NucleoTimerSync for DC mode tracks

DCCTimerSTM32.cpp

@@ -1,6 +1,7 @@
 /*
  *  © 2023 Neil McKechnie
  *  © 2022-2024 Paul M. Antoine
+ *  © 2025 Herb Morton
  *  © 2021 Mike S
  *  © 2021, 2023 Harald Barth
  *  © 2021 Fred Decker
@@ -36,6 +37,21 @@
 #include "DIAG.h"
 #include <wiring_private.h>
 
+// DC mode timers enable the PWM signal on select pins.
+// Code added to sync timers which have the same frequency.
+// Function prototypes
+void refreshDCmodeTimers();
+void resetCounterDCmodeTimers();
+
+HardwareTimer *Timer1 = new HardwareTimer(TIM1);
+HardwareTimer *Timer2 = new HardwareTimer(TIM2);
+HardwareTimer *Timer3 = new HardwareTimer(TIM3);
+HardwareTimer *Timer4 = new HardwareTimer(TIM4);
+HardwareTimer *Timer9 = new HardwareTimer(TIM9);
+#if defined(TIM13)
+HardwareTimer *Timer13 = new HardwareTimer(TIM13);
+#endif
+
 #if defined(ARDUINO_NUCLEO_F401RE)
 // Nucleo-64 boards don't have additional serial ports defined by default
 // Serial1 is available on the F401RE, but not hugely convenient.
@@ -290,7 +306,7 @@ void DCCTimer::DCCEXanalogWriteFrequency(uint8_t pin, uint32_t f) {
   else if (f >= 3)
     DCCTimer::DCCEXanalogWriteFrequencyInternal(pin, 16000);
   else if (f >= 2)
-    DCCTimer::DCCEXanalogWriteFrequencyInternal(pin, 3400);
+    DCCTimer::DCCEXanalogWriteFrequencyInternal(pin, 3600);
   else if (f == 1)
     DCCTimer::DCCEXanalogWriteFrequencyInternal(pin, 480);
   else
@@ -328,7 +344,8 @@ void DCCTimer::DCCEXanalogWriteFrequencyInternal(uint8_t pin, uint32_t frequency
     if (pin_timer[pin] != NULL)
     {
       pin_timer[pin]->setPWM(pin_channel[pin], pin, frequency, 0); // set frequency in Hertz, 0% dutycycle
-      DIAG(F("DCCEXanalogWriteFrequency::Pin %d on Timer Channel %d, frequency %d"), pin, pin_channel[pin], frequency);
+      DIAG(F("DCCEXanalogWriteFrequency::Pin %d on Timer %d Channel %d, frequency %d"), pin, pin_timer[pin], pin_channel[pin], frequency);
+      resetCounterDCmodeTimers();
     }
     else
       DIAG(F("DCCEXanalogWriteFrequency::failed to allocate HardwareTimer instance!"));
@@ -341,6 +358,7 @@ void DCCTimer::DCCEXanalogWriteFrequencyInternal(uint8_t pin, uint32_t frequency
       pinmap_pinout(digitalPinToPinName(pin), PinMap_TIM); // ensure the pin has been configured!
       pin_timer[pin]->setOverflow(frequency, HERTZ_FORMAT); // Just change the frequency if it's already running!
       DIAG(F("DCCEXanalogWriteFrequency::setting frequency to %d"), frequency);
+      resetCounterDCmodeTimers();
     }
   }
   channel_frequency[pin] = frequency;
@@ -365,6 +383,8 @@ void DCCTimer::DCCEXanalogWrite(uint8_t pin, int value, bool invert) {
         pin_timer[pin]->setCaptureCompare(pin_channel[pin], duty_cycle, PERCENT_COMPARE_FORMAT); // DCC_EX_PWM_FREQ Hertz, duty_cycle% dutycycle
         DIAG(F("DCCEXanalogWrite::Pin %d, value %d, duty cycle %d"), pin, value, duty_cycle);
       // }
+      refreshDCmodeTimers();
+      resetCounterDCmodeTimers();
     }
     else
       DIAG(F("DCCEXanalogWrite::Pin %d is not configured for PWM!"), pin);
@@ -659,4 +679,35 @@ void ADCee::begin() {
 #endif
   interrupts();
 }
+
+// NOTE:  additional testing is needed to check the DCC signal 
+//        where the DCC signal pin is a pwm pin on timers 1, 2, 3, 4, 9, 13
+//        or the brake pin is defined on a different timer.
+//        -- example:  F411RE/F446RE - pin 10 on stacked EX8874  
+// lines added to sync timers -- 
+//    not exact sync, but timers with the same frequency should be in sync
+void refreshDCmodeTimers() {
+  Timer1->refresh();
+  Timer2->refresh();
+  Timer3->refresh();
+  Timer4->refresh();
+  Timer9->refresh();
+  #if defined(TIM13)
+  Timer13->refresh();
+  #endif
+}
+
+// Function to synchronize timers - called every time there is powerON commmand for any DC track
+void resetCounterDCmodeTimers() {
+    // Reset the counter for all DC mode timers
+    TIM1->CNT = 0;
+    TIM2->CNT = 0;
+    TIM3->CNT = 0;
+    TIM4->CNT = 0;
+    TIM9->CNT = 0;
+    #if defined(TIM13)
+    TIM13->CNT = 0;
+    #endif
+}
+
 #endif

