= RX_BLOCK_SIZE) {
@@ -272,15 +372,16 @@ void CIO::process()
     uint16_t rssi[RX_BLOCK_SIZE];
 
     for (uint16_t i = 0U; i < RX_BLOCK_SIZE; i++) {
-      uint16_t sample;
-      m_rxBuffer.get(sample, control[i]);
+      TSample sample;
+      m_rxBuffer.get(sample);
+      control[i] = sample.control;
       m_rssiBuffer.get(rssi[i]);
 
       // Detect ADC overflow
-      if (m_detect && (sample == 0U || sample == 4095U))
+      if (m_detect && (sample.sample == 0U || sample.sample == 4095U))
         m_adcOverflow++;
 
-      q15_t res1 = q15_t(sample) - m_rxDCOffset;
+      q15_t res1 = q15_t(sample.sample) - m_rxDCOffset;
       q31_t res2 = res1 * m_rxLevel;
       samples[i] = q15_t(__SSAT((res2 >> 15), 16));
     }
@@ -308,6 +409,7 @@ void CIO::process()
 #endif
 
     if (m_modemState == STATE_IDLE) {
+#if defined(MODE_DSTAR)
       if (m_dstarEnable) {
         q15_t GMSKVals[RX_BLOCK_SIZE];
 #if defined(USE_DCBLOCKER)
@@ -317,45 +419,79 @@ void CIO::process()
 #endif
         dstarRX.samples(GMSKVals, rssi, RX_BLOCK_SIZE);
       }
+#endif
 
+#if defined(MODE_P25)
       if (m_p25Enable) {
         q15_t P25Vals[RX_BLOCK_SIZE];
 #if defined(USE_DCBLOCKER)
-        ::arm_fir_fast_q15(&m_boxcarFilter, dcSamples, P25Vals, RX_BLOCK_SIZE);
+        ::arm_fir_fast_q15(&m_boxcar5Filter, dcSamples, P25Vals, RX_BLOCK_SIZE);
 #else
-        ::arm_fir_fast_q15(&m_boxcarFilter, samples, P25Vals, RX_BLOCK_SIZE);
+        ::arm_fir_fast_q15(&m_boxcar5Filter, samples, P25Vals, RX_BLOCK_SIZE);
 #endif
         p25RX.samples(P25Vals, rssi, RX_BLOCK_SIZE);
       }
+#endif
 
+#if defined(MODE_NXDN)
       if (m_nxdnEnable) {
+        q15_t NXDNVals[RX_BLOCK_SIZE];
+#if defined(USE_NXDN_BOXCAR)
+#if defined(USE_DCBLOCKER)
+        ::arm_fir_fast_q15(&m_boxcar10Filter, dcSamples, NXDNVals, RX_BLOCK_SIZE);
+#else
+        ::arm_fir_fast_q15(&m_boxcar10Filter, samples, NXDNVals, RX_BLOCK_SIZE);
+#endif
+#else
         q15_t NXDNValsTmp[RX_BLOCK_SIZE];
 #if defined(USE_DCBLOCKER)
         ::arm_fir_fast_q15(&m_nxdnFilter, dcSamples, NXDNValsTmp, RX_BLOCK_SIZE);
 #else
         ::arm_fir_fast_q15(&m_nxdnFilter, samples, NXDNValsTmp, RX_BLOCK_SIZE);
 #endif
-        q15_t NXDNVals[RX_BLOCK_SIZE];
         ::arm_fir_fast_q15(&m_nxdnISincFilter, NXDNValsTmp, NXDNVals, RX_BLOCK_SIZE);
-
+#endif
         nxdnRX.samples(NXDNVals, rssi, RX_BLOCK_SIZE);
       }
+#endif
 
-      if (m_dmrEnable || m_ysfEnable) {
-        q15_t RRCVals[RX_BLOCK_SIZE];
-        ::arm_fir_fast_q15(&m_rrcFilter, samples, RRCVals, RX_BLOCK_SIZE);
+#if defined(MODE_DMR)
+      if (m_dmrEnable) {
+        q15_t DMRVals[RX_BLOCK_SIZE];
+        ::arm_fir_fast_q15(&m_rrc02Filter, samples, DMRVals, RX_BLOCK_SIZE);
 
-        if (m_ysfEnable)
-          ysfRX.samples(RRCVals, rssi, RX_BLOCK_SIZE);
-
-        if (m_dmrEnable) {
-          if (m_duplex)
-            dmrIdleRX.samples(RRCVals, RX_BLOCK_SIZE);
-          else
-            dmrDMORX.samples(RRCVals, rssi, RX_BLOCK_SIZE);
-        }
+        if (m_duplex)
+          dmrIdleRX.samples(DMRVals, RX_BLOCK_SIZE);
+        else
+          dmrDMORX.samples(DMRVals, rssi, RX_BLOCK_SIZE);
       }
+#endif
 
+#if defined(MODE_YSF)
+      if (m_ysfEnable) {
+        q15_t YSFVals[RX_BLOCK_SIZE];
+#if defined(USE_DCBLOCKER)
+        ::arm_fir_fast_q15(&m_rrc02Filter, dcSamples, YSFVals, RX_BLOCK_SIZE);
+#else
+        ::arm_fir_fast_q15(&m_rrc02Filter, samples, YSFVals, RX_BLOCK_SIZE);
+#endif
+        ysfRX.samples(YSFVals, rssi, RX_BLOCK_SIZE);
+      }
+#endif
+
+#if defined(MODE_M17)
+      if (m_m17Enable) {
+        q15_t RRCVals[RX_BLOCK_SIZE];
+#if defined(USE_DCBLOCKER)
+        ::arm_fir_fast_q15(&m_rrc05Filter, dcSamples, RRCVals, RX_BLOCK_SIZE);
+#else
+        ::arm_fir_fast_q15(&m_rrc05Filter, samples, RRCVals, RX_BLOCK_SIZE);
+#endif
+        m17RX.samples(RRCVals, rssi, RX_BLOCK_SIZE);
+      }
+#endif
+
+#if defined(MODE_FM)
       if (m_fmEnable) {
         bool cos = getCOSInt();
 #if defined(USE_DCBLOCKER)
@@ -364,7 +500,21 @@ void CIO::process()
         fm.samples(cos, samples, RX_BLOCK_SIZE);
 #endif
       }
-    } else if (m_modemState == STATE_DSTAR) {
+#endif
+
+#if defined(MODE_FM) && defined(MODE_AX25)
+      if (m_ax25Enable) {
+#if defined(USE_DCBLOCKER)
+        ax25RX.samples(dcSamples, RX_BLOCK_SIZE);
+#else
+        ax25RX.samples(samples, RX_BLOCK_SIZE);
+#endif
+      }
+#endif
+    }
+
+#if defined(MODE_DSTAR)
+    else if (m_modemState == STATE_DSTAR) {
       if (m_dstarEnable) {
         q15_t GMSKVals[RX_BLOCK_SIZE];
 #if defined(USE_DCBLOCKER)
@@ -374,10 +524,14 @@ void CIO::process()
 #endif
         dstarRX.samples(GMSKVals, rssi, RX_BLOCK_SIZE);
       }
-    } else if (m_modemState == STATE_DMR) {
+    }
+#endif
+
+#if defined(MODE_DMR)
+    else if (m_modemState == STATE_DMR) {
       if (m_dmrEnable) {
         q15_t DMRVals[RX_BLOCK_SIZE];
-        ::arm_fir_fast_q15(&m_rrcFilter, samples, DMRVals, RX_BLOCK_SIZE);
+        ::arm_fir_fast_q15(&m_rrc02Filter, samples, DMRVals, RX_BLOCK_SIZE);
 
         if (m_duplex) {
           // If the transmitter isn't on, use the DMR idle RX to detect the wakeup CSBKs
@@ -389,52 +543,106 @@ void CIO::process()
           dmrDMORX.samples(DMRVals, rssi, RX_BLOCK_SIZE);
         }
       }
-    } else if (m_modemState == STATE_YSF) {
+    }
+#endif
+
+#if defined(MODE_YSF)
+    else if (m_modemState == STATE_YSF) {
       if (m_ysfEnable) {
         q15_t YSFVals[RX_BLOCK_SIZE];
 #if defined(USE_DCBLOCKER)
-        ::arm_fir_fast_q15(&m_rrcFilter, dcSamples, YSFVals, RX_BLOCK_SIZE);
+        ::arm_fir_fast_q15(&m_rrc02Filter, dcSamples, YSFVals, RX_BLOCK_SIZE);
 #else
-        ::arm_fir_fast_q15(&m_rrcFilter, samples, YSFVals, RX_BLOCK_SIZE);
+        ::arm_fir_fast_q15(&m_rrc02Filter, samples, YSFVals, RX_BLOCK_SIZE);
 #endif
         ysfRX.samples(YSFVals, rssi, RX_BLOCK_SIZE);
       }
-    } else if (m_modemState == STATE_P25) {
+    }
+#endif
+
+#if defined(MODE_P25)
+    else if (m_modemState == STATE_P25) {
       if (m_p25Enable) {
         q15_t P25Vals[RX_BLOCK_SIZE];
 #if defined(USE_DCBLOCKER)
-        ::arm_fir_fast_q15(&m_boxcarFilter, dcSamples, P25Vals, RX_BLOCK_SIZE);
+        ::arm_fir_fast_q15(&m_boxcar5Filter, dcSamples, P25Vals, RX_BLOCK_SIZE);
 #else
-        ::arm_fir_fast_q15(&m_boxcarFilter, samples, P25Vals, RX_BLOCK_SIZE);
+        ::arm_fir_fast_q15(&m_boxcar5Filter, samples, P25Vals, RX_BLOCK_SIZE);
 #endif
         p25RX.samples(P25Vals, rssi, RX_BLOCK_SIZE);
       }
-    } else if (m_modemState == STATE_NXDN) {
+    }
+#endif
+
+#if defined(MODE_NXDN)
+    else if (m_modemState == STATE_NXDN) {
       if (m_nxdnEnable) {
+        q15_t NXDNVals[RX_BLOCK_SIZE];
+#if defined(USE_NXDN_BOXCAR)
+#if defined(USE_DCBLOCKER)
+        ::arm_fir_fast_q15(&m_boxcar10Filter, dcSamples, NXDNVals, RX_BLOCK_SIZE);
+#else
+        ::arm_fir_fast_q15(&m_boxcar10Filter, samples, NXDNVals, RX_BLOCK_SIZE);
+#endif
+#else
         q15_t NXDNValsTmp[RX_BLOCK_SIZE];
 #if defined(USE_DCBLOCKER)
         ::arm_fir_fast_q15(&m_nxdnFilter, dcSamples, NXDNValsTmp, RX_BLOCK_SIZE);
 #else
         ::arm_fir_fast_q15(&m_nxdnFilter, samples, NXDNValsTmp, RX_BLOCK_SIZE);
 #endif
-        q15_t NXDNVals[RX_BLOCK_SIZE];
         ::arm_fir_fast_q15(&m_nxdnISincFilter, NXDNValsTmp, NXDNVals, RX_BLOCK_SIZE);
-
+#endif
         nxdnRX.samples(NXDNVals, rssi, RX_BLOCK_SIZE);
       }
-    } else if (m_modemState == STATE_FM) {
+    }
+#endif
+
+#if defined(MODE_M17)
+    else if (m_modemState == STATE_M17) {
+      if (m_m17Enable) {
+        q15_t M17Vals[RX_BLOCK_SIZE];
+#if defined(USE_DCBLOCKER)
+        ::arm_fir_fast_q15(&m_rrc05Filter, dcSamples, M17Vals, RX_BLOCK_SIZE);
+#else
+        ::arm_fir_fast_q15(&m_rrc05Filter, samples, M17Vals, RX_BLOCK_SIZE);
+#endif
+        m17RX.samples(M17Vals, rssi, RX_BLOCK_SIZE);
+      }
+    }
+#endif
+
+#if defined(MODE_FM)
+    else if (m_modemState == STATE_FM) {
       bool cos = getCOSInt();
 #if defined(USE_DCBLOCKER)
       fm.samples(cos, dcSamples, RX_BLOCK_SIZE);
+
+#if defined(MODE_AX25)
+      if (m_ax25Enable)
+        ax25RX.samples(dcSamples, RX_BLOCK_SIZE);
+#endif
 #else
       fm.samples(cos, samples, RX_BLOCK_SIZE);
+
+#if defined(MODE_AX25)
+      if (m_ax25Enable)
+        ax25RX.samples(samples, RX_BLOCK_SIZE);
 #endif
-    } else if (m_modemState == STATE_DSTARCAL) {
+#endif
+    }
+#endif
+
+#if defined(MODE_DSTAR)
+    else if (m_modemState == STATE_DSTARCAL) {
       q15_t GMSKVals[RX_BLOCK_SIZE];
       ::arm_fir_fast_q15(&m_gaussianFilter, samples, GMSKVals, RX_BLOCK_SIZE);
 
       calDStarRX.samples(GMSKVals, RX_BLOCK_SIZE);
-    } else if (m_modemState == STATE_RSSICAL) {
+    }
+#endif
+
+    else if (m_modemState == STATE_RSSICAL) {
       calRSSI.samples(rssi, RX_BLOCK_SIZE);
     }
   }
@@ -452,6 +660,7 @@ void CIO::write(MMDVM_STATE mode, q15_t* samples, uint16_t length, const uint8_t
   if (!m_tx) {
     m_tx = true;
     setPTTInt(m_pttInvert ? false : true);
+    DEBUG1("TX ON");
   }
 
   q15_t txLevel = 0;
@@ -471,12 +680,18 @@ void CIO::write(MMDVM_STATE mode, q15_t* samples, uint16_t length, const uint8_t
     case STATE_NXDN:
       txLevel = m_nxdnTXLevel;
       break;
+    case STATE_M17:
+      txLevel = m_m17TXLevel;
+      break;
     case STATE_POCSAG:
       txLevel = m_pocsagTXLevel;
       break;
     case STATE_FM:
       txLevel = m_fmTXLevel;
       break;
+    case STATE_AX25:
+      txLevel = m_ax25TXLevel;
+      break;
     default:
       txLevel = m_cwIdTXLevel;
       break;
@@ -492,9 +707,9 @@ void CIO::write(MMDVM_STATE mode, q15_t* samples, uint16_t length, const uint8_t
       m_dacOverflow++;
 
     if (control == NULL)
-      m_txBuffer.put(res3, MARK_NONE);
+      m_txBuffer.put({res3, MARK_NONE});
     else
-      m_txBuffer.put(res3, control[i]);
+      m_txBuffer.put({res3, control[i]});
   }
 }
 
