remove packetPendingRMT from wrong if

CommandStation-EX.ino

@@ -58,6 +58,9 @@ void setup()
   // Responsibility 1: Start the usb connection for diagnostics
   // This is normally Serial but uses SerialUSB on a SAMD processor
   Serial.begin(115200);
+#ifdef ESP_DEBUG
+  Serial.setDebugOutput(true);
+#endif
 
   DIAG(F("License GPLv3 fsf.org (c) dcc-ex.com"));
 
@@ -71,9 +74,12 @@ void setup()
   // Start the WiFi interface on a MEGA, Uno cannot currently handle WiFi
   // Start Ethernet if it exists
 #if WIFI_ON
+#ifndef ESP_FAMILY
   WifiInterface::setup(WIFI_SERIAL_LINK_SPEED, F(WIFI_SSID), F(WIFI_PASSWORD), F(WIFI_HOSTNAME), IP_PORT, WIFI_CHANNEL);
+#else
+  WifiESP::setup(WIFI_SSID, WIFI_PASSWORD, WIFI_HOSTNAME, IP_PORT, WIFI_CHANNEL);
+#endif
 #endif // WIFI_ON
-
 #if ETHERNET_ON
   EthernetInterface::setup();
 #endif // ETHERNET_ON
@@ -112,14 +118,18 @@ void loop()
   // Responsibility 1: Handle DCC background processes
   //                   (loco reminders and power checks)
   DCC::loop();
-
   // Responsibility 2: handle any incoming commands on USB connection
   serialParser.loop(Serial);
 
 // Responsibility 3: Optionally handle any incoming WiFi traffic
 #if WIFI_ON
+#ifndef ESP_FAMILY
   WifiInterface::loop();
 #endif
+#if defined(ARDUINO_ARCH_ESP8266) // on ESP32 own task
+  WifiESP::loop();
+#endif
+#endif //WIFI_ON
 #if ETHERNET_ON
   EthernetInterface::loop();
 #endif
@@ -137,7 +147,9 @@ void loop()
   
   // Report any decrease in memory (will automatically trigger on first call)
   static int ramLowWatermark = __INT_MAX__; // replaced on first loop 
-
+#ifdef ESP_FAMILY
+  updateMinimumFreeMemory(128);
+#endif
   int freeNow = minimumFreeMemory();
   if (freeNow < ramLowWatermark)
   {

DCC.cpp

@@ -311,14 +311,14 @@ const ackOp FLASH WRITE_BIT0_PROG[] = {
      W0,WACK,
      V0, WACK,  // validate bit is 0 
      ITC1,      // if acked, callback(1)
-     FAIL  // callback (-1)
+     CALLFAIL  // callback (-1)
 };
 const ackOp FLASH WRITE_BIT1_PROG[] = {
      BASELINE,
      W1,WACK,
      V1, WACK,  // validate bit is 1 
      ITC1,      // if acked, callback(1)
-     FAIL  // callback (-1)
+     CALLFAIL  // callback (-1)
 };
 
 const ackOp FLASH VERIFY_BIT0_PROG[] = {
@@ -327,7 +327,7 @@ const ackOp FLASH VERIFY_BIT0_PROG[] = {
      ITC0,      // if acked, callback(0)
      V1, WACK,  // validate bit is 1
      ITC1,       
-     FAIL  // callback (-1)
+     CALLFAIL  // callback (-1)
 };
 const ackOp FLASH VERIFY_BIT1_PROG[] = {
      BASELINE,
@@ -335,7 +335,7 @@ const ackOp FLASH VERIFY_BIT1_PROG[] = {
      ITC1,      // if acked, callback(1)
      V0, WACK, 
      ITC0,
-     FAIL  // callback (-1)
+     CALLFAIL  // callback (-1)
 };
 
 const ackOp FLASH READ_BIT_PROG[] = {
@@ -344,7 +344,7 @@ const ackOp FLASH READ_BIT_PROG[] = {
      ITC1,      // if acked, callback(1)
      V0, WACK,  // validate bit is zero
      ITC0,      // if acked callback 0
-     FAIL       // bit not readable 
+     CALLFAIL       // bit not readable 
      };
      
 const ackOp FLASH WRITE_BYTE_PROG[] = {
@@ -352,7 +352,7 @@ const ackOp FLASH WRITE_BYTE_PROG[] = {
       WB,WACK,ITC1,    // Write and callback(1) if ACK 
       // handle decoders that dont ack a write 
       VB,WACK,ITC1,    // validate byte and callback(1) if correct 
-      FAIL        // callback (-1)
+      CALLFAIL        // callback (-1)
       };
       
 const ackOp FLASH VERIFY_BYTE_PROG[] = {
@@ -378,7 +378,7 @@ const ackOp FLASH VERIFY_BYTE_PROG[] = {
       V0, WACK, MERGE,
       V0, WACK, MERGE,
       VB, WACK, ITCBV,  // verify merged byte and return it if acked ok - with retry report
-      FAIL };
+      CALLFAIL };
       
       
 const ackOp FLASH READ_CV_PROG[] = {
@@ -401,7 +401,7 @@ const ackOp FLASH READ_CV_PROG[] = {
       V0, WACK, MERGE,
       V0, WACK, MERGE,
       VB, WACK, ITCB,  // verify merged byte and return it if acked ok 
-      FAIL };          // verification failed
+      CALLFAIL };          // verification failed
 
 
 const ackOp FLASH LOCO_ID_PROG[] = {
@@ -467,7 +467,7 @@ const ackOp FLASH LOCO_ID_PROG[] = {
       V0, WACK, MERGE,
       V0, WACK, MERGE,
       VB, WACK, ITCB,  // verify merged byte and callback
-      FAIL
+      CALLFAIL
       };    
 
 const ackOp FLASH SHORT_LOCO_ID_PROG[] = {
@@ -484,7 +484,7 @@ const ackOp FLASH SHORT_LOCO_ID_PROG[] = {
       SETBYTEL,   // low byte of word 
       WB,WACK,    // some decoders don't ACK writes
       VB,WACK,ITCB,
-      FAIL
+      CALLFAIL
 };    
 
 const ackOp FLASH LONG_LOCO_ID_PROG[] = {
@@ -508,7 +508,7 @@ const ackOp FLASH LONG_LOCO_ID_PROG[] = {
       SETBYTEL,   // low byte of word 
       WB,WACK,
       VB,WACK,ITC1,   // callback(1) means Ok
-      FAIL
+      CALLFAIL
 };    
 
 void  DCC::writeCVByte(int16_t cv, byte byteValue, ACK_CALLBACK callback)  {
@@ -857,7 +857,7 @@ void DCC::ackManagerLoop() {
           }
         break;
         
-      case FAIL:  // callback(-1)
+      case CALLFAIL:  // callback(-1)
            callback(-1);
            return;
 

DCC.h

@@ -41,7 +41,7 @@ enum ackOp : byte
   ITCBV,            // If True callback(byte) - end of Verify Byte
   ITCB7,            // If True callback(byte &0x7F)
   NAKFAIL,          // if false callback(-1)
-  FAIL,             // callback(-1)
+  CALLFAIL,         // callback(-1)
   BIV,              // Set ackManagerByte to initial value for Verify retry
   STARTMERGE,       // Clear bit and byte settings ready for merge pass
   MERGE,            // Merge previous wack response with byte value and decrement bit number (use for readimng CV bytes)
@@ -207,6 +207,10 @@ private:
 #define ARDUINO_TYPE "TEENSY40"
 #elif defined(ARDUINO_TEENSY41)
 #define ARDUINO_TYPE "TEENSY41"
+#elif defined(ARDUINO_ARCH_ESP8266)
+#define ARDUINO_TYPE "ESP8266"
+#elif defined(ARDUINO_ARCH_ESP32)
+#define ARDUINO_TYPE "ESP32"
 #else
 #error CANNOT COMPILE - DCC++ EX ONLY WORKS WITH AN ARDUINO UNO, NANO 328, OR ARDUINO MEGA 1280/2560
 #endif

DCCEX.h

@@ -30,7 +30,13 @@
 #include "DIAG.h"
 #include "DCCEXParser.h"
 #include "version.h"
+#if defined(ARDUINO_ARCH_ESP8266)
+#include "WifiESP8266.h"
+#elif defined(ARDUINO_ARCH_ESP32)
+#include "WifiESP32.h"
+#else
 #include "WifiInterface.h"
+#endif
 #if ETHERNET_ON == true
 #include "EthernetInterface.h"
 #endif
@@ -43,5 +49,10 @@
 #include "Outputs.h"
 #include "RMFT.h"
 
+// not yet in this branch
+//#if __has_include ( "myAutomation.h")
+//  #include "RMFT.h"
+//  #define RMFT_ACTIVE
+//#endif
     
 #endif

DCCEXParser.cpp

@@ -17,9 +17,10 @@
  *  You should have received a copy of the GNU General Public License
  *  along with CommandStation.  If not, see <https://www.gnu.org/licenses/>.
  */
+#include "DCC.h" // includes "Motordriver.h" and <Arduino.h>
+#include "defines.h"
 #include "StringFormatter.h"
 #include "DCCEXParser.h"
-#include "DCC.h"
 #include "DCCWaveform.h"
 #include "Turnouts.h"
 #include "Outputs.h"
@@ -31,7 +32,9 @@
 
 #include "EEStore.h"
 #include "DIAG.h"
+#ifndef ESP_FAMILY
 #include <avr/wdt.h>
+#endif
 