MotorDriver.cpp

@@ -1,6 +1,6 @@
 /*
  *  © 2022-2024 Paul M Antoine
- *  © 2024 Herb Morton
+ *  © 2024-2025 Herb Morton
  *  © 2021 Mike S
  *  © 2021 Fred Decker
  *  © 2020-2023 Harald Barth
@@ -371,8 +371,8 @@ void MotorDriver::setDCSignal(byte speedcode, uint8_t frequency /*default =0*/)
     }
 #endif
     //DIAG(F("Brake pin %d value %d freqency %d"), brakePin, brake, f);
-    DCCTimer::DCCEXanalogWrite(brakePin, brake, invertBrake);
     DCCTimer::DCCEXanalogWriteFrequency(brakePin, f); // set DC PWM frequency
+    DCCTimer::DCCEXanalogWrite(brakePin, brake, invertBrake);  // line swapped to set frequency first
 #else // all AVR here
     DCCTimer::DCCEXanalogWriteFrequency(brakePin, frequency); // frequency steps
     analogWrite(brakePin, invertBrake ? 255-brake : brake);

TrackManager.cpp

@@ -2,7 +2,7 @@
  *  © 2022-2025 Chris Harlow
  *  © 2022-2024 Harald Barth
  *  © 2023-2024 Paul M. Antoine
- *  © 2024 Herb Morton
+ *  © 2024-2025 Herb Morton
  *  © 2023 Colin Murdoch
  *  All rights reserved.
  *  
@@ -557,6 +557,20 @@ void TrackManager::setTrackPower(TRACK_MODE trackmodeToMatch, POWERMODE powermod
   }
   if (didChange)
     CommandDistributor::broadcastPower();
+
+  // re-initialize DC mode timer settings following powerON  
+  if (powermode == POWERMODE::ON) {  
+    #ifdef ARDUINO_ARCH_STM32
+//        for (byte i=0;i<=lastTrack;i++)  {
+//          setTrackPowerF439ZI(i);
+//        }
+          // repeated in case the <F29..31 was set on a later track than power
+          // Note:  this retains power but prevents speed doubling
+        for (byte i=0;i<lastTrack;i++)  {
+           setTrackPowerF439ZI(i);
+        }
+      #endif
+  }
 }
 