@@ -516,20 +731,41 @@ void CIO::setADCDetection(bool detect)
   m_detect = detect;
 }
 
-void CIO::setMode()
+void CIO::setMode(MMDVM_STATE state)
 {
+  if (state == m_modemState)
+    return;
+
 #if defined(MODE_LEDS)
-  setDStarInt(m_modemState == STATE_DSTAR);
-  setDMRInt(m_modemState   == STATE_DMR);
-  setYSFInt(m_modemState   == STATE_YSF);
-  setP25Int(m_modemState   == STATE_P25);
-  setNXDNInt(m_modemState  == STATE_NXDN);
-  setPOCSAGInt(m_modemState  == STATE_POCSAG);
-  setFMInt(m_modemState == STATE_FM);
+  switch (m_modemState) {
+    case STATE_DSTAR:  setDStarInt(false);  break;
+    case STATE_DMR:    setDMRInt(false);    break;
+    case STATE_YSF:    setYSFInt(false);    break;
+    case STATE_P25:    setP25Int(false);    break;
+    case STATE_NXDN:   setNXDNInt(false);   break;
+    case STATE_M17:    setM17Int(false);    break;
+    case STATE_POCSAG: setPOCSAGInt(false); break;
+    case STATE_FM:     setFMInt(false);     break;
+    default: break;
+  }
+
+  switch (state) {
+    case STATE_DSTAR:  setDStarInt(true);  break;
+    case STATE_DMR:    setDMRInt(true);    break;
+    case STATE_YSF:    setYSFInt(true);    break;
+    case STATE_P25:    setP25Int(true);    break;
+    case STATE_NXDN:   setNXDNInt(true);   break;
+    case STATE_M17:    setM17Int(true);    break;
+    case STATE_POCSAG: setPOCSAGInt(true); break;
+    case STATE_FM:     setFMInt(true);     break;
+    default: break;
+  }
 #endif
+
+  m_modemState = state;
 }
 
-void CIO::setParameters(bool rxInvert, bool txInvert, bool pttInvert, uint8_t rxLevel, uint8_t cwIdTXLevel, uint8_t dstarTXLevel, uint8_t dmrTXLevel, uint8_t ysfTXLevel, uint8_t p25TXLevel, uint8_t nxdnTXLevel, uint8_t pocsagTXLevel, uint8_t fmTXLevel, int16_t txDCOffset, int16_t rxDCOffset)
+void CIO::setParameters(bool rxInvert, bool txInvert, bool pttInvert, uint8_t rxLevel, uint8_t cwIdTXLevel, uint8_t dstarTXLevel, uint8_t dmrTXLevel, uint8_t ysfTXLevel, uint8_t p25TXLevel, uint8_t nxdnTXLevel, uint8_t m17TXLevel, uint8_t pocsagTXLevel, uint8_t fmTXLevel, uint8_t ax25TXLevel, int16_t txDCOffset, int16_t rxDCOffset, bool useCOSAsLockout)
 {
   m_pttInvert = pttInvert;
 
@@ -540,11 +776,15 @@ void CIO::setParameters(bool rxInvert, bool txInvert, bool pttInvert, uint8_t rx
   m_ysfTXLevel    = q15_t(ysfTXLevel * 128);
   m_p25TXLevel    = q15_t(p25TXLevel * 128);
   m_nxdnTXLevel   = q15_t(nxdnTXLevel * 128);
+  m_m17TXLevel    = q15_t(m17TXLevel * 128);
   m_pocsagTXLevel = q15_t(pocsagTXLevel * 128);
   m_fmTXLevel     = q15_t(fmTXLevel * 128);
+  m_ax25TXLevel   = q15_t(ax25TXLevel * 128);
 
   m_rxDCOffset   = DC_OFFSET + rxDCOffset;
   m_txDCOffset   = DC_OFFSET + txDCOffset;
+
+  m_useCOSAsLockout = useCOSAsLockout;
   
   if (rxInvert)
     m_rxLevel = -m_rxLevel;
@@ -555,6 +795,7 @@ void CIO::setParameters(bool rxInvert, bool txInvert, bool pttInvert, uint8_t rx
     m_ysfTXLevel    = -m_ysfTXLevel;
     m_p25TXLevel    = -m_p25TXLevel;
     m_nxdnTXLevel   = -m_nxdnTXLevel;
+    m_m17TXLevel    = -m_m17TXLevel;
     m_pocsagTXLevel = -m_pocsagTXLevel;
   }
 }

IO.h

@@ -21,8 +21,12 @@
 
 #include "Globals.h"
 
-#include "SampleRB.h"
-#include "RSSIRB.h"
+#include "RingBuffer.h"
+
+struct TSample {
+  volatile uint16_t sample;
+  volatile uint8_t control;
+};
 
 class CIO {
 public:
@@ -38,11 +42,11 @@ public:
 
   void setDecode(bool dcd);
   void setADCDetection(bool detect);
-  void setMode();
+  void setMode(MMDVM_STATE state);
   
   void interrupt();
 
-  void setParameters(bool rxInvert, bool txInvert, bool pttInvert, uint8_t rxLevel, uint8_t cwIdTXLevel, uint8_t dstarTXLevel, uint8_t dmrTXLevel, uint8_t ysfTXLevel, uint8_t p25TXLevel, uint8_t nxdnTXLevel, uint8_t pocsagTXLevel, uint8_t fmTXLevel, int16_t txDCOffset, int16_t rxDCOffset);
+  void setParameters(bool rxInvert, bool txInvert, bool pttInvert, uint8_t rxLevel, uint8_t cwIdTXLevel, uint8_t dstarTXLevel, uint8_t dmrTXLevel, uint8_t ysfTXLevel, uint8_t p25TXLevel, uint8_t nxdnTXLevel, uint8_t m17TXLevel, uint8_t pocsagTXLevel, uint8_t fmTXLevel, uint8_t ax25TXLevel, int16_t txDCOffset, int16_t rxDCOffset, bool useCOSAsLockout);
 
   void getOverflow(bool& adcOverflow, bool& dacOverflow);
 
@@ -54,28 +58,55 @@ public:
   void resetWatchdog();
   uint32_t getWatchdog();
   
+  uint8_t getCPU() const;
+
+  void getUDID(uint8_t* buffer);
+
   void selfTest();
 
 private:
-  bool                 m_started;
+  bool                  m_started;
 
-  CSampleRB            m_rxBuffer;
-  CSampleRB            m_txBuffer;
-  CRSSIRB              m_rssiBuffer;
+  CRingBuffer<TSample>  m_rxBuffer;
+  CRingBuffer<TSample>  m_txBuffer;
+  CRingBuffer<uint16_t> m_rssiBuffer;
 
+#if defined(USE_DCBLOCKER)
   arm_biquad_casd_df1_inst_q31 m_dcFilter;
   q31_t                        m_dcState[4];
+#endif
 
-  arm_fir_instance_q15 m_rrcFilter;
+#if defined(MODE_DSTAR)
   arm_fir_instance_q15 m_gaussianFilter;
-  arm_fir_instance_q15 m_boxcarFilter;
+  q15_t                m_gaussianState[40U];      // NoTaps + BlockSize - 1, 12 + 20 - 1 plus some spare
+#endif
+
+#if defined(MODE_DMR) || defined(MODE_YSF)
+  arm_fir_instance_q15 m_rrc02Filter;
+  q15_t                m_rrc02State[70U];         // NoTaps + BlockSize - 1, 42 + 20 - 1 plus some spare
+#endif
+
+#if defined(MODE_P25)
+  arm_fir_instance_q15 m_boxcar5Filter;
+  q15_t                m_boxcar5State[30U];        // NoTaps + BlockSize - 1,  6 + 20 - 1 plus some spare
+#endif
+
+#if defined(MODE_NXDN)
+#if defined(USE_NXDN_BOXCAR)
+  arm_fir_instance_q15 m_boxcar10Filter;
+  q15_t                m_boxcar10State[40U];      // NoTaps + BlockSize - 1, 10 + 20 - 1 plus some spare
+#else
   arm_fir_instance_q15 m_nxdnFilter;
   arm_fir_instance_q15 m_nxdnISincFilter;
-  q15_t                m_rrcState[70U];           // NoTaps + BlockSize - 1, 42 + 20 - 1 plus some spare
-  q15_t                m_gaussianState[40U];      // NoTaps + BlockSize - 1, 12 + 20 - 1 plus some spare
-  q15_t                m_boxcarState[30U];        // NoTaps + BlockSize - 1, 6 + 20 - 1 plus some spare
   q15_t                m_nxdnState[110U];         // NoTaps + BlockSize - 1, 82 + 20 - 1 plus some spare
   q15_t                m_nxdnISincState[60U];     // NoTaps + BlockSize - 1, 32 + 20 - 1 plus some spare
+#endif
+#endif
+
+#if defined(MODE_M17)
+  arm_fir_instance_q15 m_rrc05Filter;
+  q15_t                m_rrc05State[70U];         // NoTaps + BlockSize - 1, 42 + 20 - 1 plus some spare
+#endif
 
   bool                 m_pttInvert;
   q15_t                m_rxLevel;
@@ -85,12 +116,16 @@ private:
   q15_t                m_ysfTXLevel;
   q15_t                m_p25TXLevel;
   q15_t                m_nxdnTXLevel;
+  q15_t                m_m17TXLevel;
   q15_t                m_pocsagTXLevel;
   q15_t                m_fmTXLevel;
+  q15_t                m_ax25TXLevel;
 
   uint16_t             m_rxDCOffset;
   uint16_t             m_txDCOffset;
 
+  bool                 m_useCOSAsLockout;
+
   uint32_t             m_ledCount;
   bool                 m_ledValue;
 
@@ -119,6 +154,7 @@ private:
   void setP25Int(bool on);
   void setNXDNInt(bool on);
   void setPOCSAGInt(bool on);
+  void setM17Int(bool on);
   void setFMInt(bool on);
   
   void delayInt(unsigned int dly);

IODue.cpp

@@ -107,6 +107,9 @@ void CIO::initInt()
 #if !defined(USE_ALTERNATE_NXDN_LEDS)
   pinMode(PIN_NXDN,   OUTPUT);
 #endif
+#if !defined(USE_ALTERNATE_M17_LEDS)
+  pinMode(PIN_M17,    OUTPUT);
+#endif
 #if !defined(USE_ALTERNATE_POCSAG_LEDS)
   pinMode(PIN_POCSAG, OUTPUT);
 #endif
@@ -185,14 +188,13 @@ void CIO::startInt()
 void CIO::interrupt()
 {
   if ((ADC->ADC_ISR & ADC_ISR_EOC_Chan) == ADC_ISR_EOC_Chan) {    // Ensure there was an End-of-Conversion and we read the ISR reg
-    uint8_t control = MARK_NONE;
-    uint16_t sample = DC_OFFSET;
+    TSample sample = {DC_OFFSET, MARK_NONE};
 
-    m_txBuffer.get(sample, control);
-    DACC->DACC_CDR = sample;
+    m_txBuffer.get(sample);
+    DACC->DACC_CDR = sample.sample;
 
-    sample = ADC->ADC_CDR[ADC_CDR_Chan];
-    m_rxBuffer.put(sample, control);
+    sample.sample = ADC->ADC_CDR[ADC_CDR_Chan];
+    m_rxBuffer.put(sample);
 
 #if defined(SEND_RSSI_DATA)
     m_rssiBuffer.put(ADC->ADC_CDR[RSSI_CDR_Chan]);
@@ -254,6 +256,16 @@ void CIO::setNXDNInt(bool on)
 #endif
 }
 
+void CIO::setM17Int(bool on)
+{
+#if defined(USE_ALTERNATE_M17_LEDS)
+  digitalWrite(PIN_DSTAR, on ? HIGH : LOW);
+  digitalWrite(PIN_P25,   on ? HIGH : LOW);
+#else
+  digitalWrite(PIN_M17, on ? HIGH : LOW);
+#endif
+}
+
 void CIO::setPOCSAGInt(bool on)
 {
 #if defined(USE_ALTERNATE_POCSAG_LEDS)
@@ -279,4 +291,33 @@ void CIO::delayInt(unsigned int dly)
   delay(dly);
 }
 
+uint8_t CIO::getCPU() const
+{
+  return 0U;
+}
+
+// Code taken from https://github.com/emagii/at91sam3s/blob/master/examples/eefc_uniqueid/main.c
+void CIO::getUDID(uint8_t* buffer)
+{
+  uint32_t status;
+
+  EFC1->EEFC_FCR = (0x5A << 24) | EFC_FCMD_STUI;
+  do {
+    status = EFC1->EEFC_FSR;
+  } while ( (status & EEFC_FSR_FRDY) == EEFC_FSR_FRDY );
+
+  for (uint8_t i = 0; i < 16; i+=4) {
+    buffer[i + 0] = *(uint32_t *)(IFLASH1_ADDR + i) >> 24;
+    buffer[i + 1] = *(uint32_t *)(IFLASH1_ADDR + i) >> 16;
+    buffer[i + 2] = *(uint32_t *)(IFLASH1_ADDR + i) >>  8;
+    buffer[i + 3] = *(uint32_t *)(IFLASH1_ADDR + i) >>  0;
+  }
+
+  EFC1->EEFC_FCR = (0x5A << 24) | EFC_FCMD_SPUI;
+  do {
+    status = EFC1->EEFC_FSR;
+  } while ( (status & EEFC_FSR_FRDY) != EEFC_FSR_FRDY );
+}
+
 #endif
+

IOPins.h

@@ -59,12 +59,21 @@
 #elif defined(STM32F4_DVM)
     #include "pins/pins_f4_stm32dvm_v3.h"
 
+#elif defined(STM32F7_DVM)
+    #include "pins/pins_f7_stm32dvm_v5.h"
+
 #elif defined(DRCC_DVM_NQF)
     #include "pins/pins_f4_drcc_nqf.h"
 
+#elif defined(DRCC_DVM_HHP446)
+    #include "pins/pins_f4_drcc_hhp446.h"
+
+#elif defined(STM32F4_EDA_405) || defined(STM32F4_EDA_446)
+    #include "pins/pins_f4_stm32eda.h"
+
 #else
     #error "A valid board type macro need to be defined."
 