 ////////////////////////////////////////////////////////////////////////////////
 //
@@ -860,8 +863,12 @@ bool DCCEXParser::parseD(Print *stream, int16_t params, int16_t p[])
 
     case HASH_KEYWORD_RESET:
         {
-          wdt_enable( WDTO_15MS); // set Arduino watchdog timer for 15ms 
+#ifndef ESP_FAMILY
-          delay(50);            // wait for the prescaller time to expire          
+          wdt_enable( WDTO_15MS); // set Arduino watchdog timer for 15ms
+          delay(50);              // wait for the prescaler time to expire
+#else
+	  /* XXX do right thing to reboot */
+#endif
           break; // and <X> if we didnt restart 
         }
         

DCCRMT.cpp

@@ -0,0 +1,168 @@
+/*
+ *  © 2021, Harald Barth.
+ *  
+ *  This file is part of DCC-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/>.
+ */
+
+#include "config.h"
+#include "defines.h"
+#include "DIAG.h"
+#include "DCCRMT.h"
+#include "DCCWaveform.h" // for MAX_PACKET_SIZE
+
+#define DATA_LEN(X) ((X)*9+1) // Each byte has one bit extra and we have one EOF marker
+
+#if ESP_IDF_VERSION < ESP_IDF_VERSION_VAL(4,2,0)
+#error wrong IDF version
+#endif
+
+void setDCCBit1(rmt_item32_t* item) {
+  item->level0    = 1;
+  item->duration0 = DCC_1_HALFPERIOD;
+  item->level1    = 0;
+  item->duration1 = DCC_1_HALFPERIOD;
+}
+
+void setDCCBit0(rmt_item32_t* item) {
+  item->level0    = 1;
+  item->duration0 = DCC_0_HALFPERIOD;
+  item->level1    = 0;
+  item->duration1 = DCC_0_HALFPERIOD;
+}
+
+// special long zero to trigger scope
+void setDCCBit0Long(rmt_item32_t* item) {
+  item->level0    = 1;
+  item->duration0 = DCC_0_HALFPERIOD + DCC_0_HALFPERIOD/10;
+  item->level1    = 0;
+  item->duration1 = DCC_0_HALFPERIOD + DCC_0_HALFPERIOD/10;
+}
+
+void setEOT(rmt_item32_t* item) {
+  item->val = 0;
+}
+
+void IRAM_ATTR interrupt(rmt_channel_t channel, void *t) {
+  RMTPin *tt = (RMTPin *)t;
+  tt->RMTinterrupt();
+}
+
+RMTPin::RMTPin(byte pin, byte ch, byte plen) {
+
+  // preamble
+  preambleLen = plen+2; // plen 1 bits, one 0 bit and one EOF marker
+  preamble = (rmt_item32_t*)malloc(preambleLen*sizeof(rmt_item32_t));
+  for (byte n=0; n<plen; n++)
+    setDCCBit1(preamble + n);      // preamble bits
+#ifdef SCOPE
+  setDCCBit0Long(preamble + plen); // start of packet 0 bit long version
+#else
+  setDCCBit0(preamble + plen);     // start of packet 0 bit normal version
+#endif
+  setEOT(preamble + plen + 1);     // EOT marker
+
+  // idle
+  idleLen = 28;
+  idle = (rmt_item32_t*)malloc(idleLen*sizeof(rmt_item32_t));
+  for (byte n=0; n<8; n++)   // 0 to 7
+    setDCCBit1(idle + n);
+  for (byte n=8; n<18; n++)  // 8, 9 to 16, 17
+    setDCCBit0(idle + n);
+  for (byte n=18; n<26; n++) // 18 to 25
+    setDCCBit1(idle + n);
+  setDCCBit1(idle + 26);     // end bit
+  setEOT(idle + 27);         // EOT marker
+
+  // data: max packet size today is 5 + checksum
+  maxDataLen = DATA_LEN(MAX_PACKET_SIZE);
+  data = (rmt_item32_t*)malloc(maxDataLen*sizeof(rmt_item32_t));
+  
+  rmt_config_t config;
+  // Configure the RMT channel for TX
+  bzero(&config, sizeof(rmt_config_t));
+  config.rmt_mode = RMT_MODE_TX;
+  config.channel = channel = (rmt_channel_t)ch;
+  config.clk_div = RMT_CLOCK_DIVIDER;
+  config.gpio_num = (gpio_num_t)pin;
+  config.mem_block_num = 2; // With longest DCC packet 11 inc checksum (future expansion)
+                            // number of bits needed is 22preamble + start +
+                            // 11*9 + extrazero + EOT = 124
+                            // 2 mem block of 64 RMT items should be enough
+
+  ESP_ERROR_CHECK(rmt_config(&config));
+  // NOTE: ESP_INTR_FLAG_IRAM is *NOT* included in this bitmask
+  ESP_ERROR_CHECK(rmt_driver_install(config.channel, 0, ESP_INTR_FLAG_LOWMED|ESP_INTR_FLAG_SHARED));
+
+  DIAG(F("Register interrupt on core %d"), xPortGetCoreID());
+
+  ESP_ERROR_CHECK(rmt_set_tx_loop_mode(channel, true));
+  rmt_register_tx_end_callback(interrupt, this);
+  rmt_set_tx_intr_en(channel, true);
+
+  DIAG(F("Starting channel %d signal generator"), config.channel);
+
+  // send one bit to kickstart the signal, remaining data will come from the
+  // packet queue. We intentionally do not wait for the RMT TX complete here.
+  //rmt_write_items(channel, preamble, preambleLen, false);
+  RMTprefill();
+  preambleNext = true;
+  dataReady = false;
+  RMTinterrupt();
+}
+
+void RMTPin::RMTprefill() {
+  rmt_fill_tx_items(channel, preamble, preambleLen, 0);
+  rmt_fill_tx_items(channel, idle, idleLen, preambleLen-1);
+}
+
+const byte transmitMask[] = {0x80, 0x40, 0x20, 0x10, 0x08, 0x04, 0x02, 0x01};
+
+bool RMTPin::RMTfillData(const byte buffer[], byte byteCount, byte repeatCount=1) {
+  if (dataReady == true || dataRepeat > 0) // we have still old work to do
+    return false;
+  if (DATA_LEN(byteCount) > maxDataLen)      // this would overun our allocated memory for data
+    return false;                      // something very broken, can not convert packet
+
+  // convert bytes to RMT stream of "bits"
+  byte bitcounter = 0;
+  for(byte n=0; n<byteCount; n++) {
+    for(byte bit=0; bit<8; bit++) {
+      if (buffer[n] & transmitMask[bit])
+	setDCCBit1(data + bitcounter++);
+      else
+	setDCCBit0(data + bitcounter++);
+    }
+    setDCCBit0(data + bitcounter++); // zero at end of each byte
+  }
+  setDCCBit1(data + bitcounter-1);     // overwrite previous zero bit with one bit
+  setEOT(data + bitcounter++);         // EOT marker
+  dataLen = bitcounter;
+  dataReady = true;
+  dataRepeat = repeatCount;
+  return true;
+}
+
+void IRAM_ATTR RMTPin::RMTinterrupt() {
+  //no rmt_tx_start(channel,true) as we run in loop mode
+  //preamble is always loaded at beginning of buffer
+  if (dataReady) {            // if we have new data, fill while preamble is running
+    rmt_fill_tx_items(channel, data, dataLen, preambleLen-1);
+    dataReady = false;
+  }
+  if (dataRepeat > 0)         // if a repeat count was specified, work on that
+    dataRepeat--;
+  return;
+}

DCCRMT.h

@@ -0,0 +1,57 @@
+/*
+ *  © 2021, Harald Barth.
+ *  
+ *  This file is part of DCC-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/>.
+ */
+
+#pragma once
+#include <Arduino.h>
+#include "driver/rmt.h"
+#include "soc/rmt_reg.h"
+#include "soc/rmt_struct.h"
+
+// make calculations easy and set up for microseconds
+#define RMT_CLOCK_DIVIDER 80
+#define DCC_1_HALFPERIOD 58  //4640 // 1 / 80000000 * 4640 = 58us
+#define DCC_0_HALFPERIOD 100 //8000
+
+class RMTPin {
+ public:
+  RMTPin(byte pin, byte ch, byte plen);
+  void IRAM_ATTR RMTinterrupt();
+  void RMTprefill();
+  bool RMTfillData(const byte buffer[], byte byteCount, byte repeatCount);
+  
+  static RMTPin mainRMTPin;
+  static RMTPin progRMTPin;
+  
+ private:
+    
+  rmt_channel_t channel;
+  // 3 types of data to send, preamble and then idle or data
+  // if this is prog track, idle will contain reset instead
+  rmt_item32_t *idle;
+  byte idleLen;
+  rmt_item32_t *preamble;
+  byte preambleLen;
+  rmt_item32_t *data;
+  byte dataLen;
+  byte maxDataLen;
+  // flags 
+  volatile bool preambleNext = true;  // alternate between preamble and content
+  volatile bool dataReady = false;    // do we have real data available or send idle
+  volatile byte dataRepeat = 0;
+};

DCCTimer.cpp

@@ -44,7 +44,7 @@
 
 #include "DCCTimer.h"
 const int DCC_SIGNAL_TIME=58;  // this is the 58uS DCC 1-bit waveform half-cycle 
-const long CLOCK_CYCLES=(F_CPU / 1000000 * DCC_SIGNAL_TIME) >>1;
+const long CLOCK_CYCLES=(F_CPU / 1000000 * DCC_SIGNAL_TIME);
 
 INTERRUPT_CALLBACK interruptHandler=0;
 
