CommandStation-EX/DCCWaveform.h

110 lines
3.9 KiB
C++

/*
* © 2021 M Steve Todd
* © 2021 Mike S
* © 2021 Fred Decker
* © 2020-2021 Harald Barth
* © 2020-2021 Chris Harlow
* All rights reserved.
*
* This file is part of CommandStation-EX
*
* This 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 3 of the License, or
* (at your option) any later version.
*
* It 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 CommandStation. If not, see <https://www.gnu.org/licenses/>.
*/
#ifndef DCCWaveform_h
#define DCCWaveform_h
#include "MotorDriver.h"
#ifdef ARDUINO_ARCH_ESP32
#include "DCCRMT.h"
#include "TrackManager.h"
#endif
// Number of preamble bits.
const int PREAMBLE_BITS_MAIN = 16;
const int PREAMBLE_BITS_PROG = 22;
const byte MAX_PACKET_SIZE = 5; // NMRA standard extended packets, payload size WITHOUT checksum.
// The WAVE_STATE enum is deliberately numbered because a change of order would be catastrophic
// to the transform array.
enum WAVE_STATE : byte {WAVE_START=0,WAVE_MID_1=1,WAVE_HIGH_0=2,WAVE_MID_0=3,WAVE_LOW_0=4,WAVE_PENDING=5};
// NOTE: static functions are used for the overall controller, then
// one instance is created for each track.
class DCCWaveform {
public:
DCCWaveform( byte preambleBits, bool isMain);
static void begin();
static void loop();
static DCCWaveform mainTrack;
static DCCWaveform progTrack;
inline void clearRepeats() { transmitRepeats=0; }
#ifndef ARDUINO_ARCH_ESP32
inline void clearResets() { sentResetsSincePacket=0; }
inline byte getResets() { return sentResetsSincePacket; }
#else
// extrafudge is added when we know that the resets will first come extrafudge packets in the future
inline void clearResets(byte extrafudge=0) {
if ((isMainTrack ? rmtMainChannel : rmtProgChannel) == NULL) return;
resetPacketBase = isMainTrack ? rmtMainChannel->packetCount() : rmtProgChannel->packetCount();
resetPacketBase += extrafudge;
};
inline byte getResets() {
if ((isMainTrack ? rmtMainChannel : rmtProgChannel) == NULL) return 0;
uint32_t packetcount = isMainTrack ?
rmtMainChannel->packetCount() : rmtProgChannel->packetCount();
uint32_t count = packetcount - resetPacketBase; // Beware of unsigned interger arithmetic.
if (count > UINT32_MAX/2) // we are in the extrafudge area
return 0;
if (count > 255) // cap to 255
return 255;
return count; // all special cases handled above
};
#endif
void schedulePacket(const byte buffer[], byte byteCount, byte repeats);
bool getPacketPending();
private:
#ifndef ARDUINO_ARCH_ESP32
volatile bool packetPending;
volatile byte sentResetsSincePacket;
#else
volatile uint32_t resetPacketBase;
#endif
static void interruptHandler();
void interrupt2();
bool isMainTrack;
// Transmission controller
byte transmitPacket[MAX_PACKET_SIZE+1]; // +1 for checksum
byte transmitLength;
byte transmitRepeats; // remaining repeats of transmission
byte remainingPreambles;
byte requiredPreambles;
byte bits_sent; // 0-8 (yes 9 bits) sent for current byte
byte bytes_sent; // number of bytes sent from transmitPacket
WAVE_STATE state; // wave generator state machine
byte pendingPacket[MAX_PACKET_SIZE+1]; // +1 for checksum
byte pendingLength;
byte pendingRepeats;
#ifdef ARDUINO_ARCH_ESP32
static RMTChannel *rmtMainChannel;
static RMTChannel *rmtProgChannel;
#endif
};
#endif