 #endif
 
-#endif  //#ifndef _IO_PINS_H
+#endif  //#ifndef _IO_PINS_H

IOSTM.cpp

@@ -106,6 +106,14 @@ void CIO::initInt()
    GPIO_Init(PORT_NXDN, &GPIO_InitStruct);
 #endif
 
+#if !defined(USE_ALTERNATE_M17_LEDS)
+   // M17 pin
+   RCC_AHB1PeriphClockCmd(RCC_Per_M17, ENABLE);
+   GPIO_InitStruct.GPIO_Pin   = PIN_M17;
+   GPIO_InitStruct.GPIO_Mode  = GPIO_Mode_OUT;
+   GPIO_Init(PORT_M17, &GPIO_InitStruct);
+#endif
+
 #if !defined(USE_ALTERNATE_POCSAG_LEDS)
    // POCSAG pin
    RCC_AHB1PeriphClockCmd(RCC_Per_POCSAG, ENABLE);
@@ -157,6 +165,14 @@ void CIO::initInt()
    GPIO_Init(PORT_MNXDN, &GPIO_InitStruct);
 #endif
 
+#if !defined(USE_ALTERNATE_M17_LEDS)
+   // M17 mode pin
+   RCC_AHB1PeriphClockCmd(RCC_Per_MM17, ENABLE);
+   GPIO_InitStruct.GPIO_Pin   = PIN_MM17;
+   GPIO_InitStruct.GPIO_Mode  = GPIO_Mode_OUT;
+   GPIO_Init(PORT_MM17, &GPIO_InitStruct);
+#endif
+
 #if !defined(USE_ALTERNATE_POCSAG_LEDS)
    // POCSAG mode pin
    RCC_AHB1PeriphClockCmd(RCC_Per_MPOCSAG, ENABLE);
@@ -326,25 +342,24 @@ void CIO::startInt()
 
 void CIO::interrupt()
 {
-   uint8_t control  = MARK_NONE;
-   uint16_t sample  = DC_OFFSET;
+   TSample sample = {DC_OFFSET, MARK_NONE};
    uint16_t rawRSSI = 0U;
 
-   m_txBuffer.get(sample, control);
+   m_txBuffer.get(sample);
 
    // Send the value to the DAC
 #if defined(STM32F4_NUCLEO) && defined(STM32F4_NUCLEO_ARDUINO_HEADER)
-   DAC_SetChannel2Data(DAC_Align_12b_R, sample);
+   DAC_SetChannel2Data(DAC_Align_12b_R, sample.sample);
 #else
-   DAC_SetChannel1Data(DAC_Align_12b_R, sample);
+   DAC_SetChannel1Data(DAC_Align_12b_R, sample.sample);
 #endif
 
    // Read value from ADC1 and ADC2
    if ((ADC_GetFlagStatus(ADC1, ADC_FLAG_EOC) == RESET)) {
       // shouldn't be still in reset at this point so null the sample value?
-      sample  = 0U;
+      sample.sample  = 0U;
    } else {
-      sample  = ADC_GetConversionValue(ADC1);
+      sample.sample  = ADC_GetConversionValue(ADC1);
 #if defined(SEND_RSSI_DATA)
       rawRSSI = ADC_GetConversionValue(ADC2);
 #endif
@@ -354,7 +369,7 @@ void CIO::interrupt()
    ADC_ClearFlag(ADC1, ADC_FLAG_EOC);
    ADC_SoftwareStartConv(ADC1);
 
-   m_rxBuffer.put(sample, control);
+   m_rxBuffer.put(sample);
    m_rssiBuffer.put(rawRSSI);
 
    m_watchdog++;
@@ -441,6 +456,27 @@ void CIO::setNXDNInt(bool on)
 #endif
 }
 
+void CIO::setM17Int(bool on)
+{
+#if defined(MODE_LEDS)
+#if defined(USE_ALTERNATE_M17_LEDS)
+   GPIO_WriteBit(PORT_DSTAR, PIN_DSTAR, on ? Bit_SET : Bit_RESET);
+   GPIO_WriteBit(PORT_P25,   PIN_P25, on ? Bit_SET : Bit_RESET);
+#else
+   GPIO_WriteBit(PORT_M17, PIN_M17, on ? Bit_SET : Bit_RESET);
+#endif
+#endif
+
+#if defined(MODE_PINS) && defined(STM32F4_NUCLEO_MORPHO_HEADER) && (defined(STM32F4_NUCLEO) || defined(STM32F722_RPT_HAT))
+#if defined(USE_ALTERNATE_M17_LEDS)
+   GPIO_WriteBit(PORT_MDSTAR, PIN_MDSTAR, on ? Bit_SET : Bit_RESET);
+   GPIO_WriteBit(PORT_MP25,   PIN_MP25,   on ? Bit_SET : Bit_RESET);
+#else
+   GPIO_WriteBit(PORT_MM17, PIN_MM17, on ? Bit_SET : Bit_RESET);
+#endif
+#endif
+}
+
 void CIO::setPOCSAGInt(bool on)
 {
 #if defined(MODE_LEDS)
@@ -509,4 +545,21 @@ void CIO::delayInt(unsigned int dly)
   }
 }
 
+uint8_t CIO::getCPU() const
+{
+  return 2U;
+}
+
+void CIO::getUDID(uint8_t* buffer)
+{
+#if defined(STM32F4XX)
+  ::memcpy(buffer, (void *)0x1FFF7A10, 12U);
+#elif defined(STM32F722xx)
+  ::memcpy(buffer, (void *)0x1FF07A10, 12U);
+#elif defined(STM32F767xx)
+  ::memcpy(buffer, (void *)0x1FF0F420, 12U);
 #endif
+}
+
+#endif
+

IOSTM_CMSIS.cpp

@@ -23,7 +23,6 @@
 #include "Globals.h"
 #include "IO.h"
 
-
 #if defined(STM32F1)
 
 #if defined(STM32F1_POG)
@@ -41,7 +40,6 @@ YSF      PB8    output
 P25      PB9    output
 NXDN     PB10   output
 POCSAG   PB11   output
-FM       PB12   output
 
 RX       PB0    analog input (ADC1_8)
 RSSI     PB1    analog input (ADC2_9)
@@ -85,9 +83,6 @@ USART1_RXD PA10  input (AF)
 #define PIN_POCSAG        11
 #define PORT_POCSAG       GPIOB
 #define BB_POCSAG         *((bitband_t)BITBAND_PERIPH(&PORT_POCSAG->ODR, PIN_POCSAG))
-#define PIN_FM            14
-#define PORT_FM           GPIOB
-#define BB_FM             *((bitband_t)BITBAND_PERIPH(&PORT_FM->ODR, PIN_FM))
 
 #define PIN_RX            0
 #define PIN_RX_ADC_CH     8
@@ -158,35 +153,16 @@ void GPIOConfigPin(GPIO_TypeDef *port_ptr, uint32_t pin, uint32_t mode_cnf_value
 #if defined(STM32F1_POG)
 void FancyLEDEffect()
 {
-  int ledCount = 10;
-
-  bitband_t foo[] = {&BB_LED, &BB_COSLED, &BB_PTT, &BB_DMR, &BB_DSTAR, &BB_YSF, &BB_P25,
-#if defined(USE_ALTERNATE_NXDN_LEDS)
-	NULL,
-#else
-	&BB_NXDN,
-#endif
-#if defined(USE_ALTERNATE_POCSAG_LEDS)
-	NULL,
-#else
-  	&BB_POCSAG,
-#endif
-#if defined(USE_ALTERNATE_FM_LEDS)
-	NULL};
-#else
-	&BB_FM};
-#endif
-
-  for(int i=0; i<ledCount; i++){
-    if(foo[i] != NULL)
-      *foo[i] = 0x01;
+  bitband_t foo[] = {&BB_LED, &BB_COSLED, &BB_PTT, &BB_DMR, &BB_DSTAR, &BB_YSF, &BB_P25};
+   
+  for(int i=0; i<7; i++){
+    *foo[i] = 0x01;
   }
   GPIOConfigPin(PORT_USART1_TXD, PIN_USART1_TXD, GPIO_CRL_MODE0_1);
   *((bitband_t)BITBAND_PERIPH(&PORT_USART1_TXD->ODR, PIN_USART1_TXD)) = 0x00;
   delay(SystemCoreClock/1000*100);
-  for(int i=0; i<ledCount; i++){
-    if(foo[i] != NULL)
-      *foo[i] = 0x00;
+  for(int i=0; i<7; i++){
+    *foo[i] = 0x00;
   }
   *((bitband_t)BITBAND_PERIPH(&PORT_USART1_TXD->ODR, PIN_USART1_TXD)) = 0x01;
   delay(SystemCoreClock/1000*20);
@@ -195,22 +171,18 @@ void FancyLEDEffect()
   *((bitband_t)BITBAND_PERIPH(&PORT_USART1_TXD->ODR, PIN_USART1_TXD)) = 0x01;
   
   *foo[0] = 0x01;
-  for(int i=1; i<ledCount; i++){
+  for(int i=1; i<7; i++){
     delay(SystemCoreClock/1000*10);
-    if (foo[i-1] != NULL)
-      *foo[i-1] = 0x00;
-    if (foo[i] != NULL)
-      *foo[i] = 0x01;
+    *foo[i-1] = 0x00;
+    *foo[i] = 0x01;
   }
-  for(int i=ledCount - 2; i>=0; i--) {
+  for(int i=5; i>=0; i--){
     delay(SystemCoreClock/1000*10);
-    if (foo[i+1] != NULL)
-      *foo[i+1] = 0x00;
-    if (foo[i] != NULL)
-      *foo[i] = 0x01;
+    *foo[i+1] = 0x00;
+    *foo[i] = 0x01;
   }
   delay(SystemCoreClock/1000*10);
-  *foo[0] = 0x00;
+  *foo[5+1-6] = 0x00;
   *((bitband_t)BITBAND_PERIPH(&PORT_USART1_TXD->ODR, PIN_USART1_TXD)) = 0x00;
   delay(SystemCoreClock/1000*10);
   *((bitband_t)BITBAND_PERIPH(&PORT_USART1_TXD->ODR, PIN_USART1_TXD)) = 0x01;
@@ -252,12 +224,12 @@ static inline void GPIOInit()
 #if !defined(USE_ALTERNATE_NXDN_LEDS)
   GPIOConfigPin(PORT_NXDN,   PIN_NXDN,   GPIO_CRL_MODE0_1);
 #endif
+#if !defined(USE_ALTERNATE_M17_LEDS)
+  GPIOConfigPin(PORT_M17,    PIN_M17,    GPIO_CRL_MODE0_1);
+#endif
 #if !defined(USE_ALTERNATE_POCSAG_LEDS)
   GPIOConfigPin(PORT_POCSAG, PIN_POCSAG, GPIO_CRL_MODE0_1);
 #endif
-#if !defined(USE_ALTERNATE_FM_LEDS)
-  GPIOConfigPin(PORT_FM,     PIN_FM,     GPIO_CRL_MODE0_1);
-#endif
 
   GPIOConfigPin(PORT_RX, PIN_RX, 0);
 #if defined(SEND_RSSI_DATA)
@@ -397,8 +369,7 @@ void CIO::startInt()
 
 void CIO::interrupt()
 {
-  uint8_t control  = MARK_NONE;
-  uint16_t sample  = DC_OFFSET;
+  TSample sample = {DC_OFFSET, MARK_NONE};
 #if defined(SEND_RSSI_DATA)
   uint16_t rawRSSI = 0U;
 #endif
@@ -415,12 +386,12 @@ void CIO::interrupt()
     *rssi_adon = 1;
 #endif
     
-    m_txBuffer.get(sample, control);
-    DAC->DHR12R1 = sample;  // Send the value to the DAC
+    m_txBuffer.get(sample);
+    DAC->DHR12R1 = sample.sample;  // Send the value to the DAC
 
     // Read value from ADC1 and ADC2
-    sample  = ADC1->DR;   // read conversion result; EOC is cleared by this read
-    m_rxBuffer.put(sample, control);
+    sample.sample  = ADC1->DR;   // read conversion result; EOC is cleared by this read
+    m_rxBuffer.put(sample);
 #if defined(SEND_RSSI_DATA)
     rawRSSI = ADC2->DR;
     m_rssiBuffer.put(rawRSSI);
@@ -480,6 +451,16 @@ void CIO::setNXDNInt(bool on)
 #endif
 }
 
+void CIO::setM17Int(bool on)
+{
+#if defined(USE_ALTERNATE_M17_LEDS)
+  BB_DSTAR = !!on;
+  BB_P25   = !!on;
+#else
+  BB_M17 = !!on;
+#endif
+}
+
 void CIO::setPOCSAGInt(bool on)
 {
 #if defined(USE_ALTERNATE_POCSAG_LEDS)
@@ -495,8 +476,6 @@ void CIO::setFMInt(bool on)
 #if defined(USE_ALTERNATE_FM_LEDS)
   BB_DSTAR = !!on;
   BB_YSF   = !!on;
-#else
-  BB_FM = !!on;
 #endif
 }
 
@@ -505,4 +484,17 @@ void CIO::delayInt(unsigned int dly)
   delay(dly);
 }
 
+uint8_t CIO::getCPU() const
+{
+  return 2U;
+}
+
+void CIO::getUDID(uint8_t* buffer)
+{
+#if defined(STM32F105xC)
+  ::memcpy(buffer, (void *)0x1FFFF7E8, 12U);
 #endif
+}
+
+#endif
+

IOTeensy.cpp

@@ -75,6 +75,9 @@ void CIO::initInt()
 #if !defined(USE_ALTERNATE_NXDN_LEDS)
   pinMode(PIN_NXDN,   OUTPUT);
 #endif
+#if !defined(USE_ALTERNATE_M17_LEDS)
+  pinMode(PIN_M17,    OUTPUT);
+#endif
 #if !defined(USE_ALTERNATE_POCSAG_LEDS)
   pinMode(PIN_POCSAG, OUTPUT);
 #endif
@@ -161,15 +164,14 @@ void CIO::startInt()
 
 void CIO::interrupt()
 {
-  uint8_t control = MARK_NONE;
-  uint16_t sample = DC_OFFSET;
+   TSample sample = {DC_OFFSET, MARK_NONE};
 
