variable frequency step #1

DCCTimer.h

@@ -85,6 +85,7 @@ class DCCTimer {
   static void reset();
   
 private:
+  static void DCCEXanalogWriteFrequencyInternal(uint8_t pin, uint32_t frequency);
   static int freeMemory();
   static volatile int minimum_free_memory;
   static const int DCC_SIGNAL_TIME=58;  // this is the 58uS DCC 1-bit waveform half-cycle 

DCCTimerAVR.cpp

@@ -29,6 +29,7 @@
 #include <avr/boot.h> 
 #include <avr/wdt.h>
 #include "DCCTimer.h"
+#include "DIAG.h"
 #ifdef DEBUG_ADC
 #include "TrackManager.h"
 #endif
@@ -125,6 +126,76 @@ void DCCTimer::reset() {
 
 }
 
+void DCCTimer::DCCEXanalogWriteFrequency(uint8_t pin, uint32_t f) {
+  DCCTimer::DCCEXanalogWriteFrequencyInternal(pin, f);
+}
+void DCCTimer::DCCEXanalogWriteFrequencyInternal(uint8_t pin, uint32_t fbits) {
+#if defined(ARDUINO_AVR_UNO)
+      // Not worth doin something here as:
+      // If we are on pin 9 or 10 we are on Timer1 and we can not touch Timer1 as that is our DCC source.
+      // If we are on pin 5 or 6 we are on Timer 0 ad we can not touch Timer0 as that is millis() etc.
+      // We are most likely not on pin 3 or 11 as no known motor shield has that as brake.
+#endif
+#if defined(ARDUINO_AVR_MEGA) || defined(ARDUINO_AVR_MEGA2560)
+  uint8_t abits;
+  uint8_t bbits;
+  if (pin == 9 || pin == 10) { // timer 2 is different
+
+    if (fbits >= 3)
+      abits = B11;
+    else
+      abits = B01;
+
+    if (fbits >= 3)
+      bbits = B0001;
+    else if (fbits == 2)
+      bbits = B0010;
+    else if (fbits == 1)
+      bbits = B0100;
+    else
+      bbits = B0110;
+
+    TCCR2A = (TCCR2A & B11111100) | abits; // set WGM0 and WGM1
+    TCCR2B = (TCCR2B & B11110000) | bbits; // set WGM2 and 3 bits of prescaler
+    DIAG(F("Timer 2 A=%x B=%x"), TCCR2A, TCCR2B);
+
+  } else { // not timer 9 or 10
+    abits = B01;
+
+    if (fbits >= 3)
+      bbits = B1001;
+    else if (fbits == 2)
+      bbits = B0010;
+    else if (fbits == 1)
+      bbits = B0011;
+    else
+      bbits = B0100;
+
+    switch (pin) {
+      // case 9 and 10 taken care of above by if()
+    case 6:
+    case 7:
+    case 8:
+      // Timer4
+      TCCR4A = (TCCR4A & B11111100) | abits; // set WGM0 and WGM1
+      TCCR4B = (TCCR4B & B11100000) | bbits; // set WGM2 and WGM3 and divisor
+      DIAG(F("Timer 4 A=%x B=%x"), TCCR4A, TCCR4B);
+      break;
+    case 46:
+    case 45:
+    case 44:
+      // Timer5
+      TCCR5A = (TCCR5A & B11111100) | abits; // set WGM0 and WGM1
+      TCCR5B = (TCCR5B & B11100000) | bbits; // set WGM2 and WGM3 and divisor
+      DIAG(F("Timer 5 A=%x B=%x"), TCCR5A, TCCR5B);
+      break;
+    default:
+      break;
+    }
+  }
+#endif
+}
+
 #if defined(ARDUINO_AVR_MEGA) || defined(ARDUINO_AVR_MEGA2560)
 #define NUM_ADC_INPUTS 16
 #else

DCCTimerESP.cpp

@@ -151,10 +151,22 @@ void DCCTimer::reset() {
    ESP.restart();
 }
 
+void DCCTimer::DCCEXanalogWriteFrequency(uint8_t pin, uint32_t f) {
+  if (f >= 16)
+    DCCTimer::DCCEXanalogWriteFrequencyInternal(pin, f);
+  else if (f >= 3)
+    DCCTimer::DCCEXanalogWriteFrequencyInternal(pin, 62500);
+  else if (f == 2)
+    DCCTimer::DCCEXanalogWriteFrequencyInternal(pin, 3400);
+  else if (f == 1)
+    DCCTimer::DCCEXanalogWriteFrequencyInternal(pin, 480);
+  else
+    DCCTimer::DCCEXanalogWriteFrequencyInternal(pin, 131);
+}
+
 #include "esp32-hal.h"
 #include "soc/soc_caps.h"
 