@@ -53,11 +53,11 @@ INTERRUPT_CALLBACK interruptHandler=0;
   
   void DCCTimer::begin(INTERRUPT_CALLBACK callback) {
     interruptHandler=callback;
-    noInterrupts(); 
+    noInterrupts();
     ADC0.CTRLC = (ADC0.CTRLC & 0b00110000) | 0b01000011;  // speed up analogRead sample time   
     TCB0.CTRLB = TCB_CNTMODE_INT_gc & ~TCB_CCMPEN_bm; // timer compare mode with output disabled
     TCB0.CTRLA = TCB_CLKSEL_CLKDIV2_gc; //   8 MHz ~ 0.125 us      
-    TCB0.CCMP =  CLOCK_CYCLES -1;  // 1 tick less for timer reset
+    TCB0.CCMP =  (CLOCK_CYCLES>>1) -1;  // 1 tick less for timer reset
     TCB0.INTFLAGS = TCB_CAPT_bm; // clear interrupt request flag
     TCB0.INTCTRL = TCB_CAPT_bm;  // Enable the interrupt
     TCB0.CNT = 0;
@@ -146,6 +146,50 @@ void DCCTimer::read(uint8_t word, uint8_t *mac, uint8_t offset) {
 }
 #endif
 
+#elif defined(ARDUINO_ARCH_ESP8266)
+
+void DCCTimer::begin(INTERRUPT_CALLBACK callback) {
+  interruptHandler=callback;
+  timer1_disable();
+
+  // There seem to be differnt ways to attach interrupt handler
+  //    ETS_FRC_TIMER1_INTR_ATTACH(NULL, NULL);
+  //    ETS_FRC_TIMER1_NMI_INTR_ATTACH(interruptHandler);
+  // Let us choose the one from the API
+  timer1_attachInterrupt(interruptHandler);
+
+  // not exactly sure of order:
+  timer1_enable(TIM_DIV1, TIM_EDGE, TIM_LOOP);
+  timer1_write(CLOCK_CYCLES);
+}
+// We do not support to use PWM to make the Waveform on ESP
+bool IRAM_ATTR DCCTimer::isPWMPin(byte pin) {
+  return false;
+}
+void IRAM_ATTR DCCTimer::setPWM(byte pin, bool high) {
+}
+
+#elif defined(ARDUINO_ARCH_ESP32)
+// https://www.visualmicro.com/page/Timer-Interrupts-Explained.aspx
+
+portMUX_TYPE timerMux = portMUX_INITIALIZER_UNLOCKED;
+
+void DCCTimer::begin(INTERRUPT_CALLBACK callback) {
+  interruptHandler = callback;
+  hw_timer_t *timer = NULL;
+  timer = timerBegin(0, 2, true); // prescaler can be 2 to 65536 so choose 2
+  timerAttachInterrupt(timer, interruptHandler, true);
+  timerAlarmWrite(timer, CLOCK_CYCLES / 6, true); // divide by prescaler*3 (Clockbase is 80Mhz and not F_CPU 240Mhz)
+  timerAlarmEnable(timer);
+}
+
+// We do not support to use PWM to make the Waveform on ESP
+bool IRAM_ATTR DCCTimer::isPWMPin(byte pin) {
+  return false;
+}
+void IRAM_ATTR DCCTimer::setPWM(byte pin, bool high) {
+}
+
 #else 
   // Arduino nano, uno, mega etc
 #if defined(__AVR_ATmega1280__) || defined(__AVR_ATmega2560__)
@@ -159,10 +203,10 @@ void DCCTimer::read(uint8_t word, uint8_t *mac, uint8_t offset) {
 
   void DCCTimer::begin(INTERRUPT_CALLBACK callback) {
     interruptHandler=callback;
-    noInterrupts();          
+    noInterrupts();
     ADCSRA = (ADCSRA & 0b11111000) | 0b00000100;   // speed up analogRead sample time 
     TCCR1A = 0;
-    ICR1 = CLOCK_CYCLES;
+    ICR1 = CLOCK_CYCLES>>1;
     TCNT1 = 0;   
     TCCR1B = _BV(WGM13) | _BV(CS10);     // Mode 8, clock select 1
     TIMSK1 = _BV(TOIE1); // Enable Software interrupt

DCCTimer.h

@@ -37,4 +37,14 @@ class DCCTimer {
   private:
 };
 
+#if defined(ARDUINO_ARCH_ESP32)
+extern portMUX_TYPE timerMux;
 #endif
+
+#if !(defined(ARDUINO_ARCH_ESP32) || defined(ARDUINO_ARCH_ESP8266))
+#ifndef IRAM_ATTR
+#define IRAM_ATTR
+#endif
+#endif
+
+#endif //DCCTimer.h

DCCWaveform.cpp

@@ -20,6 +20,7 @@
 
 #include <Arduino.h>
 
+#include "defines.h"
 #include "DCCWaveform.h"
 #include "DCCTimer.h"
 #include "DIAG.h"
@@ -36,6 +37,9 @@ volatile uint8_t DCCWaveform::numAckSamples=0;
 uint8_t DCCWaveform::trailingEdgeCounter=0;
 
 void DCCWaveform::begin(MotorDriver * mainDriver, MotorDriver * progDriver) {
+
+  mainTrack.rmtPin = new RMTPin(21, 0, PREAMBLE_BITS_MAIN);
+
   mainTrack.motorDriver=mainDriver;
   progTrack.motorDriver=progDriver;
   progTripValue = progDriver->mA2raw(TRIP_CURRENT_PROG); // need only calculate once hence static
@@ -51,33 +55,63 @@ void DCCWaveform::begin(MotorDriver * mainDriver, MotorDriver * progDriver) {
   DCCTimer::begin(DCCWaveform::interruptHandler);     
 }
 
-void DCCWaveform::loop(bool ackManagerActive) {
+#ifdef SLOW_ANALOG_READ
-  mainTrack.checkPowerOverload(false);
+// Flag to hold if we need to run ack checking in loop
+volatile bool ackflag = 0;
+#endif
+
+void IRAM_ATTR DCCWaveform::loop(bool ackManagerActive) {
+
+  if (mainTrack.packetPendingRMT) {
+    mainTrack.rmtPin->RMTfillData(mainTrack.pendingPacket, mainTrack.pendingLength, mainTrack.pendingRepeats);
+    mainTrack.packetPendingRMT=false;
+    // sentResetsSincePacket = 0 // later when progtrack
+  }
+
+#ifdef SLOW_ANALOG_READ
+  if (ackflag) {
+    progTrack.checkAck();
+    // reset flag AFTER check is done
+    portENTER_CRITICAL(&timerMux);
+    ackflag = 0;
+    portEXIT_CRITICAL(&timerMux);
+  } else {
+    progTrack.checkPowerOverload(ackManagerActive);
+  }
+#else
   progTrack.checkPowerOverload(ackManagerActive);
+#endif
+  mainTrack.checkPowerOverload(false);
 }
 
 #pragma GCC push_options
 #pragma GCC optimize ("-O3")
-void DCCWaveform::interruptHandler() {
+void IRAM_ATTR DCCWaveform::interruptHandler() {
   // call the timer edge sensitive actions for progtrack and maintrack
   // member functions would be cleaner but have more overhead
   byte sigMain=signalTransform[mainTrack.state];
   byte sigProg=progTrackSyncMain? sigMain : signalTransform[progTrack.state];
-  
   // Set the signal state for both tracks
   mainTrack.motorDriver->setSignal(sigMain);
   progTrack.motorDriver->setSignal(sigProg);
-  
   // Move on in the state engine
   mainTrack.state=stateTransform[mainTrack.state];    
   progTrack.state=stateTransform[progTrack.state];    
-
-
   // WAVE_PENDING means we dont yet know what the next bit is
-  if (mainTrack.state==WAVE_PENDING) mainTrack.interrupt2();  
+  if (mainTrack.state==WAVE_PENDING)
-  if (progTrack.state==WAVE_PENDING) progTrack.interrupt2();
+    mainTrack.interrupt2();
-  else if (progTrack.ackPending) progTrack.checkAck();
+  if (progTrack.state==WAVE_PENDING)
-
+    progTrack.interrupt2();
+#ifdef SLOW_ANALOG_READ
+  else if (progTrack.ackPending && ackflag == 0) { // We need AND we are not already checking
+    portENTER_CRITICAL(&timerMux);
+    ackflag = 1;
+    portEXIT_CRITICAL(&timerMux);
+  }
+#else
+  else if (progTrack.ackPending)
+    progTrack.checkAck();
+#endif
 }
 #pragma GCC push_options
 
@@ -94,6 +128,7 @@ const byte bitMask[] = {0x00, 0x80, 0x40, 0x20, 0x10, 0x08, 0x04, 0x02, 0x01};
 DCCWaveform::DCCWaveform( byte preambleBits, bool isMain) {
   isMainTrack = isMain;
   packetPending = false;
+  packetPendingRMT = false;
   memcpy(transmitPacket, idlePacket, sizeof(idlePacket));
   state = WAVE_START;
   // The +1 below is to allow the preamble generator to create the stop bit
@@ -202,7 +237,7 @@ const bool DCCWaveform::signalTransform[]={
         
 #pragma GCC push_options
 #pragma GCC optimize ("-O3")
-void DCCWaveform::interrupt2() {
+void IRAM_ATTR DCCWaveform::interrupt2() {
   // calculate the next bit to be sent:
   // set state WAVE_MID_1  for a 1=bit
   //        or WAVE_HIGH_0 for a 0 bit.
@@ -212,7 +247,9 @@ void DCCWaveform::interrupt2() {
     remainingPreambles--;
     // Update free memory diagnostic as we don't have anything else to do this time.
     // Allow for checkAck and its called functions using 22 bytes more.
-    updateMinimumFreeMemory(22); 
+#ifndef ESP_FAMILY
+    updateMinimumFreeMemory(22);
+#endif
     return;
   }
 