-  m_txBuffer.get(sample, control);
-  *(int16_t *)&(DAC0_DAT0L) = sample;
+  m_txBuffer.get(sample);
+  *(int16_t *)&(DAC0_DAT0L) = sample.sample;
 
   if ((ADC0_SC1A & ADC_SC1_COCO) == ADC_SC1_COCO) {
-    sample = ADC0_RA;
-    m_rxBuffer.put(sample, control);
+    sample.sample = ADC0_RA;
+    m_rxBuffer.put(sample);
   }
     
 #if defined(SEND_RSSI_DATA)
@@ -238,6 +240,16 @@ void CIO::setNXDNInt(bool on)
 #endif
 }
 
+void CIO::setM17Int(bool on)
+{
+#if defined(USE_ALTERNATE_M17_LEDS)
+  digitalWrite(PIN_DSTAR, on ? HIGH : LOW);
+  digitalWrite(PIN_P25,   on ? HIGH : LOW);
+#else
+  digitalWrite(PIN_M17, on ? HIGH : LOW);
+#endif
+}
+
 void CIO::setPOCSAGInt(bool on)
 {
 #if defined(USE_ALTERNATE_POCSAG_LEDS)
@@ -263,4 +275,15 @@ void CIO::delayInt(unsigned int dly)
   delay(dly);
 }
 
+uint8_t CIO::getCPU() const
+{
+  return 1U;
+}
+
+void CIO::getUDID(uint8_t* buffer)
+{
+  ::memcpy(buffer, (void *)0x4058, 16U);
+}
+
 #endif
+

M17Defines.h

@@ -0,0 +1,67 @@
+/*
+ *   Copyright (C) 2016,2017,2018,2020,2021 by Jonathan Naylor G4KLX
+ *
+ *   This program is free software; you can redistribute it and/or modify
+ *   it under the terms of the GNU General Public License as published by
+ *   the Free Software Foundation; either version 2 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ *
+ *   You should have received a copy of the GNU General Public License
+ *   along with this program; if not, write to the Free Software
+ *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#if !defined(M17DEFINES_H)
+#define  M17DEFINES_H
+
+const unsigned int M17_RADIO_SYMBOL_LENGTH = 5U;      // At 24 kHz sample rate
+
+const unsigned int M17_FRAME_LENGTH_BITS    = 384U;
+const unsigned int M17_FRAME_LENGTH_BYTES   = M17_FRAME_LENGTH_BITS / 8U;
+const unsigned int M17_FRAME_LENGTH_SYMBOLS = M17_FRAME_LENGTH_BITS / 2U;
+const unsigned int M17_FRAME_LENGTH_SAMPLES = M17_FRAME_LENGTH_SYMBOLS * M17_RADIO_SYMBOL_LENGTH;
+
+const unsigned int M17_SYNC_LENGTH_BITS    = 16U;
+const unsigned int M17_SYNC_LENGTH_BYTES   = M17_SYNC_LENGTH_BITS / 8U;
+const unsigned int M17_SYNC_LENGTH_SYMBOLS = M17_SYNC_LENGTH_BITS / 2U;
+const unsigned int M17_SYNC_LENGTH_SAMPLES = M17_SYNC_LENGTH_SYMBOLS * M17_RADIO_SYMBOL_LENGTH;
+
+const uint8_t M17_LINK_SETUP_SYNC_BYTES[] = {0x55U, 0xF7U};
+const uint8_t M17_STREAM_SYNC_BYTES[]     = {0xFFU, 0x5DU};
+const uint8_t M17_EOF_SYNC_BYTES[]        = {0x55U, 0x5DU};
+
+const uint16_t M17_LINK_SETUP_SYNC_BITS = 0x55F7U;
+const uint16_t M17_STREAM_SYNC_BITS     = 0xFF5DU;
+const uint16_t M17_EOF_SYNC_BITS        = 0x555DU;
+
+// 5     5     F     7
+// 01 01 01 01 11 11 01 11
+// +3 +3 +3 +3 -3 -3 +3 -3
+
+const int8_t M17_LINK_SETUP_SYNC_SYMBOLS_VALUES[] = {+3, +3, +3, +3, -3, -3, +3, -3};
+
+const uint8_t M17_LINK_SETUP_SYNC_SYMBOLS = 0xF2U;
+
+// F     F     5     D
+// 11 11 11 11 01 01 11 01
+// -3 -3 -3 -3 +3 +3 -3 +3
+
+const int8_t M17_STREAM_SYNC_SYMBOLS_VALUES[] = {-3, -3, -3, -3, +3, +3, -3, +3};
+
+const uint8_t M17_STREAM_SYNC_SYMBOLS = 0x0DU;
+
+// 5     5     5     D
+// 01 01 01 01 01 01 11 01
+// +3 +3 +3 +3 +3 +3 -3 +3
+
+const int8_t M17_EOF_SYNC_SYMBOLS_VALUES[] = {+3, +3, +3, +3, +3, +3, -3, +3};
+
+const uint8_t M17_EOF_SYNC_SYMBOLS = 0xFDU;
+
+#endif
+

