Add the timeout tones.

FM.cpp

@@ -56,10 +56,13 @@ void CFM::samples(q15_t* samples, uint8_t length)
       samples[i] = 0;
   }
 
+  if (!m_callsign.isRunning())
     m_rfAck.getAudio(samples, length);
 
+  if (!m_rfAck.isRunning())
     m_callsign.getAudio(samples, length);
 
+  if (!m_callsign.isRunning() && !m_rfAck.isRunning())
     m_timeoutTone.getAudio(samples, length);
 
   // Band-pass filter

FMKeyer.cpp

@@ -20,6 +20,61 @@
 #include "Globals.h"
 #include "FMKeyer.h"
 
+const struct {
+  uint8_t  c;
+  uint32_t pattern;
+  uint8_t  length;
+} SYMBOL_LIST[] = {
+  {'A', 0xB8000000U, 8U},
+  {'B', 0xEA800000U, 12U},
+  {'C', 0xEBA00000U, 14U},
+  {'D', 0xEA000000U, 10U},
+  {'E', 0x80000000U, 4U},
+  {'F', 0xAE800000U, 12U},
+  {'G', 0xEE800000U, 12U},
+  {'H', 0xAA000000U, 10U},
+  {'I', 0xA0000000U, 6U},
+  {'J', 0xBBB80000U, 16U},
+  {'K', 0xEB800000U, 12U},
+  {'L', 0xBA800000U, 12U},
+  {'M', 0xEE000000U, 10U},
+  {'N', 0xE8000000U, 8U},
+  {'O', 0xEEE00000U, 14U},
+  {'P', 0xBBA00000U, 14U},
+  {'Q', 0xEEB80000U, 16U},
+  {'R', 0xBA000000U, 10U},
+  {'S', 0xA8000000U, 8U},
+  {'T', 0xE0000000U, 6U},
+  {'U', 0xAE000000U, 10U},
+  {'V', 0xAB800000U, 12U},
+  {'W', 0xBB800000U, 12U},
+  {'X', 0xEAE00000U, 14U},
+  {'Y', 0xEBB80000U, 16U},
+  {'Z', 0xEEA00000U, 14U},
+  {'1', 0xBBBB8000U, 20U},
+  {'2', 0xAEEE0000U, 18U},
+  {'3', 0xABB80000U, 16U},
+  {'4', 0xAAE00000U, 14U},
+  {'5', 0xAA800000U, 12U},
+  {'6', 0xEAA00000U, 14U},
+  {'7', 0xEEA80000U, 16U},
+  {'8', 0xEEEA0000U, 18U},
+  {'9', 0xEEEE8000U, 20U},
+  {'0', 0xEEEEE000U, 22U},
+  {'/', 0xEAE80000U, 16U},
+  {'?', 0xAEEA0000U, 18U},
+  {',', 0xEEAEE000U, 22U},
+  {'-', 0xEAAE0000U, 18U},
+  {'=', 0xEAB80000U, 16U},
+  {' ', 0x00000000U, 4U},
+  {0U,  0x00000000U, 0U}
+};
+
+const uint8_t BIT_MASK_TABLE[] = {0x80U, 0x40U, 0x20U, 0x10U, 0x08U, 0x04U, 0x02U, 0x01U};
+
+#define WRITE_BIT(p,i,b) p[(i)>>3] = (b) ? (p[(i)>>3] | BIT_MASK_TABLE[(i)&7]) : (p[(i)>>3] & ~BIT_MASK_TABLE[(i)&7])
+#define READ_BIT(p,i)    (p[(i)>>3] & BIT_MASK_TABLE[(i)&7])
+
 CFMKeyer::CFMKeyer() :
 m_level(128 * 128),
 m_wanted(false),

FMTimeout.cpp

@@ -20,9 +20,17 @@
 #include "Globals.h"
 #include "FMTimeout.h"
 
+// 400 Hz sine wave at 24000 Hz sample rate
+const q15_t BUSY_AUDIO[] = {0, 3426, 6813, 10126, 13328, 16384, 19261, 21926, 24351, 26510, 28378, 29935, 31164, 32052, 32588, 32768, 32588, 32052, 31164, 29935, 28378, 26510, 24351,
+                            21926, 19261, 16384, 13328, 10126, 6813, 3425, 0, -3425, -6813, -10126, -13328, -16384, -19261, -21926, -24351, -26510, -28378, -29935, -31164, -32052,
+                            -32588, -32768, -32588, -32052, -31164, -29935, -28378, -26510, -24351, -21926, -19261, -16384, -13328, -10126, -6813, -3425};
+const uint8_t BUSY_AUDIO_LEN = 60U;
+
 CFMTimeout::CFMTimeout() :
 m_level(128 * 128),
-m_running(false)
+m_running(false),
+m_pos(0U),
+m_n(0U)
 {
 }
 
@@ -33,11 +41,32 @@ void CFMTimeout::setParams(uint8_t level)
 
 void CFMTimeout::getAudio(q15_t* samples, uint8_t length)
 {
+  if (!m_running)
+    return;
+
+  for (uint8_t i = 0U; i < length; i++) {
+    if (m_pos > 12000U) {
+      q31_t sample = BUSY_AUDIO[m_n] * m_level;
+      samples[i] = q15_t(__SSAT((sample >> 15), 16));
+
+      m_n++;
+      if (m_n >= BUSY_AUDIO_LEN)
+        m_n = 0U;
+    } else {
+      samples[i] = 0;
+    }
+
+    m_pos++;
+    if (m_pos >= 24000U)
+      m_pos = 0U;
+  }
 }
 
 void CFMTimeout::start()
 {
   m_running = true;
+  m_pos = 0U;
+  m_n   = 0U;
 }
 
 void CFMTimeout::stop()

FMTimeout.h

@@ -35,6 +35,8 @@ public:
 private:
   q15_t    m_level;
   bool     m_running;
+  uint32_t m_pos;
+  uint8_t  m_n;
 };
 
 #endif