@@ -237,7 +274,8 @@ void DCCWaveform::interrupt2() {
         transmitRepeats--;
       }
       else if (packetPending) {
-        // Copy pending packet to transmit packet
+	portENTER_CRITICAL(&timerMux);
+	// Copy pending packet to transmit packet
         // a fixed length memcpy is faster than a variable length loop for these small lengths
         // for (int b = 0; b < pendingLength; b++) transmitPacket[b] = pendingPacket[b];
         memcpy( transmitPacket, pendingPacket, sizeof(pendingPacket));
@@ -246,6 +284,7 @@ void DCCWaveform::interrupt2() {
         transmitRepeats = pendingRepeats;
         packetPending = false;
         sentResetsSincePacket=0;
+	portEXIT_CRITICAL(&timerMux);
       }
       else {
         // Fortunately reset and idle packets are the same length
@@ -264,7 +303,7 @@ void DCCWaveform::interrupt2() {
 void DCCWaveform::schedulePacket(const byte buffer[], byte byteCount, byte repeats) {
   if (byteCount > MAX_PACKET_SIZE) return; // allow for chksum
   while (packetPending);
-
+  portENTER_CRITICAL(&timerMux);
   byte checksum = 0;
   for (byte b = 0; b < byteCount; b++) {
     checksum ^= buffer[b];
@@ -275,7 +314,9 @@ void DCCWaveform::schedulePacket(const byte buffer[], byte byteCount, byte repea
   pendingLength = byteCount + 1;
   pendingRepeats = repeats;
   packetPending = true;
+  packetPendingRMT = true;
   sentResetsSincePacket=0;
+  portEXIT_CRITICAL(&timerMux);
 }
 
 // Operations applicable to PROG track ONLY.
@@ -313,14 +354,14 @@ byte DCCWaveform::getAck() {
 
 #pragma GCC push_options
 #pragma GCC optimize ("-O3")
-void DCCWaveform::checkAck() {
+void IRAM_ATTR DCCWaveform::checkAck() {
     // This function operates in interrupt() time so must be fast and can't DIAG 
     if (sentResetsSincePacket > 6) {  //ACK timeout
         ackCheckDuration=millis()-ackCheckStart;
         ackPending = false;
         return; 
     }
-      
+
     int current=motorDriver->getCurrentRaw();
     numAckSamples++;
     if (current > ackMaxCurrent) ackMaxCurrent=current;

DCCWaveform.h

@@ -20,6 +20,7 @@
 #ifndef DCCWaveform_h
 #define DCCWaveform_h
 
+#include "DCCRMT.h"
 #include "MotorDriver.h"
 
 // Wait times for power management. Unit: milliseconds
@@ -82,6 +83,7 @@ class DCCWaveform {
     }
     void schedulePacket(const byte buffer[], byte byteCount, byte repeats);
     volatile bool packetPending;
+    volatile bool packetPendingRMT;
     volatile byte sentResetsSincePacket;
     volatile bool autoPowerOff=false;
     void setAckBaseline();  //prog track only
@@ -122,6 +124,7 @@ class DCCWaveform {
     
     bool isMainTrack;
     MotorDriver*  motorDriver;
+    RMTPin* rmtPin;
     // Transmission controller
     byte transmitPacket[MAX_PACKET_SIZE+1]; // +1 for checksum
     byte transmitLength;

GITHUB_SHA.h

@@ -1 +1 @@
-#define GITHUB_SHA "ee5db61"
+#define GITHUB_SHA "ESP32-2021120-11:30"

IO_MCP23008.h

@@ -22,6 +22,12 @@
 
 #include "IO_GPIOBase.h"
 
+#if defined(ARDUINO_ARCH_ESP32) // min seems to be missing from that package
+#ifndef min
+#define min(a,b) ((a)<(b)?(a):(b))
+#endif
+#endif
+
 class MCP23008 : public GPIOBase<uint8_t> {
 public:
   static void create(VPIN firstVpin, uint8_t nPins, uint8_t I2CAddress, int interruptPin=-1) {
@@ -97,4 +103,4 @@ private:
 
 };
 
-#endif
+#endif

IO_PCF8574.h

@@ -75,7 +75,7 @@ private:
     if (immediate) {
       uint8_t buffer[1];
       I2CManager.read(_I2CAddress, buffer, 1);
-      _portInputState = ((uint16_t)buffer) & 0xff;
+      _portInputState = buffer[0];
     } else {
       requestBlock.wait(); // Wait for preceding operation to complete
       // Issue new request to read GPIO register
@@ -86,7 +86,7 @@ private:
   // This function is invoked when an I/O operation on the requestBlock completes.
   void _processCompletion(uint8_t status) override {
     if (status == I2C_STATUS_OK) 
-      _portInputState = ((uint16_t)inputBuffer[0]) & 0xff;
+      _portInputState = inputBuffer[0];
     else  
       _portInputState = 0xff; 
   }
@@ -99,4 +99,4 @@ private:
   uint8_t inputBuffer[1];
 };
 
-#endif
+#endif

MotorDriver.cpp

@@ -20,11 +20,10 @@
 #include "MotorDriver.h"
 #include "DCCTimer.h"
 #include "DIAG.h"
-
+#if defined(ARDUINO_ARCH_ESP32)
-#define setHIGH(fastpin)  *fastpin.inout |= fastpin.maskHIGH
+#include <driver/adc.h>
-#define setLOW(fastpin)   *fastpin.inout &= fastpin.maskLOW
+#define pinToADC1Channel(X) (adc1_channel_t)(((X) > 35) ? (X)-36 : (X)-28)
-#define isHIGH(fastpin)   (*fastpin.inout & fastpin.maskHIGH)
+#endif
-#define isLOW(fastpin)    (!isHIGH(fastpin))
 
 bool MotorDriver::usePWM=false;
 bool MotorDriver::commonFaultPin=false;
@@ -59,8 +58,15 @@ MotorDriver::MotorDriver(byte power_pin, byte signal_pin, byte signal_pin2, int8
   
   currentPin=current_pin;
   if (currentPin!=UNUSED_PIN) {
+#if defined(ARDUINO_ARCH_ESP32)
+    pinMode(currentPin, ANALOG);
+    adc1_config_width(ADC_WIDTH_BIT_12);
+    adc1_config_channel_atten(pinToADC1Channel(currentPin),ADC_ATTEN_DB_11);
+    senseOffset = adc1_get_raw(pinToADC1Channel(currentPin));
+#else
     pinMode(currentPin, INPUT);
     senseOffset=analogRead(currentPin); // value of sensor at zero current
+#endif
   }
 
   faultPin=fault_pin;
@@ -110,7 +116,7 @@ void MotorDriver::setBrake(bool on) {
   else setLOW(fastBrakePin);
 }
 
-void MotorDriver::setSignal( bool high) {
+void IRAM_ATTR MotorDriver::setSignal( bool high) {
    if (usePWM) {
     DCCTimer::setPWM(signalPin,high);
    }
@@ -155,6 +161,8 @@ int MotorDriver::getCurrentRaw() {
   current = analogRead(currentPin)-senseOffset;
   overflow_count = 0;
   SREG = sreg_backup;    /* restore interrupt state */
+#elif defined(ARDUINO_ARCH_ESP32)
+  current = adc1_get_raw(pinToADC1Channel(currentPin))-senseOffset;
 #else
   current = analogRead(currentPin)-senseOffset;
 #endif
@@ -176,8 +184,8 @@ int MotorDriver::mA2raw( unsigned int mA) {
 
 void  MotorDriver::getFastPin(const FSH* type,int pin, bool input, FASTPIN & result) {
     // DIAG(F("MotorDriver %S Pin=%d,"),type,pin);
-    (void) type; // avoid compiler warning if diag not used above. 
+    (void) type; // avoid compiler warning if diag not used above.
-    uint8_t port = digitalPinToPort(pin);
+    PORTTYPE port = digitalPinToPort(pin);
     if (input)
       result.inout = portInputRegister(port);
     else

MotorDriver.h

@@ -18,6 +18,7 @@
  */
 #ifndef MotorDriver_h
 #define MotorDriver_h
+#include "defines.h"
 #include "FSH.h"
 
 // Virtualised Motor shield 1-track hardware Interface
@@ -26,13 +27,15 @@
 #define UNUSED_PIN 127 // inside int8_t
 #endif
 
-#if defined(__IMXRT1062__)
+#if defined(__IMXRT1062__) || defined(ESP_FAMILY)
+typedef uint32_t PORTTYPE;
 struct FASTPIN {
   volatile uint32_t *inout;
   uint32_t maskHIGH;  
   uint32_t maskLOW;  
 };
 #else
+typedef uint8_t PORTTYPE;
 struct FASTPIN {
   volatile uint8_t *inout;
   uint8_t maskHIGH;  
@@ -40,12 +43,30 @@ struct FASTPIN {
 };
 #endif
 
+#define setHIGH(fastpin)  *fastpin.inout |= fastpin.maskHIGH
+#define setLOW(fastpin)   *fastpin.inout &= fastpin.maskLOW
+#define isHIGH(fastpin)   (*fastpin.inout & fastpin.maskHIGH)
+#define isLOW(fastpin)    (!isHIGH(fastpin))
+
 class MotorDriver {
   public:
     MotorDriver(byte power_pin, byte signal_pin, byte signal_pin2, int8_t brake_pin, 
                 byte current_pin, float senseFactor, unsigned int tripMilliamps, byte faultPin);
     virtual void setPower( bool on);
-    virtual void setSignal( bool high);
+    void setSignal( bool high);/* {
+      if (usePWM) {
+	DCCTimer::setPWM(signalPin,high);
+      }
+      
+      if (high) {
+        setHIGH(fastSignalPin);
+        if (dualSignal) setLOW(fastSignalPin2);
+      }
+      else {
+        setLOW(fastSignalPin);
+        if (dualSignal) setHIGH(fastSignalPin2);
+      }
+      };*/
     virtual void setBrake( bool on);
     virtual int  getCurrentRaw();
     virtual unsigned int raw2mA( int raw);