M17RX.cpp

@@ -0,0 +1,485 @@
+/*
+ *   Copyright (C) 2009-2017,2020,2021 by Jonathan Naylor G4KLX
+ *
+ *   This program is free software; you can redistribute it and/or modify
+ *   it under the terms of the GNU General Public License as published by
+ *   the Free Software Foundation; either version 2 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ *
+ *   You should have received a copy of the GNU General Public License
+ *   along with this program; if not, write to the Free Software
+ *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include "Config.h"
+
+#if defined(MODE_M17)
+
+#include "Globals.h"
+#include "M17RX.h"
+#include "Utils.h"
+
+const q15_t SCALING_FACTOR = 18750;      // Q15(0.55)
+
+const uint8_t MAX_SYNC_BIT_START_ERRS = 0U;
+const uint8_t MAX_SYNC_BIT_RUN_ERRS   = 2U;
+
+const uint8_t MAX_SYNC_SYMBOL_START_ERRS = 0U;
+const uint8_t MAX_SYNC_SYMBOL_RUN_ERRS   = 1U;
+
+const uint8_t BIT_MASK_TABLE[] = {0x80U, 0x40U, 0x20U, 0x10U, 0x08U, 0x04U, 0x02U, 0x01U};
+
+#define WRITE_BIT1(p,i,b) p[(i)>>3] = (b) ? (p[(i)>>3] | BIT_MASK_TABLE[(i)&7]) : (p[(i)>>3] & ~BIT_MASK_TABLE[(i)&7])
+
+const uint8_t NOAVEPTR = 99U;
+
+const uint16_t NOENDPTR = 9999U;
+
+const unsigned int MAX_SYNC_FRAMES = 3U + 1U;
+
+CM17RX::CM17RX() :
+m_state(M17RXS_NONE),
+m_bitBuffer(),
+m_buffer(),
+m_bitPtr(0U),
+m_dataPtr(0U),
+m_startPtr(NOENDPTR),
+m_endPtr(NOENDPTR),
+m_syncPtr(NOENDPTR),
+m_minSyncPtr(NOENDPTR),
+m_maxSyncPtr(NOENDPTR),
+m_maxCorr(0),
+m_lostCount(0U),
+m_countdown(0U),
+m_nextState(M17RXS_NONE),
+m_centre(),
+m_centreVal(0),
+m_threshold(),
+m_thresholdVal(0),
+m_averagePtr(NOAVEPTR),
+m_rssiAccum(0U),
+m_rssiCount(0U)
+{
+}
+
+void CM17RX::reset()
+{
+  m_state        = M17RXS_NONE;
+  m_dataPtr      = 0U;
+  m_bitPtr       = 0U;
+  m_maxCorr      = 0;
+  m_averagePtr   = NOAVEPTR;
+  m_startPtr     = NOENDPTR;
+  m_endPtr       = NOENDPTR;
+  m_syncPtr      = NOENDPTR;
+  m_minSyncPtr   = NOENDPTR;
+  m_maxSyncPtr   = NOENDPTR;
+  m_centreVal    = 0;
+  m_thresholdVal = 0;
+  m_lostCount    = 0U;
+  m_countdown    = 0U;
+  m_nextState    = M17RXS_NONE;
+  m_rssiAccum    = 0U;
+  m_rssiCount    = 0U;
+}
+
+void CM17RX::samples(const q15_t* samples, uint16_t* rssi, uint8_t length)
+{
+  for (uint8_t i = 0U; i < length; i++) {
+    q15_t sample = samples[i];
+
+    m_rssiAccum += rssi[i];
+    m_rssiCount++;
+
+    m_bitBuffer[m_bitPtr] <<= 1;
+    if (sample < 0)
+      m_bitBuffer[m_bitPtr] |= 0x01U;
+
+    m_buffer[m_dataPtr] = sample;
+
+    switch (m_state) {
+    case M17RXS_LINK_SETUP:
+    case M17RXS_STREAM:
+      processData(sample);
+      break;
+    default:
+      processNone(sample);
+      break;
+    }
+
+    m_dataPtr++;
+    if (m_dataPtr >= M17_FRAME_LENGTH_SAMPLES)
+      m_dataPtr = 0U;
+
+    m_bitPtr++;
+    if (m_bitPtr >= M17_RADIO_SYMBOL_LENGTH)
+      m_bitPtr = 0U;
+  }
+}
+
+void CM17RX::processNone(q15_t sample)
+{
+  bool ret1 = correlateSync(M17_LINK_SETUP_SYNC_SYMBOLS, M17_LINK_SETUP_SYNC_SYMBOLS_VALUES, M17_LINK_SETUP_SYNC_BYTES, MAX_SYNC_SYMBOL_START_ERRS, MAX_SYNC_BIT_START_ERRS);
+  bool ret2 = correlateSync(M17_STREAM_SYNC_SYMBOLS,     M17_STREAM_SYNC_SYMBOLS_VALUES,     M17_STREAM_SYNC_BYTES,     MAX_SYNC_SYMBOL_START_ERRS, MAX_SYNC_BIT_START_ERRS);
+
+  if (ret1 || ret2) {
+    // On the first sync, start the countdown to the state change
+    if (m_countdown == 0U) {
+      m_rssiAccum = 0U;
+      m_rssiCount = 0U;
+
+      io.setDecode(true);
+      io.setADCDetection(true);
+
+      m_averagePtr = NOAVEPTR;
+
+      m_countdown = 5U;
+      
+      if (ret1) m_nextState = M17RXS_LINK_SETUP;
+      if (ret2) m_nextState = M17RXS_STREAM;
+    }
+  }
+
+  if (m_countdown > 0U)
+    m_countdown--;
+
+  if (m_countdown == 1U) {
+    m_minSyncPtr = m_syncPtr + M17_FRAME_LENGTH_SAMPLES - 1U;
+    if (m_minSyncPtr >= M17_FRAME_LENGTH_SAMPLES)
+      m_minSyncPtr -= M17_FRAME_LENGTH_SAMPLES;
+
+    m_maxSyncPtr = m_syncPtr + 1U;
+    if (m_maxSyncPtr >= M17_FRAME_LENGTH_SAMPLES)
+      m_maxSyncPtr -= M17_FRAME_LENGTH_SAMPLES;
+
+    m_state     = m_nextState;
+    m_countdown = 0U;
+    m_nextState = M17RXS_NONE;
+  }
+}
+
+void CM17RX::processData(q15_t sample)
+{
+  bool eof = false;
+
+  if (m_minSyncPtr < m_maxSyncPtr) {
+    if (m_dataPtr >= m_minSyncPtr && m_dataPtr <= m_maxSyncPtr) {
+      bool ret = correlateSync(M17_STREAM_SYNC_SYMBOLS, M17_STREAM_SYNC_SYMBOLS_VALUES, M17_STREAM_SYNC_BYTES,  MAX_SYNC_SYMBOL_RUN_ERRS, MAX_SYNC_BIT_RUN_ERRS);
+
+      eof = correlateSync(M17_EOF_SYNC_SYMBOLS, M17_EOF_SYNC_SYMBOLS_VALUES, M17_EOF_SYNC_BYTES, MAX_SYNC_SYMBOL_RUN_ERRS, MAX_SYNC_BIT_RUN_ERRS);
+
+      if (ret) m_state = M17RXS_STREAM;
+    }
+  } else {
+    if (m_dataPtr >= m_minSyncPtr || m_dataPtr <= m_maxSyncPtr) {
+      bool ret = correlateSync(M17_STREAM_SYNC_SYMBOLS, M17_STREAM_SYNC_SYMBOLS_VALUES, M17_STREAM_SYNC_BYTES,  MAX_SYNC_SYMBOL_RUN_ERRS, MAX_SYNC_BIT_RUN_ERRS);
+
+      eof = correlateSync(M17_EOF_SYNC_SYMBOLS, M17_EOF_SYNC_SYMBOLS_VALUES, M17_EOF_SYNC_BYTES, MAX_SYNC_SYMBOL_RUN_ERRS, MAX_SYNC_BIT_RUN_ERRS);
+
+      if (ret) m_state = M17RXS_STREAM;
+    }
+  }
+
+  if (eof) {
+    DEBUG4("M17RX: eof sync found pos/centre/threshold", m_syncPtr, m_centreVal, m_thresholdVal);
+
+    io.setDecode(false);
+    io.setADCDetection(false);
+
+    serial.writeM17EOT();
+
+    m_state      = M17RXS_NONE;
+    m_endPtr     = NOENDPTR;
+    m_averagePtr = NOAVEPTR;
+    m_countdown  = 0U;
+    m_nextState  = M17RXS_NONE;
+    m_maxCorr    = 0;
+  }
+
+  if (m_dataPtr == m_endPtr) {
+    // Only update the centre and threshold if they are from a good sync
+    if (m_lostCount == MAX_SYNC_FRAMES) {
+      m_minSyncPtr = m_syncPtr + M17_FRAME_LENGTH_SAMPLES - 1U;
+      if (m_minSyncPtr >= M17_FRAME_LENGTH_SAMPLES)
+        m_minSyncPtr -= M17_FRAME_LENGTH_SAMPLES;
+
+      m_maxSyncPtr = m_syncPtr + 1U;
+      if (m_maxSyncPtr >= M17_FRAME_LENGTH_SAMPLES)
+        m_maxSyncPtr -= M17_FRAME_LENGTH_SAMPLES;
+    }
+
+    calculateLevels(m_startPtr, M17_FRAME_LENGTH_SYMBOLS);
+
+    switch (m_state) {
+      case M17RXS_LINK_SETUP:
+        DEBUG4("M17RX: link setup sync found pos/centre/threshold", m_syncPtr, m_centreVal, m_thresholdVal);
+        break;
+      case M17RXS_STREAM:
+        DEBUG4("M17RX: stream sync found pos/centre/threshold", m_syncPtr, m_centreVal, m_thresholdVal);
+        break;
+      default:
+        break;  
+    }
+
+    uint8_t frame[M17_FRAME_LENGTH_BYTES + 3U];
+    samplesToBits(m_startPtr, M17_FRAME_LENGTH_SYMBOLS, frame, 8U, m_centreVal, m_thresholdVal);
+
+    // We've not seen a stream sync for too long, signal RXLOST and change to RX_NONE
+    m_lostCount--;
+    if (m_lostCount == 0U) {
+      DEBUG1("M17RX: sync timed out, lost lock");
+
+      io.setDecode(false);
+      io.setADCDetection(false);
+
+      serial.writeM17Lost();
+
+      m_state      = M17RXS_NONE;
+      m_endPtr     = NOENDPTR;
+      m_averagePtr = NOAVEPTR;
+      m_countdown  = 0U;
+      m_nextState  = M17RXS_NONE;
+      m_maxCorr    = 0;
+    } else {
+      frame[0U] = m_lostCount == (MAX_SYNC_FRAMES - 1U) ? 0x01U : 0x00U;
+
+      switch (m_state) {
+        case M17RXS_LINK_SETUP:
+          writeRSSILinkSetup(frame);
+          break;
+        case M17RXS_STREAM:
+          writeRSSIStream(frame);
+          break;
+        default:
+          break;  
+      }
+
+      m_maxCorr   = 0;
+      m_nextState = M17RXS_NONE;
+    }
+  }
+}
+
+bool CM17RX::correlateSync(uint8_t syncSymbols, const int8_t* syncSymbolValues, const uint8_t* syncBytes, uint8_t maxSymbolErrs, uint8_t maxBitErrs)
+{
+  if (countBits8(m_bitBuffer[m_bitPtr] ^ syncSymbols) <= maxSymbolErrs) {
+    uint16_t ptr = m_dataPtr + M17_FRAME_LENGTH_SAMPLES - M17_SYNC_LENGTH_SAMPLES + M17_RADIO_SYMBOL_LENGTH;
+    if (ptr >= M17_FRAME_LENGTH_SAMPLES)
+      ptr -= M17_FRAME_LENGTH_SAMPLES;
+
+    q31_t corr = 0;
+    q15_t min =  16000;
+    q15_t max = -16000;
+
+    for (uint8_t i = 0U; i < M17_SYNC_LENGTH_SYMBOLS; i++) {
+      q15_t val = m_buffer[ptr];
+
+      if (val > max)
+        max = val;
+      if (val < min)
+        min = val;
+
+      switch (syncSymbolValues[i]) {
+      case +3:
+        corr -= (val + val + val);
+        break;
+      case +1:
+        corr -= val;
+        break;
+      case -1:
+        corr += val;
+        break;
+      default:  // -3
+        corr += (val + val + val);
+        break;
+      }
+
+      ptr += M17_RADIO_SYMBOL_LENGTH;
+      if (ptr >= M17_FRAME_LENGTH_SAMPLES)
+        ptr -= M17_FRAME_LENGTH_SAMPLES;
+    }
+
+    if (corr > m_maxCorr) {
+      if (m_averagePtr == NOAVEPTR) {
+        m_centreVal = (max + min) >> 1;
+
+        q31_t v1 = (max - m_centreVal) * SCALING_FACTOR;
+        m_thresholdVal = q15_t(v1 >> 15);
+      }
+
+      uint16_t startPtr = m_dataPtr + M17_FRAME_LENGTH_SAMPLES - M17_SYNC_LENGTH_SAMPLES + M17_RADIO_SYMBOL_LENGTH;
+      if (startPtr >= M17_FRAME_LENGTH_SAMPLES)
+        startPtr -= M17_FRAME_LENGTH_SAMPLES;
+
+      uint8_t sync[M17_SYNC_LENGTH_BYTES];
+      samplesToBits(startPtr, M17_SYNC_LENGTH_SYMBOLS, sync, 0U, m_centreVal, m_thresholdVal);
+
+      uint8_t errs = 0U;
+      for (uint8_t i = 0U; i < M17_SYNC_LENGTH_BYTES; i++)
+        errs += countBits8(sync[i] ^ syncBytes[i]);
+
+      if (errs <= maxBitErrs) {
+        m_maxCorr   = corr;
+        m_lostCount = MAX_SYNC_FRAMES;
+        m_syncPtr   = m_dataPtr;
+
+        m_startPtr = startPtr;
+
+        m_endPtr = m_dataPtr + M17_FRAME_LENGTH_SAMPLES - M17_SYNC_LENGTH_SAMPLES - 1U;
+        if (m_endPtr >= M17_FRAME_LENGTH_SAMPLES)
+          m_endPtr -= M17_FRAME_LENGTH_SAMPLES;
+
+        return true;
+      }
+    }
+  }
+
+  return false;
+}
+
+void CM17RX::calculateLevels(uint16_t start, uint16_t count)
+{
+  q15_t maxPos = -16000;
+  q15_t minPos =  16000;
+  q15_t maxNeg =  16000;
+  q15_t minNeg = -16000;
+
+  for (uint16_t i = 0U; i < count; i++) {
+    q15_t sample = m_buffer[start];
+
+    if (sample > 0) {
+      if (sample > maxPos)
+        maxPos = sample;
+      if (sample < minPos)
+        minPos = sample;
+    } else {
+      if (sample < maxNeg)
+        maxNeg = sample;
+      if (sample > minNeg)
+        minNeg = sample;
+    }
+
+    start += M17_RADIO_SYMBOL_LENGTH;
+    if (start >= M17_FRAME_LENGTH_SAMPLES)
+      start -= M17_FRAME_LENGTH_SAMPLES;
+  }
+
+  q15_t posThresh = (maxPos + minPos) >> 1;
+  q15_t negThresh = (maxNeg + minNeg) >> 1;
+
+  q15_t centre = (posThresh + negThresh) >> 1;
+
+  q15_t threshold = posThresh - centre;
+
+  DEBUG5("M17RX: pos/neg/centre/threshold", posThresh, negThresh, centre, threshold);
+
+  if (m_averagePtr == NOAVEPTR) {
+    for (uint8_t i = 0U; i < 16U; i++) {
+      m_centre[i] = centre;
+      m_threshold[i] = threshold;
+    }
+
+    m_averagePtr = 0U;
+  } else {
+    m_centre[m_averagePtr] = centre;
+    m_threshold[m_averagePtr] = threshold;
+
+    m_averagePtr++;
+    if (m_averagePtr >= 16U)
+      m_averagePtr = 0U;
+  }
+
+  m_centreVal = 0;
+  m_thresholdVal = 0;
+
+  for (uint8_t i = 0U; i < 16U; i++) {
+    m_centreVal += m_centre[i];
+    m_thresholdVal += m_threshold[i];
+  }
+
+  m_centreVal >>= 4;
+  m_thresholdVal >>= 4;
+}
+
+void CM17RX::samplesToBits(uint16_t start, uint16_t count, uint8_t* buffer, uint16_t offset, q15_t centre, q15_t threshold)
+{
+  for (uint16_t i = 0U; i < count; i++) {
+    q15_t sample = m_buffer[start] - centre;
+
+    if (sample < -threshold) {
+      WRITE_BIT1(buffer, offset, false);
+      offset++;
+      WRITE_BIT1(buffer, offset, true);
+      offset++;
+    } else if (sample < 0) {
+      WRITE_BIT1(buffer, offset, false);
+      offset++;
+      WRITE_BIT1(buffer, offset, false);
+      offset++;
+    } else if (sample < threshold) {
+      WRITE_BIT1(buffer, offset, true);
+      offset++;
+      WRITE_BIT1(buffer, offset, false);
+      offset++;
+    } else {
+      WRITE_BIT1(buffer, offset, true);
+      offset++;
+      WRITE_BIT1(buffer, offset, true);
+      offset++;
+    }
+
+    start += M17_RADIO_SYMBOL_LENGTH;
+    if (start >= M17_FRAME_LENGTH_SAMPLES)
+      start -= M17_FRAME_LENGTH_SAMPLES;
+  }
+}
+
+void CM17RX::writeRSSILinkSetup(uint8_t* data)
+{
+#if defined(SEND_RSSI_DATA)
+  if (m_rssiCount > 0U) {
+    uint16_t rssi = m_rssiAccum / m_rssiCount;
+
+    data[49U] = (rssi >> 8) & 0xFFU;
+    data[50U] = (rssi >> 0) & 0xFFU;
+
+    serial.writeM17LinkSetup(data, M17_FRAME_LENGTH_BYTES + 3U);
+  } else {
+    serial.writeM17LinkSetup(data, M17_FRAME_LENGTH_BYTES + 1U);
+  }
+#else
+  serial.writeM17LinkSetup(data, M17_FRAME_LENGTH_BYTES + 1U);
+#endif
+
+  m_rssiAccum = 0U;
+  m_rssiCount = 0U;
+}
+
+void CM17RX::writeRSSIStream(uint8_t* data)
+{
+#if defined(SEND_RSSI_DATA)
+  if (m_rssiCount > 0U) {
+    uint16_t rssi = m_rssiAccum / m_rssiCount;
+
+    data[49U] = (rssi >> 8) & 0xFFU;
+    data[50U] = (rssi >> 0) & 0xFFU;
+
+    serial.writeM17Stream(data, M17_FRAME_LENGTH_BYTES + 3U);
+  } else {
+    serial.writeM17Stream(data, M17_FRAME_LENGTH_BYTES + 1U);
+  }
+#else
+  serial.writeM17Stream(data, M17_FRAME_LENGTH_BYTES + 1U);
+#endif
+
+  m_rssiAccum = 0U;
+  m_rssiCount = 0U;
+}
+
+#endif
+

M17RX.h

@@ -0,0 +1,77 @@
+/*
+ *   Copyright (C) 2015,2016,2017,2020,2021 by Jonathan Naylor G4KLX
+ *
+ *   This program is free software; you can redistribute it and/or modify
+ *   it under the terms of the GNU General Public License as published by
+ *   the Free Software Foundation; either version 2 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ *
+ *   You should have received a copy of the GNU General Public License
+ *   along with this program; if not, write to the Free Software
+ *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include "Config.h"
+
+#if defined(MODE_M17)
+
+#if !defined(M17RX_H)
+#define  M17RX_H
+
+#include "M17Defines.h"
+
+enum M17RX_STATE {
+  M17RXS_NONE,
+  M17RXS_LINK_SETUP,
+  M17RXS_STREAM
+};
+
+class CM17RX {
+public:
+  CM17RX();
+
+  void samples(const q15_t* samples, uint16_t* rssi, uint8_t length);
+
+  void reset();
+
+private:
+  M17RX_STATE m_state;
+  uint8_t     m_bitBuffer[M17_RADIO_SYMBOL_LENGTH];
+  q15_t       m_buffer[M17_FRAME_LENGTH_SAMPLES];
+  uint16_t    m_bitPtr;
+  uint16_t    m_dataPtr;
+  uint16_t    m_startPtr;
+  uint16_t    m_endPtr;
+  uint16_t    m_syncPtr;
+  uint16_t    m_minSyncPtr;
+  uint16_t    m_maxSyncPtr;
+  q31_t       m_maxCorr;
+  uint16_t    m_lostCount;
+  uint8_t     m_countdown;
+  M17RX_STATE m_nextState;
+  q15_t       m_centre[16U];
+  q15_t       m_centreVal;
+  q15_t       m_threshold[16U];
+  q15_t       m_thresholdVal;
+  uint8_t     m_averagePtr;
+  uint32_t    m_rssiAccum;
+  uint16_t    m_rssiCount;
+
+  void processNone(q15_t sample);
+  void processData(q15_t sample);
+  bool correlateSync(uint8_t syncSymbols, const int8_t* syncSymbolValues, const uint8_t* syncBytes, uint8_t maxSymbolErrs, uint8_t maxBitErrs);
+  void calculateLevels(uint16_t start, uint16_t count);
+  void samplesToBits(uint16_t start, uint16_t count, uint8_t* buffer, uint16_t offset, q15_t centre, q15_t threshold);
+  void writeRSSILinkSetup(uint8_t* data);
+  void writeRSSIStream(uint8_t* data);
+};
+
+#endif
+
+#endif
+

