MMDVM/AX25Demodulator.cpp

62 lines
1.5 KiB
C++

/*
* 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"
#include "Globals.h"
#include "AX25Demodulator.h"
const float DELAY = 0.000448F;
const float SAMPLE_RATE = 24000.0F;
const uint16_t DELAY_LEN = uint16_t((DELAY / (1.0F / SAMPLE_RATE)) + 0.5F);
CAX25Demodulator::CAX25Demodulator() :
m_delayLine(NULL),
m_delayPos(0U),
m_nrziState(false)
{
m_delayLine = new bool[2U * DELAY_LEN];
}
bool CAX25Demodulator::process(const q15_t* samples, uint8_t length, CAX25Frame& frame)
{
return false;
}
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;
}