RMFTMacros.h

@@ -226,16 +226,16 @@ const int StringMacroTracker1=__COUNTER__;
 
 // Define macros for route code creation 
 #define V(val) ((int16_t)(val))&0x00FF,((int16_t)(val)>>8)&0x00FF
-#define NOP 0,0
+#define NOOPERAND 0,0
 
 #define ALIAS(name,value) 
 #define EXRAIL const  FLASH  byte RMFT2::RouteCode[] = {
 #define AUTOMATION(id, description)  OPCODE_AUTOMATION, V(id), 
 #define ROUTE(id, description)  OPCODE_ROUTE, V(id), 
 #define SEQUENCE(id)  OPCODE_SEQUENCE, V(id), 
-#define ENDTASK OPCODE_ENDTASK,NOP,
+#define ENDTASK OPCODE_ENDTASK,NOOPERAND,
-#define DONE OPCODE_ENDTASK,NOP,
+#define DONE OPCODE_ENDTASK,NOOPERAND,
-#define ENDEXRAIL OPCODE_ENDTASK,NOP,OPCODE_ENDEXRAIL,NOP };
+#define ENDEXRAIL OPCODE_ENDTASK,NOOPERAND,OPCODE_ENDEXRAIL,NOOPERAND };
  
 #define AFTER(sensor_id) OPCODE_AT,V(sensor_id),OPCODE_AFTER,V(sensor_id),
 #define AMBER(signal_id) OPCODE_AMBER,V(signal_id),
@@ -245,7 +245,7 @@ const int StringMacroTracker1=__COUNTER__;
 #define DELAY(ms) OPCODE_DELAY,V(ms/100L),
 #define DELAYMINS(mindelay) OPCODE_DELAYMINS,V(mindelay),
 #define DELAYRANDOM(mindelay,maxdelay) OPCODE_DELAY,V(mindelay/100L),OPCODE_RANDWAIT,V((maxdelay-mindelay)/100L),
-#define ENDIF  OPCODE_ENDIF,NOP,
+#define ENDIF  OPCODE_ENDIF,NOOPERAND,
 #define ESTOP OPCODE_SPEED,V(1), 
 #define FADE(pin,value,ms) OPCODE_SERVO,V(pin),OPCODE_PAD,V(value),OPCODE_PAD,V(PCA9685::ProfileType::UseDuration|PCA9685::NoPowerOff),OPCODE_PAD,V(ms/100L),
 #define FOFF(func) OPCODE_FOFF,V(func),
@@ -258,23 +258,23 @@ const int StringMacroTracker1=__COUNTER__;
 #define IFNOT(sensor_id) OPCODE_IFNOT,V(sensor_id),
 #define IFRANDOM(percent) OPCODE_IFRANDOM,V(percent),
 #define IFRESERVE(block) OPCODE_IFRESERVE,V(block),
-#define INVERT_DIRECTION OPCODE_INVERT_DIRECTION,NOP,
+#define INVERT_DIRECTION OPCODE_INVERT_DIRECTION,NOOPERAND,
-#define JOIN OPCODE_JOIN,NOP,
+#define JOIN OPCODE_JOIN,NOOPERAND,
 #define LATCH(sensor_id) OPCODE_LATCH,V(sensor_id),
 #define LCD(id,msg) PRINT(msg)
 #define LCN(msg) PRINT(msg)
 #define ONCLOSE(turnout_id) OPCODE_ONCLOSE,V(turnout_id),
 #define ONTHROW(turnout_id) OPCODE_ONTHROW,V(turnout_id),
-#define PAUSE OPCODE_PAUSE,NOP,
+#define PAUSE OPCODE_PAUSE,NOOPERAND,
 #define POM(cv,value) OPCODE_POM,V(cv),OPCODE_PAD,V(value),
-#define POWEROFF OPCODE_POWEROFF,NOP,
+#define POWEROFF OPCODE_POWEROFF,NOOPERAND,
 #define PRINT(msg) OPCODE_PRINT,V(__COUNTER__ - StringMacroTracker2),
-#define READ_LOCO OPCODE_READ_LOCO1,NOP,OPCODE_READ_LOCO2,NOP,
+#define READ_LOCO OPCODE_READ_LOCO1,NOOPERAND,OPCODE_READ_LOCO2,NOOPERAND,
 #define RED(signal_id) OPCODE_RED,V(signal_id),
 #define RESERVE(blockid) OPCODE_RESERVE,V(blockid),
 #define RESET(pin) OPCODE_RESET,V(pin),
-#define RESUME OPCODE_RESUME,NOP,
+#define RESUME OPCODE_RESUME,NOOPERAND,
-#define RETURN OPCODE_RETURN,NOP,
+#define RETURN OPCODE_RETURN,NOOPERAND,
 #define REV(speed) OPCODE_REV,V(speed),
 #define SENDLOCO(cab,route) OPCODE_SENDLOCO,V(cab),OPCODE_PAD,V(route),
 #define SERIAL(msg) PRINT(msg)
@@ -293,7 +293,7 @@ const int StringMacroTracker1=__COUNTER__;
 #define PIN_TURNOUT(id,pin) OPCODE_PINTURNOUT,V(id),OPCODE_PAD,V(pin), 
 #define THROW(id)  OPCODE_THROW,V(id),
 #define TURNOUT(id,addr,subaddr) OPCODE_TURNOUT,V(id),OPCODE_PAD,V(addr),OPCODE_PAD,V(subaddr),
-#define UNJOIN OPCODE_UNJOIN,NOP,
+#define UNJOIN OPCODE_UNJOIN,NOOPERAND,
 #define UNLATCH(sensor_id) OPCODE_UNLATCH,V(sensor_id),
 #define WAITFOR(pin) OPCODE_WAITFOR,V(pin),
 #define XFOFF(cab,func) OPCODE_XFOFF,V(cab),OPCODE_PAD,V(func),

RingStream.cpp

@@ -18,6 +18,7 @@
  */
 
 #include "RingStream.h"
+#include "defines.h"
 #include "DIAG.h"
 
 RingStream::RingStream( const uint16_t len)
@@ -30,27 +31,36 @@ RingStream::RingStream( const uint16_t len)
   _overflow=false;
   _mark=0;
   _count=0; 
+#if defined(ARDUINO_ARCH_ESP32)
+  _bufMux = portMUX_INITIALIZER_UNLOCKED;
+#endif
 }
 
 size_t RingStream::write(uint8_t b) {
   if (_overflow) return 0;
+  portENTER_CRITICAL(&_bufMux);
   _buffer[_pos_write] = b;
   ++_pos_write;
   if (_pos_write==_len) _pos_write=0;
   if (_pos_write==_pos_read) {
     _overflow=true; 
+    portEXIT_CRITICAL(&_bufMux);
     return 0;
   }
   _count++;
+  portEXIT_CRITICAL(&_bufMux);
   return 1;
 }
 
-int RingStream::read() {
+int RingStream::read(byte advance) {
-  if ((_pos_read==_pos_write) && !_overflow) return -1;  // empty  
+  if ((_pos_read==_pos_write) && !_overflow) return -1;  // empty
+  if (_pos_read == _mark) return -1;
+  portENTER_CRITICAL(&_bufMux);
   byte b=_buffer[_pos_read];
-  _pos_read++;
+  _pos_read += advance;
   if (_pos_read==_len) _pos_read=0;
   _overflow=false;
+  portEXIT_CRITICAL(&_bufMux);
   return b;
 }
 
@@ -68,11 +78,14 @@ int RingStream::freeSpace() {
 
 // mark start of message with client id (0...9)
 void RingStream::mark(uint8_t b) {
+    //DIAG(F("Mark1 len=%d count=%d pr=%d pw=%d m=%d"),_len, _count,_pos_read,_pos_write,_mark);
+    portENTER_CRITICAL(&_bufMux);
     _mark=_pos_write;
     write(b); // client id
     write((uint8_t)0);  // count MSB placemarker
     write((uint8_t)0);  // count LSB placemarker
     _count=0;
+    portEXIT_CRITICAL(&_bufMux);
 }
 
 // peekTargetMark is used by the parser stash routines to know which client
@@ -81,17 +94,25 @@ uint8_t RingStream::peekTargetMark() {
   return _buffer[_mark];
 }
 
+void RingStream::info() {
+  DIAG(F("Info len=%d count=%d pr=%d pw=%d m=%d"),_len, _count,_pos_read,_pos_write,_mark);
+}
+
 bool RingStream::commit() {
+  //DIAG(F("Commit1 len=%d count=%d pr=%d pw=%d m=%d"),_len, _count,_pos_read,_pos_write,_mark);
+  portENTER_CRITICAL(&_bufMux);
   if (_overflow) {
         DIAG(F("RingStream(%d) commit(%d) OVERFLOW"),_len, _count);
         // just throw it away 
         _pos_write=_mark;
         _overflow=false;
-        return false; // commit failed
+	portEXIT_CRITICAL(&_bufMux);
+	return false; // commit failed
   }
   if (_count==0) {
     // ignore empty response 
     _pos_write=_mark;
+    portEXIT_CRITICAL(&_bufMux);
     return true; // true=commit ok
   }
   // Go back to the _mark and inject the count 1 byte later
@@ -101,5 +122,8 @@ bool RingStream::commit() {
   _mark++;
   if (_mark==_len) _mark=0;
   _buffer[_mark]=lowByte(_count);
+  _mark=_len+1;
+  //DIAG(F("Commit2 len=%d count=%d pr=%d pw=%d m=%d"),_len, _count,_pos_read,_pos_write,_mark);
+  portEXIT_CRITICAL(&_bufMux);
   return true; // commit worked
 }