M17TX.cpp

@@ -0,0 +1,190 @@
+/*
+ *   Copyright (C) 2009-2018,2020,2021 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2017 by Andy Uribe CA6JAU
+ *
+ *   This program is free software; you can redistribute it and/or modify
+ *   it under the terms of the GNU General Public License as published by
+ *   the Free Software Foundation; either version 2 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ *
+ *   You should have received a copy of the GNU General Public License
+ *   along with this program; if not, write to the Free Software
+ *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include "Config.h"
+
+#if defined(MODE_M17)
+
+#include "Globals.h"
+#include "M17TX.h"
+
+#include "M17Defines.h"
+
+// Generated using rcosdesign(0.5, 8, 5, 'sqrt') in MATLAB
+static q15_t RRC_0_5_FILTER[] = {0, 0, 0, 0, -290, -174, 142, 432, 438, 90, -387, -561, -155, 658, 1225, 767,
+				  -980, -3326, -4648, -3062, 2527, 11552, 21705, 29724, 32767, 29724, 21705,
+				  11552, 2527, -3062, -4648, -3326, -980, 767, 1225, 658, -155, -561, -387, 90,
+				  438, 432, 142, -174, -290}; // numTaps = 45, L = 5
+const uint16_t RRC_0_5_FILTER_PHASE_LEN = 9U; // phaseLength = numTaps/L
+
+const q15_t M17_LEVELA =  1481;
+const q15_t M17_LEVELB =  494;
+const q15_t M17_LEVELC = -494;
+const q15_t M17_LEVELD = -1481;
+
+const uint8_t M17_START_SYNC = 0x77U;
+const uint8_t M17_END_SYNC   = 0xFFU;
+const uint8_t M17_HANG       = 0x00U;
+
+CM17TX::CM17TX() :
+m_buffer(TX_BUFFER_LEN),
+m_modFilter(),
+m_modState(),
+m_poBuffer(),
+m_poLen(0U),
+m_poPtr(0U),
+m_txDelay(240U),      // 200ms
+m_txHang(4800U),      // 4s
+m_txCount(0U)
+{
+  ::memset(m_modState, 0x00U, 16U * sizeof(q15_t));
+
+  m_modFilter.L           = M17_RADIO_SYMBOL_LENGTH;
+  m_modFilter.phaseLength = RRC_0_5_FILTER_PHASE_LEN;
+  m_modFilter.pCoeffs     = RRC_0_5_FILTER;
+  m_modFilter.pState      = m_modState;
+}
+
+void CM17TX::process()
+{
+  // If we have M17 data to transmit, do so.
+  if (m_poLen == 0U && m_buffer.getData() > 0U) {
+    if (!m_tx) {
+      for (uint16_t i = 0U; i < m_txDelay; i++)
+        m_poBuffer[m_poLen++] = M17_START_SYNC;
+    } else {
+      for (uint8_t i = 0U; i < M17_FRAME_LENGTH_BYTES; i++) {
+        uint8_t c = 0U;
+        m_buffer.get(c);
+        m_poBuffer[m_poLen++] = c;
+      }
+    }
+
+    m_poPtr = 0U;
+  }
+
+  if (m_poLen > 0U) {
+    // Transmit M17 data.
+    uint16_t space = io.getSpace();
+
+    while (space > (4U * M17_RADIO_SYMBOL_LENGTH)) {
+      uint8_t c = m_poBuffer[m_poPtr++];
+      writeByte(c);
+
+      // Reduce space and reset the hang timer.
+      space -= 4U * M17_RADIO_SYMBOL_LENGTH;
+      if (m_duplex)
+        m_txCount = m_txHang;
+
+      if (m_poPtr >= m_poLen) {
+        m_poPtr = 0U;
+        m_poLen = 0U;
+        return;
+      }
+    }
+  } else if (m_txCount > 0U) {
+    // Transmit silence until the hang timer has expired.
+    uint16_t space = io.getSpace();
+
+    while (space > (4U * M17_RADIO_SYMBOL_LENGTH)) {
+      writeSilence();
+
+      space -= 4U * M17_RADIO_SYMBOL_LENGTH;
+      m_txCount--;
+
+      if (m_txCount == 0U)
+        return;
+    }
+  }
+}
+
+uint8_t CM17TX::writeData(const uint8_t* data, uint8_t length)
+{
+  if (length != (M17_FRAME_LENGTH_BYTES + 1U))
+    return 4U;
+
+  uint16_t space = m_buffer.getSpace();
+  if (space < M17_FRAME_LENGTH_BYTES)
+    return 5U;
+
+  for (uint8_t i = 0U; i < M17_FRAME_LENGTH_BYTES; i++)
+    m_buffer.put(data[i + 1U]);
+
+  return 0U;
+}
+
+void CM17TX::writeByte(uint8_t c)
+{
+  q15_t inBuffer[4U];
+  q15_t outBuffer[M17_RADIO_SYMBOL_LENGTH * 4U];
+
+  const uint8_t MASK = 0xC0U;
+
+  for (uint8_t i = 0U; i < 4U; i++, c <<= 2) {
+    switch (c & MASK) {
+      case 0xC0U:
+        inBuffer[i] = M17_LEVELA;
+        break;
+      case 0x80U:
+        inBuffer[i] = M17_LEVELB;
+        break;
+      case 0x00U:
+        inBuffer[i] = M17_LEVELC;
+        break;
+      default:
+        inBuffer[i] = M17_LEVELD;
+        break;
+    }
+  }
+
+  ::arm_fir_interpolate_q15(&m_modFilter, inBuffer, outBuffer, 4U);
+
+  io.write(STATE_M17, outBuffer, M17_RADIO_SYMBOL_LENGTH * 4U);
+}
+
+void CM17TX::writeSilence()
+{
+  q15_t inBuffer[4U] = {0x00U, 0x00U, 0x00U, 0x00U};
+  q15_t outBuffer[M17_RADIO_SYMBOL_LENGTH * 4U];
+
+  ::arm_fir_interpolate_q15(&m_modFilter, inBuffer, outBuffer, 4U);
+
+  io.write(STATE_M17, outBuffer, M17_RADIO_SYMBOL_LENGTH * 4U);
+}
+
+void CM17TX::setTXDelay(uint8_t delay)
+{
+  m_txDelay = 600U + uint16_t(delay) * 12U;        // 500ms + tx delay
+
+  if (m_txDelay > 1200U)
+    m_txDelay = 1200U;
+}
+
+uint8_t CM17TX::getSpace() const
+{
+  return m_buffer.getSpace() / M17_FRAME_LENGTH_BYTES;
+}
+
+void CM17TX::setParams(uint8_t txHang)
+{
+  m_txHang = txHang * 1200U;
+}
+
+#endif
+

M17TX.h

@@ -0,0 +1,60 @@
+/*
+ *   Copyright (C) 2015,2016,2017,2020 by Jonathan Naylor G4KLX
+ *
+ *   This program is free software; you can redistribute it and/or modify
+ *   it under the terms of the GNU General Public License as published by
+ *   the Free Software Foundation; either version 2 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ *
+ *   You should have received a copy of the GNU General Public License
+ *   along with this program; if not, write to the Free Software
+ *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include "Config.h"
+
+#if defined(MODE_M17)
+
+#if !defined(M17TX_H)
+#define  M17TX_H
+
+#include "RingBuffer.h"
+
+class CM17TX {
+public:
+  CM17TX();
+
+  uint8_t writeData(const uint8_t* data, uint8_t length);
+
+  void process();
+
+  void setTXDelay(uint8_t delay);
+
+  uint8_t getSpace() const;
+
+  void setParams(uint8_t txHang);
+
+private:
+  CRingBuffer<uint8_t>             m_buffer;
+  arm_fir_interpolate_instance_q15 m_modFilter;
+  q15_t                            m_modState[16U];    // blockSize + phaseLength - 1, 4 + 9 - 1 plus some spare
+  uint8_t                          m_poBuffer[1200U];
+  uint16_t                         m_poLen;
+  uint16_t                         m_poPtr;
+  uint16_t                         m_txDelay;
+  uint32_t                         m_txHang;
+  uint32_t                         m_txCount;
+
+  void writeByte(uint8_t c);
+  void writeSilence();
+};
+
+#endif
+
+#endif
+

MMDVM.cpp

@@ -31,45 +31,75 @@ bool m_dmrEnable    = true;
 bool m_ysfEnable    = true;
 bool m_p25Enable    = true;
 bool m_nxdnEnable   = true;
+bool m_m17Enable    = true;
 bool m_pocsagEnable = true;
 bool m_fmEnable     = true;
+bool m_ax25Enable   = true;
 
 bool m_duplex = true;
 
 bool m_tx  = false;
 bool m_dcd = false;
 
-CDStarRX   dstarRX;
-CDStarTX   dstarTX;
-
-CDMRIdleRX dmrIdleRX;
-CDMRRX     dmrRX;
-CDMRTX     dmrTX;
-
-CDMRDMORX  dmrDMORX;
-CDMRDMOTX  dmrDMOTX;
-
-CYSFRX     ysfRX;
-CYSFTX     ysfTX;
-
-CP25RX     p25RX;
-CP25TX     p25TX;
-
-CNXDNRX    nxdnRX;
-CNXDNTX    nxdnTX;
-
-CPOCSAGTX  pocsagTX;
-
-CFM        fm;
+#if defined(MODE_DSTAR)
+CDStarRX dstarRX;
+CDStarTX dstarTX;
 
 CCalDStarRX calDStarRX;
 CCalDStarTX calDStarTX;
-CCalDMR     calDMR;
-CCalP25     calP25;
-CCalNXDN    calNXDN;
-CCalFM      calFM;
-CCalPOCSAG  calPOCSAG;
-CCalRSSI    calRSSI;
+#endif
+
+#if defined(MODE_DMR)
+CDMRIdleRX dmrIdleRX;
+CDMRRX dmrRX;
+CDMRTX dmrTX;
+
+CDMRDMORX dmrDMORX;
+CDMRDMOTX dmrDMOTX;
+
+CCalDMR calDMR;
+#endif
+
+#if defined(MODE_YSF)
+CYSFRX ysfRX;
+CYSFTX ysfTX;
+#endif
+
+#if defined(MODE_P25)
+CP25RX p25RX;
+CP25TX p25TX;
+
+CCalP25 calP25;
+#endif
+
+#if defined(MODE_NXDN)
+CNXDNRX nxdnRX;
+CNXDNTX nxdnTX;
+
+CCalNXDN calNXDN;
+#endif
+
+#if defined(MODE_M17)
+CM17RX m17RX;
+CM17TX m17TX;
+#endif
+
+#if defined(MODE_POCSAG)
+CPOCSAGTX  pocsagTX;
+CCalPOCSAG calPOCSAG;
+#endif
+
+#if defined(MODE_FM)
+CFM    fm;
+CCalFM calFM;
+#endif
+
+#if defined(MODE_AX25)
+CAX25RX ax25RX;
+CAX25TX ax25TX;
+#endif
+
+CCalRSSI calRSSI;
 
 CCWIdTX cwIdTX;
 
@@ -88,48 +118,84 @@ void loop()
   io.process();
 
   // The following is for transmitting
+#if defined(MODE_DSTAR)
   if (m_dstarEnable && m_modemState == STATE_DSTAR)
     dstarTX.process();
+#endif
 
+#if defined(MODE_DMR)
   if (m_dmrEnable && m_modemState == STATE_DMR) {
     if (m_duplex)
       dmrTX.process();
     else
       dmrDMOTX.process();
   }
+#endif
 
+#if defined(MODE_YSF)
   if (m_ysfEnable && m_modemState == STATE_YSF)
     ysfTX.process();
+#endif
 
+#if defined(MODE_P25)
   if (m_p25Enable && m_modemState == STATE_P25)
     p25TX.process();
+#endif
 
+#if defined(MODE_NXDN)
   if (m_nxdnEnable && m_modemState == STATE_NXDN)
     nxdnTX.process();
+#endif
 
+#if defined(MODE_M17)
+  if (m_m17Enable && m_modemState == STATE_M17)
+    m17TX.process();
+#endif
+
+#if defined(MODE_POCSAG)
   if (m_pocsagEnable && (m_modemState == STATE_POCSAG || pocsagTX.busy()))
     pocsagTX.process();
+#endif
 
+#if defined(MODE_AX25)
+  if (m_ax25Enable && (m_modemState == STATE_IDLE || m_modemState == STATE_FM))
+    ax25TX.process();
+#endif
+
+#if defined(MODE_FM)
   if (m_fmEnable && m_modemState == STATE_FM)
     fm.process();
+#endif
 
+#if defined(MODE_DSTAR)
   if (m_modemState == STATE_DSTARCAL)
     calDStarTX.process();
+#endif
 
+#if defined(MODE_DMR)
   if (m_modemState == STATE_DMRCAL || m_modemState == STATE_LFCAL || m_modemState == STATE_DMRCAL1K || m_modemState == STATE_DMRDMO1K)
     calDMR.process();
+#endif
 
+#if defined(MODE_FM)
+  if (m_modemState == STATE_FMCAL10K || m_modemState == STATE_FMCAL12K || m_modemState == STATE_FMCAL15K || m_modemState == STATE_FMCAL20K || m_modemState == STATE_FMCAL25K || m_modemState == STATE_FMCAL30K)
+    calFM.process();
+#endif
+
+#if defined(MODE_P25)
   if (m_modemState == STATE_P25CAL1K)
     calP25.process();
+#endif
 
+#if defined(MODE_NXDN)
   if (m_modemState == STATE_NXDNCAL1K)
     calNXDN.process();
+#endif
 
+#if defined(MODE_POCSAG)
   if (m_modemState == STATE_POCSAGCAL)
     calPOCSAG.process();
-
-  if (m_modemState == STATE_FMCAL10K || m_modemState == STATE_FMCAL12K || m_modemState == STATE_FMCAL15K || m_modemState == STATE_FMCAL20K || m_modemState == STATE_FMCAL25K ||m_modemState == STATE_FMCAL30K)
-    calFM.process();
+#endif
 
   if (m_modemState == STATE_IDLE)
     cwIdTX.process();

MMDVM.ino

@@ -28,45 +28,75 @@ bool m_dmrEnable    = true;
 bool m_ysfEnable    = true;
 bool m_p25Enable    = true;
 bool m_nxdnEnable   = true;
+bool m_m17Enable    = true;
 bool m_pocsagEnable = true;
 bool m_fmEnable     = true;
+bool m_ax25Enable   = true;
 
 bool m_duplex = true;
 
 bool m_tx  = false;
 bool m_dcd = false;
 
-CDStarRX   dstarRX;
-CDStarTX   dstarTX;
-
-CDMRIdleRX dmrIdleRX;
-CDMRRX     dmrRX;
-CDMRTX     dmrTX;
-
-CDMRDMORX  dmrDMORX;
-CDMRDMOTX  dmrDMOTX;
-
-CYSFRX     ysfRX;
-CYSFTX     ysfTX;
-
-CP25RX     p25RX;
-CP25TX     p25TX;
-
-CNXDNRX    nxdnRX;
-CNXDNTX    nxdnTX;
-
-CPOCSAGTX  pocsagTX;
-
-CFM        fm;
+#if defined(MODE_DSTAR)
+CDStarRX dstarRX;
+CDStarTX dstarTX;
 