 // Set track power for this track, inependent of mode
@@ -587,6 +601,20 @@ void TrackManager::setTrackPower(POWERMODE powermode, byte t) {
   driver->setPower(powermode);
   if (oldpower != driver->getPower())
     CommandDistributor::broadcastPower();
+
+  // re-initialize DC mode timer settings following powerON  
+  if (powermode == POWERMODE::ON) {  
+    #ifdef ARDUINO_ARCH_STM32
+        for (byte i=0;i<=lastTrack;i++)  {
+          setTrackPowerF439ZI(i);
+        }
+          // repeated in case the <F29..31 was set on a later track than power
+          // Note:  this retains power but prevents speed doubling
+        for (byte i=0;i<lastTrack;i++)  {
+           setTrackPowerF439ZI(i);
+        }
+      #endif
+  }
 }
 
 // returns state of the one and only prog track
@@ -709,3 +737,38 @@ TRACK_MODE TrackManager::getMode(byte t) {
 int16_t TrackManager::returnDCAddr(byte t) {
     return (trackDCAddr[t]);
 }
+
+// Set track power for EACH track, independent of mode 
+// This updates the settings so that speed is correct
+// following a frequency change - DC mode
+void TrackManager::setTrackPowerF439ZI(byte t) {
+  MotorDriver *driver=track[t];
+  if (driver == NULL) { // track is not defined at all
+   // DIAG(F("Error: Track %c does not exist"), t+'A');
+    return;
+  }
+  TRACK_MODE trackmode = driver->getMode();
+  POWERMODE powermode = driver->getPower();   // line added to enable processing for DC mode tracks
+  POWERMODE oldpower = driver->getPower();
+  //if (trackmode & TRACK_MODE_NONE) {
+  //  driver->setBrake(true);     // Track is unused. Brake is good to have.
+  //  powermode = POWERMODE::OFF; // Track is unused. Force it to OFF
+  //} else 
+  if (trackmode & TRACK_MODE_DC) { // includes inverted DC (called DCX)
+    if (powermode == POWERMODE::ON) {
+      driver->setBrake(true);   // DC starts with brake on
+      applyDCSpeed(t);          // speed match DCC throttles
+    }
+  } 
+  //else /* MAIN PROG EXT BOOST */ {
+  //  if (powermode == POWERMODE::ON) {
+  //    // toggle brake before turning power on - resets overcurrent error
+  //    // on the Pololu board if brake is wired to ^D2.
+  //    driver->setBrake(true);
+  //    driver->setBrake(false); // DCC runs with brake off
+  //  }
+  //}
+  driver->setPower(powermode);
+  if (oldpower != driver->getPower())
+    CommandDistributor::broadcastPower();
+}

TrackManager.h

@@ -1,6 +1,7 @@
 /*
  *  © 2022 Chris Harlow
  *  © 2022-2024 Harald Barth
+ *  © 2025 Herb Morton
  *  © 2023 Colin Murdoch
  * 
  *  All rights reserved.
@@ -69,6 +70,7 @@ class TrackManager {
     static void setTrackPower(TRACK_MODE trackmode, POWERMODE powermode);
     static void setMainPower(POWERMODE mode) {setTrackPower(TRACK_MODE_MAIN, mode);}
     static void setProgPower(POWERMODE mode) {setTrackPower(TRACK_MODE_PROG, mode);}
+    static void setTrackPowerF439ZI(byte t);
 
     static const int16_t MAX_TRACKS=8;
     static bool setTrackMode(byte track, TRACK_MODE mode, int16_t DCaddr=0);

version.h

@@ -4,6 +4,7 @@
 #include "StringFormatter.h"
 
 #define VERSION "5.5.23"
+// 5.5.24 - Sync DC mode tracks - Nucleo-F4
 // 5.5.23 - Reminder loop Idle packet optimization
 // 5.5.22 - (5.4.9) Handle non-compliant decoders returning 255 for cv 20 and confusing <R> with bad consist addresses.
 //        - DCC 5mS gap to same loco DCC packet restriction