RingStream.h

@@ -28,14 +28,17 @@ class RingStream : public Print {
   
     virtual size_t write(uint8_t b);
     using Print::write;
-    int read();
+    inline int read() { return read(1); };
+    inline int peek() { return read(0); };
     int count();
     int freeSpace();
     void mark(uint8_t b);
     bool commit();
     uint8_t peekTargetMark();
-    
+    void info();
+
  private:
+   int read(byte advance);
    int _len;
    int _pos_write;
    int _pos_read;
@@ -43,6 +46,9 @@ class RingStream : public Print {
    int _mark;
    int _count;
    byte * _buffer;
+#if defined(ARDUINO_ARCH_ESP32)
+   portMUX_TYPE _bufMux;
+#endif
 };
 
 #endif

WifiESP32.cpp

@@ -0,0 +1,246 @@
+/*
+    © 2021, Harald Barth.
+
+    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/>.
+*/
+
+#include <vector>
+#include "defines.h"
+#if defined(ARDUINO_ARCH_ESP32)
+#include <WiFi.h>
+#include "WifiESP32.h"
+#include "DIAG.h"
+#include "RingStream.h"
+#include "CommandDistributor.h"
+/*
+#include "soc/rtc_wdt.h"
+#include "esp_task_wdt.h"
+*/
+
+#include "soc/timer_group_struct.h"
+#include "soc/timer_group_reg.h"
+void feedTheDog0(){
+  // feed dog 0
+  TIMERG0.wdt_wprotect=TIMG_WDT_WKEY_VALUE; // write enable
+  TIMERG0.wdt_feed=1;                       // feed dog
+  TIMERG0.wdt_wprotect=0;                   // write protect
+  // feed dog 1
+  //TIMERG1.wdt_wprotect=TIMG_WDT_WKEY_VALUE; // write enable
+  //TIMERG1.wdt_feed=1;                       // feed dog
+  //TIMERG1.wdt_wprotect=0;                   // write protect
+}
+
+/*
+void enableCoreWDT(byte core){
+  TaskHandle_t idle = xTaskGetIdleTaskHandleForCPU(core);
+  if(idle == NULL){
+    DIAG(F("Get idle rask on core %d failed"),core);
+  } else {
+    if(esp_task_wdt_add(idle) != ESP_OK){
+      DIAG(F("Failed to add Core %d IDLE task to WDT"),core);
+    } else {
+      DIAG(F("Added Core %d IDLE task to WDT"),core);
+    }
+  }
+}
+
+void disableCoreWDT(byte core){
+    TaskHandle_t idle = xTaskGetIdleTaskHandleForCPU(core);
+    if(idle == NULL || esp_task_wdt_delete(idle) != ESP_OK){
+      DIAG(F("Failed to remove Core %d IDLE task from WDT"),core);
+    }
+}
+*/
+
+static std::vector<WiFiClient> clients; // a list to hold all clients
+static WiFiServer *server = NULL;
+static RingStream *outboundRing = new RingStream(2048);
+static bool APmode = false;
+
+void wifiLoop(void *){
+  for(;;){
+    WifiESP::loop();
+  }
+}
+
+bool WifiESP::setup(const char *SSid,
+                    const char *password,
+                    const char *hostname,
+                    int port,
+                    const byte channel) {
+  bool havePassword = true;
+  bool haveSSID = true;
+  bool wifiUp = false;
+  uint8_t tries = 40;
+
+  // tests
+  //  enableCoreWDT(1);
+  //  disableCoreWDT(0);
+
+  const char *yourNetwork = "Your network ";
+  if (strncmp(yourNetwork, SSid, 13) == 0 || strncmp("", SSid, 13) == 0)
+    haveSSID = false;
+  if (strncmp(yourNetwork, password, 13) == 0 || strncmp("", password, 13) == 0)
+    havePassword = false;
+
+  if (haveSSID && havePassword) {
+    WiFi.mode(WIFI_STA);
+    WiFi.setAutoReconnect(true);
+    WiFi.begin(SSid, password);
+    while (WiFi.status() != WL_CONNECTED && tries) {
+      Serial.print('.');
+      tries--;
+      delay(500);
+    }
+    if (WiFi.status() == WL_CONNECTED) {
+      DIAG(F("Wifi STA IP %s"),WiFi.localIP().toString().c_str());
+      wifiUp = true;
+    } else {
+      DIAG(F("Could not connect to Wifi SSID %s"),SSid);
+    }
+  }
+  if (!haveSSID) {
+    // prepare all strings
+    String strSSID("DCC_");
+    String strPass("PASS_");
+    String strMac = WiFi.macAddress();
+    strMac.remove(0,9);
+    strMac.replace(":","");
+    strMac.replace(":","");
+    strSSID.concat(strMac);
+    strPass.concat(strMac);
+
+    WiFi.mode(WIFI_AP);
+    if (WiFi.softAP(strSSID.c_str(),
+		    havePassword ? password : strPass.c_str(),
+		    channel, false, 8)) {
+      DIAG(F("Wifi AP SSID %s PASS %s"),strSSID.c_str(),havePassword ? password : strPass.c_str());
+      DIAG(F("Wifi AP IP %s"),WiFi.softAPIP().toString().c_str());
+      wifiUp = true;
+      APmode = true;
+    } else {
+      DIAG(F("Could not set up AP with Wifi SSID %s"),strSSID.c_str());
+    }
+  }
+
+
+  if (!wifiUp) {
+    DIAG(F("Wifi setup all fail (STA and AP mode)"));
+    // no idea to go on
+    return false;
+  }
+  server = new WiFiServer(port); // start listening on tcp port
+  server->begin();
+  // server started here
+
+  //start loop task
+  if (pdPASS != xTaskCreatePinnedToCore(
+	wifiLoop, /* Task function. */
+	"wifiLoop",/* name of task.  */
+	10000,     /* Stack size of task */
+	NULL,      /* parameter of the task */
+	1,         /* priority of the task */
+	NULL,      /* Task handle to keep track of created task */
+	0)) {      /* pin task to core 0 */
+    DIAG(F("Could not create wifiLoop task"));
+    return false;
+  }
+
+  // report server started after wifiLoop creation
+  // when everything looks good
+  DIAG(F("Server up port %d"),port);
+  return true;
+}
+
+void WifiESP::loop() {
+  int clientId; //tmp loop var
+
+  // really no good way to check for LISTEN especially in AP mode?
+  if (APmode || WiFi.status() == WL_CONNECTED) {
+    if (server->hasClient()) {
+      // loop over all clients and remove inactive
+      for (clientId=0; clientId<clients.size(); clientId++){
+	// check if client is there and alive
+	if(!clients[clientId].connected()) {
+	  clients[clientId].stop();
+	  clients.erase(clients.begin()+clientId);
+	}
+      }
+      WiFiClient client;
+      while (client = server->available()) {
+	clients.push_back(client);
+	DIAG(F("New client %s"), client.remoteIP().toString().c_str());
+      }
+    }
+    // loop over all connected clients
+    for (clientId=0; clientId<clients.size(); clientId++){
+      if(clients[clientId].connected()) {
+	int len;
+	if ((len = clients[clientId].available()) > 0) {
+	  // read data from client
+	  byte cmd[len+1];
+	  for(int i=0; i<len; i++) {
+	    cmd[i]=clients[clientId].read();
+	  }
+	  cmd[len]=0;
+	  outboundRing->mark(clientId);
+	  CommandDistributor::parse(clientId,cmd,outboundRing);
+	  outboundRing->commit();
+	}
+      }
+    } // all clients
+
+    // something to write out?
+    clientId=outboundRing->peek();
+    if (clientId >= 0) {
+      if ((unsigned int)clientId > clients.size()) {
+	// something is wrong with the ringbuffer position
+	outboundRing->info();
+      } else {
+	// we have data to send in outboundRing
+	if(clients[clientId].connected()) {
+	  outboundRing->read(); // read over peek()
+	  int count=outboundRing->count();
+	  {
+	    char buffer[count+1];
+	    for(int i=0;i<count;i++) {
+	      int c = outboundRing->read();
+	      if (c >= 0)
+		buffer[i] = (char)c;
+	      else {
+		DIAG(F("Ringread fail at %d"),i);
+		break;
+	      }
+	    }
+	    buffer[count]=0;
+	    clients[clientId].write(buffer,count);
+	  }
+	}
+      }
+    }
+  } //connected
+
+  // when loop() is running on core0 we must
+  // feed the core0 wdt ourselves as yield()
+  // is not necessarily yielding to a low
+  // prio task. On core1 this is not a problem
+  // as there the wdt is disabled by the
+  // arduio IDE startup routines.
+  if (xPortGetCoreID() == 0)
+    feedTheDog0();
+  yield();
+}
+#endif //ESP32

WifiESP32.h

@@ -0,0 +1,39 @@
+/*
+ *  © 2021, Harald Barth.
+ *
+ *  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/>.
+ */
+
+#if defined(ARDUINO_ARCH_ESP32)
+#ifndef WifiESP32_h
+#define WifiESP32_h
+
+#include "FSH.h"
+
+class WifiESP
+{
+
+public:
+  static bool setup(const char *wifiESSID,
+		    const char *wifiPassword,
+		    const char *hostname,
+		    const int port,
+		    const byte channel);
+  static void loop();
+private:
+};
+#endif //WifiESP8266_h
+#endif //ESP8266