 CCalDStarRX calDStarRX;
 CCalDStarTX calDStarTX;
-CCalDMR     calDMR;
-CCalFM      calFM;
-CCalP25     calP25;
-CCalNXDN    calNXDN;
-CCalPOCSAG  calPOCSAG;
-CCalRSSI    calRSSI;
+#endif
+
+#if defined(MODE_DMR)
+CDMRIdleRX dmrIdleRX;
+CDMRRX dmrRX;
+CDMRTX dmrTX;
+
+CDMRDMORX dmrDMORX;
+CDMRDMOTX dmrDMOTX;
+
+CCalDMR calDMR;
+#endif
+
+#if defined(MODE_YSF)
+CYSFRX ysfRX;
+CYSFTX ysfTX;
+#endif
+
+#if defined(MODE_P25)
+CP25RX p25RX;
+CP25TX p25TX;
+
+CCalP25 calP25;
+#endif
+
+#if defined(MODE_NXDN)
+CNXDNRX nxdnRX;
+CNXDNTX nxdnTX;
+
+CCalNXDN calNXDN;
+#endif
+
+#if defined(MODE_M17)
+CM17RX m17RX;
+CM17TX m17TX;
+#endif
+
+#if defined(MODE_POCSAG)
+CPOCSAGTX  pocsagTX;
+CCalPOCSAG calPOCSAG;
+#endif
+
+#if defined(MODE_FM)
+CFM    fm;
+CCalFM calFM;
+#endif
+
+#if defined(MODE_AX25)
+CAX25RX ax25RX;
+CAX25TX ax25TX;
+#endif
+
+CCalRSSI calRSSI;
 
 CCWIdTX cwIdTX;
 
@@ -85,49 +115,86 @@ void loop()
   io.process();
 
   // The following is for transmitting
+#if defined(MODE_DSTAR)
   if (m_dstarEnable && m_modemState == STATE_DSTAR)
     dstarTX.process();
+#endif
 
+#if defined(MODE_DMR)
   if (m_dmrEnable && m_modemState == STATE_DMR) {
     if (m_duplex)
       dmrTX.process();
     else
       dmrDMOTX.process();
   }
+#endif
 
+#if defined(MODE_YSF)
   if (m_ysfEnable && m_modemState == STATE_YSF)
     ysfTX.process();
+#endif
 
+#if defined(MODE_P25)
   if (m_p25Enable && m_modemState == STATE_P25)
     p25TX.process();
+#endif
 
+#if defined(MODE_NXDN)
   if (m_nxdnEnable && m_modemState == STATE_NXDN)
     nxdnTX.process();
+#endif
 
+#if defined(MODE_M17)
+  if (m_m17Enable && m_modemState == STATE_M17)
+    m17TX.process();
+#endif
+
+#if defined(MODE_POCSAG)
   if (m_pocsagEnable && (m_modemState == STATE_POCSAG || pocsagTX.busy()))
     pocsagTX.process();
+#endif
 
+#if defined(MODE_AX25)
+  if (m_ax25Enable && (m_modemState == STATE_IDLE || m_modemState == STATE_FM))
+    ax25TX.process();
+#endif
+
+#if defined(MODE_FM)
   if (m_fmEnable && m_modemState == STATE_FM)
     fm.process();
+#endif
 
+#if defined(MODE_DSTAR)
   if (m_modemState == STATE_DSTARCAL)
     calDStarTX.process();
+#endif
 
+#if defined(MODE_DMR)
   if (m_modemState == STATE_DMRCAL || m_modemState == STATE_LFCAL || m_modemState == STATE_DMRCAL1K || m_modemState == STATE_DMRDMO1K)
     calDMR.process();
+#endif
 
+#if defined(MODE_FM)
   if (m_modemState == STATE_FMCAL10K || m_modemState == STATE_FMCAL12K || m_modemState == STATE_FMCAL15K || m_modemState == STATE_FMCAL20K || m_modemState == STATE_FMCAL25K || m_modemState == STATE_FMCAL30K)
     calFM.process();
+#endif
 
+#if defined(MODE_P25)
   if (m_modemState == STATE_P25CAL1K)
     calP25.process();
+#endif
 
+#if defined(MODE_NXDN)
   if (m_modemState == STATE_NXDNCAL1K)
     calNXDN.process();
+#endif
 
+#if defined(MODE_POCSAG)
   if (m_modemState == STATE_POCSAGCAL)
     calPOCSAG.process();
+#endif
 
   if (m_modemState == STATE_IDLE)
     cwIdTX.process();
 }
+

Makefile

@@ -133,12 +133,18 @@ DEFS_PI_F722=-DUSE_HAL_DRIVER -DSTM32F722xx -DSTM32F7XX -DSTM32F722_PI -DHSE_VAL
 DEFS_F7M=-DUSE_HAL_DRIVER -DSTM32F722xx -DSTM32F7XX -DSTM32F722_F7M -DHSE_VALUE=$(OSC) -DMADEBYMAKEFILE
 # MMDVM_RPT_Hat F0DEI, DB9MAT, DF2ET board:
 DEFS_RPT_HAT=-DUSE_HAL_DRIVER -DSTM32F722xx -DSTM32F7XX -DSTM32F722_RPT_HAT -DHSE_VALUE=$(OSC) -DMADEBYMAKEFILE
-# STM32F4 DVM board:
+# RB STM32F4_DVM board:
 DEFS_DVM=-DUSE_STDPERIPH_DRIVER -DSTM32F4XX -DSTM32F446xx -DSTM32F4_DVM -DHSE_VALUE=$(OSC) -DMADEBYMAKEFILE
+# RB STM32F7 DVM board:
+DEFS_DVM722=-DUSE_HAL_DRIVER -DSTM32F722xx -DSTM32F7XX -DSTM32F7_DVM -DHSE_VALUE=$(OSC) -DMADEBYMAKEFILE
 # MMDVM_RPT_Hat BG4TGO, BG5HHP board:
 DEFS_RPT_HAT_TGO=-DUSE_STDPERIPH_DRIVER -DSTM32F4XX -DSTM32F40_41xxx -DSTM32F4_RPT_HAT_TGO -DHSE_VALUE=$(OSC) -DMADEBYMAKEFILE
 # DRCC_DVM BG7NQF board:
 DEFS_DRCC_DVM=-DUSE_STDPERIPH_DRIVER -DSTM32F4XX -DSTM32F446xx -DDRCC_DVM -DHSE_VALUE=$(OSC) -DMADEBYMAKEFILE
+# WA0EDA F405 MTR2K, MASTR3 board:
+DEFS_EDA_405=-DUSE_STDPERIPH_DRIVER -DSTM32F4XX -DSTM32F40_41xxx -DSTM32F4_EDA_405 -DHSE_VALUE=$(OSC) -DMADEBYMAKEFILE
+# WA0EDA F446 MTR2K, MASTR3 board:
+DEFS_EDA_446=-DUSE_STDPERIPH_DRIVER -DSTM32F4XX -DSTM32F446xx -DSTM32F4_EDA_446 -DHSE_VALUE=$(OSC) -DMADEBYMAKEFILE
 
 
 # Build compiler flags
@@ -155,7 +161,7 @@ LDFLAGS_F722 =-T stm32f722_link.ld $(MCFLAGS_F7) --specs=nosys.specs $(INCLUDES_
 # Common flags
 CFLAGS=-Os -ffunction-sections -fdata-sections -fno-builtin -Wno-implicit -DCUSTOM_NEW -DNO_EXCEPTIONS
 CXXFLAGS=-Os -fno-exceptions -ffunction-sections -fdata-sections -fno-builtin -fno-rtti -DCUSTOM_NEW -DNO_EXCEPTIONS
-LDFLAGS=-Os --specs=nano.specs
+LDFLAGS=-Os --specs=nano.specs -Wl,-Map=bin/mmdvm.map
 
 # Build Rules
 .PHONY: all release dis pi pi-f722 f4m nucleo f767 dvm drcc_nqf clean
@@ -218,17 +224,41 @@ f767: LDFLAGS+=$(LDFLAGS_F767)
 f767: release_f7
 
 dvm: GitVersion.h
-dvm: CFLAGS+=$(CFLAGS_F4) $(DEFS_DVM)
-dvm: CXXFLAGS+=$(CXXFLAGS_F4) $(DEFS_DVM)
+dvm: CFLAGS+=$(CFLAGS_F4) $(DEFS_DVM) -DDRCC_DVM_446
+dvm: CXXFLAGS+=$(CXXFLAGS_F4) $(DEFS_DVM) -DDRCC_DVM_446
 dvm: LDFLAGS+=$(LDFLAGS_F4)
 dvm: release_f4
 
+dvm722: GitVersion.h
+dvm722: CFLAGS+=$(CFLAGS_F7) $(DEFS_DVM722) -DDRCC_DVM_722
+dvm722: CXXFLAGS+=$(CXXFLAGS_F7) $(DEFS_DVM722) -DDRCC_DVM_722
+dvm722: LDFLAGS+=$(LDFLAGS_F722)
+dvm722: release_f7
+
 drcc_nqf: GitVersion.h
 drcc_nqf: CFLAGS+=$(CFLAGS_F4) $(DEFS_DRCC_DVM) -DDRCC_DVM_NQF
 drcc_nqf: CXXFLAGS+=$(CXXFLAGS_F4) $(DEFS_DRCC_DVM) -DDRCC_DVM_NQF
 drcc_nqf: LDFLAGS+=$(LDFLAGS_F4)
 drcc_nqf: release_f4
 
+hhp446: GitVersion.h
+hhp446: CFLAGS+=$(CFLAGS_F4) $(DEFS_DRCC_DVM) -DDRCC_DVM_HHP446
+hhp446: CXXFLAGS+=$(CXXFLAGS_F4) $(DEFS_DRCC_DVM) -DDRCC_DVM_HHP446
+hhp446: LDFLAGS+=$(LDFLAGS_F4)
+hhp446: release_f4
+
+eda405: GitVersion.h
+eda405: CFLAGS+=$(CFLAGS_F4) $(DEFS_EDA_405)
+eda405: CXXFLAGS+=$(CXXFLAGS_F4) $(DEFS_EDA_405)
+eda405: LDFLAGS+=$(LDFLAGS_F4)
+eda405: release_f4
+
+eda446: GitVersion.h
+eda446: CFLAGS+=$(CFLAGS_F4) $(DEFS_EDA_446)
+eda446: CXXFLAGS+=$(CXXFLAGS_F4) $(DEFS_EDA_446)
+eda446: LDFLAGS+=$(LDFLAGS_F4)
+eda446: release_f4
+
 release_f4: $(BINDIR)
 release_f4: $(OBJDIR_F4)
 release_f4: $(BINDIR)/$(BINHEX_F4)
@@ -338,27 +368,27 @@ endif
 deploy-pi:
 ifneq ($(wildcard /usr/local/bin/stm32flash),)
 	-/usr/local/bin/stm32flash -i 20,-21,21:-20,21 /dev/ttyAMA0
-	-/usr/local/bin/stm32ld /dev/ttyAMA0 57600 bin/$(BINBIN_F4)
-	/usr/local/bin/stm32flash -v -w bin/$(BINBIN_F4) -g 0x0 -R -c /dev/ttyAMA0
+	/usr/local/bin/stm32flash -v -w bin/$(BINBIN_F4) -g 0x0 -R /dev/ttyAMA0
 endif
 
 ifneq ($(wildcard /usr/bin/stm32flash),)
 	-/usr/bin/stm32flash -i 20,-21,21:-20,21 /dev/ttyAMA0
-	-/usr/bin/stm32ld /dev/ttyAMA0 57600 bin/$(BINBIN_F4)
-	/usr/bin/stm32flash -v -w bin/$(BINBIN_F4) -g 0x0 -R -c /dev/ttyAMA0
+	/usr/bin/stm32flash -v -w bin/$(BINBIN_F4) -g 0x0 -R /dev/ttyAMA0
 endif
 
 deploy-f4m: deploy-pi
 deploy-dvm: deploy-pi
+deploy-eda405: deploy-pi
+deploy-eda446: deploy-pi
 
 deploy-pi-f7:
 ifneq ($(wildcard /usr/local/bin/stm32flash),)
 	-/usr/local/bin/stm32flash -i 20,-21,21:-20,21 /dev/ttyAMA0
-	/usr/local/bin/stm32flash -v -w bin/$(BINBIN_F7) -g 0x0 -R -c /dev/ttyAMA0
+	/usr/local/bin/stm32flash -v -w bin/$(BINBIN_F7) -g 0x0 -R /dev/ttyAMA0
 
 else ifneq ($(wildcard /usr/bin/stm32flash),)
 	-/usr/bin/stm32flash -i 20,-21,21:-20,21 /dev/ttyAMA0
-	/usr/bin/stm32flash -v -w bin/$(BINBIN_F7) -g 0x0 -R -c /dev/ttyAMA0
+	/usr/bin/stm32flash -v -w bin/$(BINBIN_F7) -g 0x0 -R /dev/ttyAMA0
 endif
 
 deploy-f7m:   deploy-pi-f7

Makefile.Arduino

@@ -1,5 +1,5 @@
 #!/usr/bin/make
-# makefile for the arduino due (works with arduino IDE 1.6.11)
+# makefile for the arduino due (works with arduino IDE 1.6.12)
 #
 # The original file can be found at https://github.com/pauldreik/arduino-due-makefile
 #
@@ -34,7 +34,7 @@ OBJCOPY:=$(ADIR)/packages/arduino/tools/arm-none-eabi-gcc/4.8.3-2014q1/bin/arm-n
 
 C:=$(CC)
 #SAM:=arduino/sam/
-SAM:=$(ADIR)/packages/arduino/hardware/sam/1.6.11
+SAM:=$(ADIR)/packages/arduino/hardware/sam/1.6.12
 #CMSIS:=arduino/sam/system/CMSIS/
 #LIBSAM:=arduino/sam/system/libsam
 TMPDIR:=$(PWD)/build

NXDNRX.cpp

@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2009-2018 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2009-2018,2020 by Jonathan Naylor G4KLX
  *
  *   This program is free software; you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
@@ -17,6 +17,9 @@
  */
 
 #include "Config.h"
+
+#if defined(MODE_NXDN)
+
 #include "Globals.h"
 #include "NXDNRX.h"
 #include "Utils.h"
@@ -403,3 +406,5 @@ void CNXDNRX::writeRSSIData(uint8_t* data)
   m_rssiCount = 0U;
 }
 
+#endif
+

NXDNRX.h

@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2015,2016,2017,2018 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2015,2016,2017,2018,2020 by Jonathan Naylor G4KLX
  *
  *   This program is free software; you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
@@ -16,10 +16,13 @@
  *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  */
 
+#include "Config.h"
+
+#if defined(MODE_NXDN)
+
 #if !defined(NXDNRX_H)
 #define  NXDNRX_H
 
-#include "Config.h"
 #include "NXDNDefines.h"
 
 enum NXDNRX_STATE {
@@ -67,3 +70,5 @@ private:
 
 #endif
 
+#endif
+

NXDNTX.cpp

@@ -18,6 +18,9 @@
  */
 
 #include "Config.h"
+
+#if defined(MODE_NXDN)
+
 #include "Globals.h"
 #include "NXDNTX.h"
 
@@ -54,7 +57,7 @@ m_poBuffer(),
 m_poLen(0U),
 m_poPtr(0U),
 m_txDelay(240U),     // 200ms
-m_txHang(6000U),     // 5s
+m_txHang(3000U),     // 5s
 m_txCount(0U)
 {
   ::memset(m_modState, 0x00U, 16U * sizeof(q15_t));
@@ -72,10 +75,7 @@ m_txCount(0U)
 
 void CNXDNTX::process()
 {
-  if (m_buffer.getData() == 0U && m_poLen == 0U && m_txCount == 0U)
-    return;
-
-  if (m_poLen == 0U) {
+  if (m_poLen == 0U && m_buffer.getData() > 0U) {
     if (!m_tx) {
       for (uint16_t i = 0U; i < m_txDelay; i++)
         m_poBuffer[m_poLen++] = NXDN_SYNC;
@@ -84,7 +84,8 @@ void CNXDNTX::process()
       m_poBuffer[m_poLen++] = NXDN_PREAMBLE[2U];
     } else {
       for (uint8_t i = 0U; i < NXDN_FRAME_LENGTH_BYTES; i++) {
-        uint8_t c = m_buffer.get();
+        uint8_t c = 0U;
+        m_buffer.get(c);
         m_poBuffer[m_poLen++] = c;
       }
     }
@@ -125,7 +126,7 @@ void CNXDNTX::process()
   }
 }
 
-uint8_t CNXDNTX::writeData(const uint8_t* data, uint8_t length)
+uint8_t CNXDNTX::writeData(const uint8_t* data, uint16_t length)
 {
   if (length != (NXDN_FRAME_LENGTH_BYTES + 1U))
     return 4U;
@@ -200,5 +201,8 @@ uint8_t CNXDNTX::getSpace() const
 
 void CNXDNTX::setParams(uint8_t txHang)
 {
-  m_txHang = txHang * 1200U;
+  m_txHang = txHang * 600U;
 }
+
+#endif
+

NXDNTX.h

@@ -16,18 +16,20 @@
  *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  */
 
+#include "Config.h"
+
+#if defined(MODE_NXDN)
+
 #if !defined(NXDNTX_H)
 #define  NXDNTX_H
 
-#include "Config.h"
-
-#include "SerialRB.h"
+#include "RingBuffer.h"
 
 class CNXDNTX {
 public:
   CNXDNTX();
 
-  uint8_t writeData(const uint8_t* data, uint8_t length);
+  uint8_t writeData(const uint8_t* data, uint16_t length);
 
   void process();
 
@@ -38,7 +40,7 @@ public:
   void setParams(uint8_t txHang);
 
 private:
-  CSerialRB                        m_buffer;
+  CRingBuffer<uint8_t>                        m_buffer;
   arm_fir_interpolate_instance_q15 m_modFilter;
   arm_fir_instance_q15             m_sincFilter;
   q15_t                            m_modState[16U];    // blockSize + phaseLength - 1, 4 + 9 - 1 plus some spare
@@ -55,3 +57,6 @@ private:
 };
 
 #endif
+
+#endif
+

P25RX.cpp

@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2009-2017 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2009-2017,2020 by Jonathan Naylor G4KLX
  *   Copyright (C) 2018 by Bryan Biedenkapp <gatekeep@gmail.com>
  *
  *   This program is free software; you can redistribute it and/or modify
@@ -18,6 +18,9 @@
  */
 
 #include "Config.h"
+
+#if defined(MODE_P25)
+
 #include "Globals.h"
 #include "P25RX.h"
 #include "Utils.h"
@@ -535,3 +538,6 @@ void CP25RX::writeRSSILdu(uint8_t* ldu)
   m_rssiAccum = 0U;
   m_rssiCount = 0U;
 }
+
+#endif
+

P25RX.h

@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2015,2016,2017 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2015,2016,2017,2020 by Jonathan Naylor G4KLX
  *   Copyright (C) 2018 by Bryan Biedenkapp <gatekeep@gmail.com>
  *
  *   This program is free software; you can redistribute it and/or modify
@@ -17,10 +17,13 @@
  *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  */
 
+#include "Config.h"
+
+#if defined(MODE_P25)
+
 #if !defined(P25RX_H)
 #define  P25RX_H
 
-#include "Config.h"
 #include "P25Defines.h"
 
 enum P25RX_STATE {
@@ -72,3 +75,6 @@ private:
 };
 
 #endif
+
+#endif
+

P25TX.cpp

@@ -18,6 +18,9 @@
  */
 
 #include "Config.h"
+
+#if defined(MODE_P25)
+
 #include "Globals.h"
 #include "P25TX.h"
 
@@ -70,17 +73,16 @@ m_txCount(0U)
 
 void CP25TX::process()
 {
-  if (m_buffer.getData() == 0U && m_poLen == 0U && m_txCount == 0U)
-    return;
-
-  if (m_poLen == 0U) {
+  if (m_poLen == 0U && m_buffer.getData() > 0U) {
     if (!m_tx) {
       for (uint16_t i = 0U; i < m_txDelay; i++)
         m_poBuffer[m_poLen++] = P25_START_SYNC;
     } else {
-      uint8_t length = m_buffer.get();
+      uint8_t length;
+      m_buffer.get(length);
       for (uint8_t i = 0U; i < length; i++) {
-        uint8_t c = m_buffer.get();
+        uint8_t c = 0U;
+        m_buffer.get(c);
         m_poBuffer[m_poLen++] = c;
       }
     }
@@ -121,7 +123,7 @@ void CP25TX::process()
   }
 }
 
-uint8_t CP25TX::writeData(const uint8_t* data, uint8_t length)
+uint8_t CP25TX::writeData(const uint8_t* data, uint16_t length)
 {
   if (length < (P25_TERM_FRAME_LENGTH_BYTES + 1U))
     return 4U;
@@ -199,3 +201,6 @@ void CP25TX::setParams(uint8_t txHang)
 {
   m_txHang = txHang * 1200U;
 }
+
+#endif
+

P25TX.h

@@ -16,18 +16,20 @@
  *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  */
 
+#include "Config.h"
+
+#if defined(MODE_P25)
+
 #if !defined(P25TX_H)
 #define  P25TX_H
 
-#include "Config.h"
-
-#include "SerialRB.h"
+#include "RingBuffer.h"
 
 class CP25TX {
 public:
   CP25TX();
 
-  uint8_t writeData(const uint8_t* data, uint8_t length);
+  uint8_t writeData(const uint8_t* data, uint16_t length);
 
   void process();
 
@@ -38,7 +40,7 @@ public:
   void setParams(uint8_t txHang);
 
 private:
-  CSerialRB                        m_buffer;
+  CRingBuffer<uint8_t>                        m_buffer;
   arm_fir_interpolate_instance_q15 m_modFilter;
   arm_fir_instance_q15             m_lpFilter;
   q15_t                            m_modState[16U];    // blockSize + phaseLength - 1, 4 + 9 - 1 plus some spare
@@ -55,3 +57,6 @@ private:
 };
 
 #endif
+
+#endif
+

POCSAGTX.cpp

@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2009-2018 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2009-2018,2020 by Jonathan Naylor G4KLX
  *
  *   This program is free software; you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
@@ -17,6 +17,9 @@
  */
 
 #include "Config.h"
+
+#if defined(MODE_POCSAG)
+
 #include "Globals.h"
 #include "POCSAGTX.h"
 
@@ -61,7 +64,8 @@ void CPOCSAGTX::process()
         m_poBuffer[m_poLen++] = POCSAG_SYNC;
     } else {
       for (uint8_t i = 0U; i < POCSAG_FRAME_LENGTH_BYTES; i++) {
-        uint8_t c = m_buffer.get();
+        uint8_t c = 0U;
+        m_buffer.get(c);
         m_poBuffer[m_poLen++] = c;
       }
     }
@@ -95,7 +99,7 @@ bool CPOCSAGTX::busy()
     return false;
 }
 
-uint8_t CPOCSAGTX::writeData(const uint8_t* data, uint8_t length)
+uint8_t CPOCSAGTX::writeData(const uint8_t* data, uint16_t length)
 {
   if (length != POCSAG_FRAME_LENGTH_BYTES)
     return 4U;
@@ -147,3 +151,5 @@ uint8_t CPOCSAGTX::getSpace() const
   return m_buffer.getSpace() / POCSAG_FRAME_LENGTH_BYTES;
 }
 
+#endif
+

POCSAGTX.h

@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2015-2019 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2015-2020 by Jonathan Naylor G4KLX
  *
  *   This program is free software; you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
@@ -16,18 +16,20 @@
  *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  */
 
+#include "Config.h"
+
+#if defined(MODE_POCSAG)
+
 #if !defined(POCSAGTX_H)
 #define  POCSAGTX_H
 
-#include "Config.h"
-
-#include "SerialRB.h"
+#include "RingBuffer.h"
 
 class CPOCSAGTX {
 public:
   CPOCSAGTX();
 
-  uint8_t writeData(const uint8_t* data, uint8_t length);
+  uint8_t writeData(const uint8_t* data, uint16_t length);
 
   void writeByte(uint8_t c);
 
@@ -40,7 +42,7 @@ public:
   bool busy();
 
 private:
-  CSerialRB            m_buffer;
+  CRingBuffer<uint8_t>            m_buffer;
   arm_fir_instance_q15 m_modFilter;
   q15_t                m_modState[170U];     // NoTaps + BlockSize - 1, 6 + 160 - 1 plus some spare
   uint8_t              m_poBuffer[200U];
@@ -51,3 +53,5 @@ private:
 
 #endif
 
+#endif
+

README.md

@@ -1,7 +1,17 @@
-This is the source code of the MMDVM firmware that supports D-Star, DMR, System Fusion, P25, NXDN, and POCSAG modes.
+This is the source code of the MMDVM firmware that supports D-Star, DMR,
+System Fusion, P25, NXDN, POCSAG, and FM modes.
 
-It runs on the Arduino Due, the ST-Micro STM32F1xxx, STM32F4xxx and STM32F7xxx processors, as well as the Teensy 3.1/3.2/3.5/3.6. What these platforms have in common is the use of an ARM Cortex-M3 or M4 processor with a clock speed greater than 70 MHz, and access to at least one analogue to digital converter and one digital to analogue converter.
+It runs on the Arduino Due, the ST-Micro STM32F1xxx, STM32F4xxx and STM32F7xxx
+processors, as well as the Teensy 3.1/3.2/3.5/3.6. What these platforms have in
+common is the use of an ARM Cortex-M3, M4, or M7 processors with a clock speed
+greater than 70 MHz, and access to at least one analogue to digital converter
+and one digital to analogue converter.
 
-In order to build this software for the Arduino Due, you will need to edit a file within the Arduino GUI and that is detailed in the BUILD.txt file. The STM32 support is being supplied via the Coocox IDE with ARM GCC. The Teensy support uses Teensyduino.
+In order to build this software for the Arduino Due, you will need to edit a
+file within the Arduino GUI and that is detailed in the BUILD.txt file. The
+STM32 support is being supplied via the ARM GCC compiler. The Teensy support
+uses Teensyduino.
 
-This software is licenced under the GPL v2 and is intended for amateur and educational use only. Use of this software for commercial purposes is strictly forbidden.
+This software is licenced under the GPL v2 and is intended for amateur and
+educational use only. Use of this software for commercial purposes is strictly
+forbidden.

RSSIRB.cpp

@@ -1,102 +0,0 @@
-/*
-TX fifo control - Copyright (C) KI6ZUM 2015
-Copyright (C) 2015,2016 by Jonathan Naylor G4KLX
-
-This library is free software; you can redistribute it and/or
-modify it under the terms of the GNU Library General Public
-License as published by the Free Software Foundation; either
-version 2 of the License, or (at your option) any later version.
-
-This library is distributed in the hope that it will be useful,
-but WITHOUT ANY WARRANTY; without even the implied warranty of
-MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-Library General Public License for more details.
-
-You should have received a copy of the GNU Library General Public
-License along with this library; if not, write to the
-Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
-Boston, MA  02110-1301, USA.
-*/
-
-#include "RSSIRB.h"
-
-CRSSIRB::CRSSIRB(uint16_t length) :
-m_length(length),
-m_head(0U),
-m_tail(0U),
-m_full(false),
-m_overflow(false)
-{
-  m_rssi = new uint16_t[length];
-}
-
-uint16_t CRSSIRB::getSpace() const
-{
-  uint16_t n = 0U;
-
-  if (m_tail == m_head)
-    n = m_full ? 0U : m_length;
-  else if (m_tail < m_head)
-    n = m_length - m_head + m_tail;
-  else
-    n = m_tail - m_head;
-
-  if (n > m_length)
-    n = 0U;
-
-  return n;
-}
-
-uint16_t CRSSIRB::getData() const
-{
-  if (m_tail == m_head)
-    return m_full ? m_length : 0U;
-  else if (m_tail < m_head)
-    return m_head - m_tail;
-  else
-    return m_length - m_tail + m_head;
-}
-
-bool CRSSIRB::put(uint16_t rssi)
-{
-  if (m_full) {
-    m_overflow = true;
-    return false;
-  }
-
-  m_rssi[m_head] = rssi;
-
-  m_head++;
-  if (m_head >= m_length)
-    m_head = 0U;
-
-  if (m_head == m_tail)
-    m_full = true;
-
-  return true;
-}
-
-bool CRSSIRB::get(uint16_t& rssi)
-{
-  if (m_head == m_tail && !m_full)
-    return false;
-
-  rssi  = m_rssi[m_tail];
-
-  m_full = false;
-
-  m_tail++;
-  if (m_tail >= m_length)
-    m_tail = 0U;
-
-  return true;
-}
-
-bool CRSSIRB::hasOverflowed()
-{
-  bool overflow = m_overflow;
-
-  m_overflow = false;
-
-  return overflow;
-}