WifiESP8266.cpp

@@ -0,0 +1,270 @@
+/*
+    © 2021, Harald Barth.
+
+    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/>.
+*/
+
+#include "defines.h"
+#if defined(ARDUINO_ARCH_ESP8266)
+#include <ESP8266WiFi.h>
+#include <ESPAsyncTCP.h>
+#include <vector>
+#include <string>
+
+#include "WifiESP8266.h"
+#include "DIAG.h"
+#include "RingStream.h"
+#include "CommandDistributor.h"
+#include <string.h>
+
+static std::vector<AsyncClient*> clients; // a list to hold all clients
+static AsyncServer *server;
+
+static RingStream *outboundRing = new RingStream(2048);
+
+static void handleError(void* arg, AsyncClient* client, int8_t error) {
+  (void)arg;
+  DIAG(F("connection error %s from client %s"), client->errorToString(error), client->remoteIP().toString().c_str());
+}
+
+static void handleData(void* arg, AsyncClient* client, void *data, size_t len) {
+  (void)arg;
+  //DIAG(F("data received from client %s"), client->remoteIP().toString().c_str());
+  uint8_t clientId;
+  for (clientId=0; clientId<clients.size(); clientId++){
+    if (clients[clientId] == client) break;
+  }
+  if (clientId < clients.size()) {
+    byte cmd[len+1];
+    memcpy(cmd,data,len);
+    cmd[len]=0;
+    outboundRing->mark(clientId);
+    CommandDistributor::parse(clientId,cmd,outboundRing);
+    outboundRing->commit();
+  }
+}
+
+//static AsyncClient *debugclient = NULL;
+
+bool sendData(AsyncClient *client, char* data, size_t count) {
+  size_t willsend = 0;
+
+  // reply to client
+  if (client->canSend()) {
+    while (count > 0) {
+      if (client->connected())
+	willsend = client->add(data, count); // add checks for space()
+      else
+	willsend = 0;
+      if (willsend < count) {
+	DIAG(F("Willsend %d of count %d"), willsend, count);
+      }
+      if (client->connected() && client->send()) {
+	count = count - willsend;
+	data = data + willsend;
+      } else {
+	DIAG(F("Could not send promised %d"), count);
+	return false;
+      }
+    }
+    // Did send all bytes we wanted
+    return true;
+  }
+  DIAG(F("Aborting: Busy or space=0"));
+  return false;
+}
+
+static void deleteClient(AsyncClient* client) {
+  uint8_t clientId;
+  for (clientId=0; clientId<clients.size(); clientId++){
+    if (clients[clientId] == client) break;
+  }
+  if (clientId < clients.size()) {
+    clients[clientId] = NULL;
+  }
+}
+static void handleDisconnect(void* arg, AsyncClient* client) {
+  (void)arg;
+  DIAG(F("Client disconnected"));
+  deleteClient(client);
+}
+
+static void handleTimeOut(void* arg, AsyncClient* client, uint32_t time) {
+  (void)arg;
+  (void)time;
+  DIAG(F("client ACK timeout ip: %s"), client->remoteIP().toString().c_str());
+  deleteClient(client);
+}
+
+
+static void handleNewClient(void* arg, AsyncClient* client) {
+  (void)arg;
+  DIAG(F("New client %s"), client->remoteIP().toString().c_str());
+
+  // add to list
+  clients.push_back(client);
+
+  // register events
+  client->onData(&handleData, NULL);
+  client->onError(&handleError, NULL);
+  client->onDisconnect(&handleDisconnect, NULL);
+  client->onTimeout(&handleTimeOut, NULL);
+
+}
+
+/*  Things one _might_ want to do:
+   Disable soft watchdog: ESP.wdtDisable()
+   Enable  soft watchdog: ESP.wdtEnable(X) ignores the value of X and enables it for fixed
+                          time at least in version 3.0.2 of the esp8266 package.
+
+Internet says:
+
+I manage to complety disable the hardware watchdog on ESP8266 in order to run the benchmark CoreMark. 
+
+void hw_wdt_disable(){
+  *((volatile uint32_t*) 0x60000900) &= ~(1); // Hardware WDT OFF
+}
+
+void hw_wdt_enable(){
+  *((volatile uint32_t*) 0x60000900) |= 1; // Hardware WDT ON
+}
+
+*/
+
+bool WifiESP::setup(const char *SSid,
+                    const char *password,
+                    const char *hostname,
+                    int port,
+                    const byte channel) {
+  bool havePassword = true;
+  bool haveSSID = true;
+  bool wifiUp = false;
+
+  // We are server and should not sleep
+  wifi_set_sleep_type(NONE_SLEEP_T);
+  // connects to access point
+
+  const char *yourNetwork = "Your network ";
+  if (strncmp(yourNetwork, SSid, 13) == 0 || strncmp("", SSid, 13) == 0)
+    haveSSID = false;
+  if (strncmp(yourNetwork, password, 13) == 0 || strncmp("", password, 13) == 0)
+    havePassword = false;
+  
+  if (haveSSID && havePassword) {
+    WiFi.mode(WIFI_STA);
+    WiFi.setAutoReconnect(true);
+    WiFi.begin(SSid, password);
+    while (WiFi.status() != WL_CONNECTED) {
+      Serial.print('.');
+      delay(500);
+    }
+    if (WiFi.status() == WL_CONNECTED) {
+      DIAG(F("Wifi STA IP %s"),WiFi.localIP().toString().c_str());
+      wifiUp = true;
+    }
+  }
+  if (!haveSSID) {
+    // prepare all strings
+    String strSSID("DCC_");
+    String strPass("PASS_");
+    String strMac = WiFi.macAddress();
+    strMac.remove(0,9);
+    strMac.replace(":","");
+    strMac.replace(":","");
+    strSSID.concat(strMac);
+    strPass.concat(strMac);
+
+    WiFi.mode(WIFI_AP);
+    if (WiFi.softAP(strSSID.c_str(),
+		    havePassword ? password : strPass.c_str(),
+		    channel, false, 8)) {
+      DIAG(F("Wifi AP SSID %s PASS %s"),strSSID.c_str(),havePassword ? password : strPass.c_str());
+      DIAG(F("Wifi AP IP %s"),WiFi.softAPIP().toString().c_str());
+      wifiUp = true;
+    }
+  }
+
+
+  if (!wifiUp) {
+    DIAG(F("Wifi all fail"));
+    // no idea to go on
+    return false;
+  }
+
+  server = new AsyncServer(port); // start listening on tcp port
+
+  server->onClient(&handleNewClient, server);
+  server->begin();
+  DIAG(F("Server up port %d"),port);
+
+  return true;
+}
+
+void WifiESP::loop() {
+  AsyncClient *client = NULL;
+  // Do something with outboundRing
+  // call sendData
+  int clientId=outboundRing->peek();
+  if (clientId >= 0) {
+    if ((unsigned int)clientId > clients.size()) {
+      // something is wrong with the ringbuffer position
+      outboundRing->info();
+      client = NULL;
+    } else {
+      client = clients[clientId];
+    }
+//    if (client != debugclient) {
+//      DIAG(F("new client pointer = %x from id %d"), client, clientId);
+//      debugclient = client;
+//    }
+  } else {
+    client = NULL;
+  }
+  if (clientId>=0 && client && client->connected() && client->canSend()) {
+    outboundRing->read();
+    int count=outboundRing->count();
+    //DIAG(F("Wifi reply client=%d, count=%d"), clientId,count);
+    {
+      char buffer[count+1];
+      for(int i=0;i<count;i++) {
+	int c = outboundRing->read();
+	if (c >= 0)
+	  buffer[i] = (char)c;
+	else {
+	  DIAG(F("Ringread fail at %d"),i);
+	  break;
+	}
+      }
+      buffer[count]=0;
+      //DIAG(F("SEND:%s COUNT:%d"),buffer,count);
+      uint8_t tries = 3;
+      while (! sendData(client, buffer, count)) {
+	DIAG(F("senData fail"));
+	yield();
+	if (tries == 0) break;
+      }
+    }
+  }
+#ifdef ESP_DEBUG
+  static unsigned long last = 0;
+  if (millis() - last > 60000) {
+    last = millis();
+    DIAG(F("+"));
+  }
+#endif
+  ESP.wdtFeed();
+}
+#endif //ESP_FAMILY

WifiESP8266.h

@@ -0,0 +1,39 @@
+/*
+ *  © 2021, Harald Barth.
+ *
+ *  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/>.
+ */
+
+#if defined(ARDUINO_ARCH_ESP8266)
+#ifndef WifiESP8266_h
+#define WifiESP8266_h
+
+#include "FSH.h"
+
+class WifiESP
+{
+
+public:
+  static bool setup(const char *wifiESSID,
+		    const char *wifiPassword,
+		    const char *hostname,
+		    const int port,
+		    const byte channel);
+  static void loop();
+private:
+};
+#endif //WifiESP8266_h
+#endif //ESP8266

WifiInterface.cpp

@@ -17,9 +17,10 @@
     You should have received a copy of the GNU General Public License
     along with CommandStation.  If not, see <https://www.gnu.org/licenses/>.
 */
+#include "WifiInterface.h"        /* config.h included there */
+#ifndef ESP_FAMILY
 #ifndef ARDUINO_AVR_UNO_WIFI_REV2
 // This code is NOT compiled on a unoWifiRev2 processor which uses a different architecture 
-#include "WifiInterface.h"        /* config.h included there */
 #include <avr/pgmspace.h>
 #include "DIAG.h"
 #include "StringFormatter.h"
@@ -370,4 +371,5 @@ void WifiInterface::loop() {
   }
 }
 
-#endif
+#endif //ARDUINO_AVR_UNO_WIFI_REV2
+#endif //ESP_FAMILY

WifiInterface.h

@@ -19,6 +19,8 @@
  */
 #ifndef WifiInterface_h
 #define WifiInterface_h
+#include "defines.h"
+#ifndef ESP_FAMILY
 #include "FSH.h"
 #include "DCCEXParser.h"
 #include <Arduino.h>
@@ -50,4 +52,5 @@ private:
   static bool checkForOK(const unsigned int timeout, const FSH *waitfor, bool echo, bool escapeEcho = true);
   static bool connected;
 };
-#endif
+#endif //ESP_FAMILY
+#endif 

config.example.h

@@ -41,7 +41,29 @@ The configuration file for DCC-EX Command Station
 //   |
 //   +-----------------------v
 //
-#define MOTOR_SHIELD_TYPE STANDARD_MOTOR_SHIELD
+//#define MOTOR_SHIELD_TYPE STANDARD_MOTOR_SHIELD
+
+// https://randomnerdtutorials.com/esp8266-pinout-reference-gpios/
+// 4 high at boot
+#define ESP8266_MOTOR_SHIELD F("ESP8266"),					\
+ new MotorDriver(D3, D5, UNUSED_PIN, UNUSED_PIN, UNUSED_PIN, 2.99, 2000, UNUSED_PIN),\
+ new MotorDriver(D2, D6, UNUSED_PIN, UNUSED_PIN, A0        , 2.99, 2000, UNUSED_PIN)
+
+// ESP32 ADC1 only supported GPIO pins 32 to 39, for example
+// ADC1 CH4 = GPIO32, ADC1 CH5 = GPIO33, ADC1 CH0 = GPIO36
+//
+// Adjust pin usage according to info in
+// https://randomnerdtutorials.com/esp32-adc-analog-read-arduino-ide/
+// https://randomnerdtutorials.com/esp32-pinout-reference-gpios/
+//
+// Adjust conversion factor according to your voltage divider.
+//
+#define ESP32_MOTOR_SHIELD F("ESP32"), \
+ new MotorDriver(16, 17, UNUSED_PIN, UNUSED_PIN, 32, 2.00, 2000, UNUSED_PIN),\
+ new MotorDriver(18, 19, UNUSED_PIN, UNUSED_PIN, 33, 2.00, 2000, UNUSED_PIN)
+
+#define MOTOR_SHIELD_TYPE ESP32_MOTOR_SHIELD
+
 /////////////////////////////////////////////////////////////////////////////////////
 //
 // The IP port to talk to a WIFI or Ethernet shield.
@@ -53,6 +75,8 @@ The configuration file for DCC-EX Command Station
 // NOTE: Only supported on Arduino Mega
 // Set to false if you not even want it on the Arduino Mega
 //
+// Currently ESP32 single core only works with WIFI ON because of Watchdog code
+// and if you have an ESP32 you probably want WIFI anyway.
 #define ENABLE_WIFI true
 
 /////////////////////////////////////////////////////////////////////////////////////

defines.h

@@ -1,5 +1,5 @@
 /*
-    © 2020, Harald Barth.
+    © 2020,2021 Harald Barth.
 
     This file is part of CommandStation-EX
 
@@ -31,14 +31,34 @@
   #endif
 #endif
 
+////////////////////////////////////////////////////////////////////////////////
+//
+#if defined(ARDUINO_ARCH_ESP8266)
+#define ESP_FAMILY
+//#define ESP_DEBUG
+#define SLOW_ANALOG_READ
+#endif
+
+////////////////////////////////////////////////////////////////////////////////
+//
+#if defined(ARDUINO_ARCH_ESP32)
+#define ESP_FAMILY
+#define SLOW_ANALOG_READ
+#else
+#define portENTER_CRITICAL(A) do {} while (0)
+#define portEXIT_CRITICAL(A) do {} while (0)
+#endif
+
+
 ////////////////////////////////////////////////////////////////////////////////
 //
 // WIFI_ON: All prereqs for running with WIFI are met
 // Note: WIFI_CHANNEL may not exist in early config.h files so is added here if needed.
 
-#if (defined(ARDUINO_AVR_MEGA) || defined(ARDUINO_AVR_MEGA2560) || defined(ARDUINO_SAMD_ZERO)  || defined(TEENSYDUINO))
+#if (defined(ARDUINO_AVR_MEGA) || defined(ARDUINO_AVR_MEGA2560) || defined(ARDUINO_SAMD_ZERO)  || defined(TEENSYDUINO) || defined(ESP_FAMILY))
  #define BIG_RAM
 #endif 
+
 #if ENABLE_WIFI && defined(BIG_RAM)
 #define WIFI_ON true
 #ifndef WIFI_CHANNEL
@@ -69,4 +89,4 @@
   #define RMFT_ACTIVE
 #endif
 
-#endif
+#endif

esp32wdt.txt

@@ -0,0 +1,67 @@
+The ESP-IDF has interrupt watchdogs and task watchdogs. Normally on
+each core there is a very low prio idle task (IDLE0, ILDE1) that feeds
+the watchdog (an internal timer) and if that timer expires a
+reboot/reset happens. This thought to enure that even the lowest prio
+tasks get run ever.
+
+Now enter the Arduino IDE generated task loop(). When there are two cores,
+loop() is run on core1. If loop runs continiously, IDLE1 is never run and
+triggers the watchdog. It is said that this can be previented by one
+of the following:
+
+1. Call delay(X) with big enough X
+2. Call yield()
+
+While the delay() method works, big enough X to run idle seem to be in
+the ms range and there are definitely applications that can not accept
+a several ms long pause in loop().
+
+The yield() method does not work because it only seems not to yield to
+a low prio task like IDLE1 in all circumstances.
+
+Then the makers of the Arduino IDE did get the brilliant idea to
+disable that IDLE1 calls the watchdog. Then loop() can spin on core1
+and other tasks (like wifi or interrupts or whatever) can run on core0
+and are watched by the IDLE0 watchdog. All swell and well. Almost.
+
+Enter: SINGLE CORE ESP32
+
+As the IDLE0 watchdog is not disabled it will fire when loop() runs on
+core0. The next idea is to feed the watchdog from loop() just
+alongside the yield. There is a function called esp_task_wdt_feed(),
+so can that be used to feed the watchdog? Yes and no. While it
+will feed the watchdog, there is as well as check in the ESP-IDF
+that the watchdog is fed from ALL tasks that should feed it. So
+if the setup is that IDLE0 should feed the watchdog, we can not
+get away by calling esp_task_wdt_feed() from loop(). BUMMER!
+
+But there seems to be a way around this. The watchdog is implemented
+by low level timers/counters and these are accessible. So we can feed
+the dog behind the back of the ESP-IDF:
+
+#include "soc/timer_group_struct.h"
+#include "soc/timer_group_reg.h"
+void feedTheDog(){
+  // feed dog 0
+  TIMERG0.wdt_wprotect=TIMG_WDT_WKEY_VALUE; // write enable
+  TIMERG0.wdt_feed=1;                       // feed dog
+  TIMERG0.wdt_wprotect=0;                   // write protect
+  // feed dog 1
+  TIMERG1.wdt_wprotect=TIMG_WDT_WKEY_VALUE; // write enable
+  TIMERG1.wdt_feed=1;                       // feed dog
+  TIMERG1.wdt_wprotect=0;                   // write protect
+}
+
+As I do not have a single core ESP32 I tested this by enabling the
+IDLE1 watchdog (which normally is disabled) and checking that I
+do get watchdog resets. Then I call feedTheDog() from loop()
+and the resets disappear. So I guess the feeding operation is
+successful. For a single core ESP32 of course only dog0 has
+to be fed.
+
+Feed dog directly behind back of the ESP-IDF routines:
+https://forum.arduino.cc/t/esp32-a-better-way-than-vtaskdelay-to-get-around-watchdog-crash/596889/13
+Disable/Endable WDT code:
+https://github.com/espressif/arduino-esp32/commit/b8f8502f
+Get/set taskid on cores:
+https://techtutorialsx.com/2017/05/09/esp32-get-task-execution-core/

freeMemory.cpp

@@ -1,5 +1,5 @@
 /*
- *  © 2020, Harald Barth
+ *  © 2020,2021 Harald Barth
  *  © 2021, Neil McKechnie
  *  
  *  This file is part of Asbelos DCC-EX
@@ -27,6 +27,8 @@ extern "C" char* sbrk(int);
 #elif defined(__AVR__)
 extern char *__brkval;
 extern char *__malloc_heap_start;
+#elif defined(ARDUINO_ARCH_ESP8266) || defined(ARDUINO_ARCH_ESP32)
+// supported but nothing needed here
 #else
 #error Unsupported board type
 #endif
@@ -34,7 +36,7 @@ extern char *__malloc_heap_start;
 
 static volatile int minimum_free_memory = __INT_MAX__;
 
-#if !defined(__IMXRT1062__)
+#if !defined(__IMXRT1062__) && !defined(ARDUINO_ARCH_ESP8266) && !defined(ARDUINO_ARCH_ESP32)
 static inline int freeMemory() {
   char top;
 #if defined(__arm__)
@@ -55,7 +57,18 @@ int minimumFreeMemory() {
   return retval;
 }
 
+#elif defined(ARDUINO_ARCH_ESP8266) || defined(ARDUINO_ARCH_ESP32)
+// ESP8266 and ESP32
+static inline int freeMemory() {
+  return ESP.getFreeHeap();
+}
+// Return low memory value.
+int minimumFreeMemory() {
+  int retval = minimum_free_memory;
+  return retval;
+}
 #else
+// All types of TEENSYs
 #if defined(ARDUINO_TEENSY40)
   static const unsigned DTCM_START = 0x20000000UL;
   static const unsigned OCRAM_START = 0x20200000UL;
@@ -108,4 +121,3 @@ void updateMinimumFreeMemory(unsigned char extraBytes) {
   if (spare < 0) spare = 0;
   if (spare < minimum_free_memory) minimum_free_memory = spare;
 }
-

version.h

@@ -3,7 +3,7 @@
 
 #include "StringFormatter.h"
 
-#define VERSION "3.2.0 rc4"
+#define VERSION "3.2.0 ESP32"
 // 3.2.0 Major functional and non-functional changes.
 //       New HAL added for I/O (digital and analogue inputs and outputs, servos etc).
 //         Support for MCP23008, MCP23017 and PCF9584 I2C GPIO Extender modules.