-
 #ifdef SOC_LEDC_SUPPORT_HS_MODE
 #define LEDC_CHANNELS           (SOC_LEDC_CHANNEL_NUM<<1)
 #else
@@ -164,7 +176,7 @@ void DCCTimer::reset() {
 static int8_t pin_to_channel[SOC_GPIO_PIN_COUNT] = { 0 };
 static int cnt_channel = LEDC_CHANNELS;
 
-void DCCTimer::DCCEXanalogWriteFrequency(uint8_t pin, uint32_t frequency) {
+void DCCTimer::DCCEXanalogWriteFrequencyInternal(uint8_t pin, uint32_t frequency) {
   if (pin < SOC_GPIO_PIN_COUNT) {
     if (pin_to_channel[pin] != 0) {
       ledcSetup(pin_to_channel[pin], frequency, 8);

DCCTimerSTM32.cpp

@@ -257,6 +257,19 @@ void DCCTimer::reset() {
     while(true) {};
 }
 
+void DCCTimer::DCCEXanalogWriteFrequency(uint8_t pin, uint32_t f) {
+  if (f >= 16)
+    DCCTimer::DCCEXanalogWriteFrequencyInternal(pin, f);
+  else if (f >= 3)
+    DCCTimer::DCCEXanalogWriteFrequencyInternal(pin, 62500);
+  else if (f == 2)
+    DCCTimer::DCCEXanalogWriteFrequencyInternal(pin, 3400);
+  else if (f == 1)
+    DCCTimer::DCCEXanalogWriteFrequencyInternal(pin, 480);
+  else
+    DCCTimer::DCCEXanalogWriteFrequencyInternal(pin, 131);
+}
+
 // TODO: rationalise the size of these... could really use sparse arrays etc.
 static HardwareTimer * pin_timer[100] = {0};
 static uint32_t channel_frequency[100] = {0};
@@ -267,7 +280,7 @@ static uint32_t pin_channel[100] = {0};
 // sophisticated about detecting any clash between the timer we'd like to use for PWM and the ones
 // currently used for HA so they don't interfere with one another. For now we'll just make PWM
 // work well... then work backwards to integrate with HA mode if we can.
-void DCCTimer::DCCEXanalogWriteFrequency(uint8_t pin, uint32_t frequency)
+void DCCTimer::DCCEXanalogWriteFrequencyInternal(uint8_t pin, uint32_t frequency)
 {
   if (pin_timer[pin] == NULL) {
     // Automatically retrieve TIM instance and channel associated to pin

MotorDriver.cpp

@@ -328,45 +328,19 @@ uint16_t taurustones[28] = { 165, 175, 196, 220,
 void MotorDriver::setDCSignal(byte speedcode) {
   if (brakePin == UNUSED_PIN)
     return;
-  switch(brakePin) {
-#if defined(ARDUINO_AVR_UNO)
-    // Not worth doin something here as:
-    // If we are on pin 9 or 10 we are on Timer1 and we can not touch Timer1 as that is our DCC source.
-    // If we are on pin 5 or 6 we are on Timer 0 ad we can not touch Timer0 as that is millis() etc.
-    // We are most likely not on pin 3 or 11 as no known motor shield has that as brake.
-#endif
-#if defined(ARDUINO_AVR_MEGA) || defined(ARDUINO_AVR_MEGA2560)
-  case 9:
-  case 10:
-    // Timer2 (is differnet)
-    TCCR2A = (TCCR2A & B11111100) | B00000001; // set WGM1=0 and WGM0=1 phase correct PWM
-    TCCR2B = (TCCR2B & B11110000) | B00000110; // set WGM2=0 ; set divisor on timer 2 to 1/256 for 122.55Hz
-    //DIAG(F("2 A=%x B=%x"), TCCR2A, TCCR2B);
-    break;
-  case 6:
-  case 7:
-  case 8:
-    // Timer4
-    TCCR4A = (TCCR4A & B11111100) | B00000001; // set WGM0=1 and WGM1=0 for normal PWM 8-bit
-    TCCR4B = (TCCR4B & B11100000) | B00000100; // set WGM2=0 and WGM3=0 for normal PWM 8 bit and div 1/256 for 122.55Hz
-    break;
-  case 46:
-  case 45:
-  case 44:
-    // Timer5
-    TCCR5A = (TCCR5A & B11111100) | B00000001; // set WGM0=1 and WGM1=0 for normal PWM 8-bit
-    TCCR5B = (TCCR5B & B11100000) | B00000100; // set WGM2=0 and WGM3=0 for normal PWM 8 bit and div 1/256 for 122.55Hz
-    break;
-#endif
-  default:
-    break;
-  }
   // spedcoode is a dcc speed & direction
   byte tSpeed=speedcode & 0x7F; // DCC Speed with 0,1 stop and speed steps 2 to 127
   byte tDir=speedcode & 0x80;
   byte brake;
+
+  if (tSpeed <= 1) brake = 255;
+  else if (tSpeed >= 127) brake = 0;
+  else  brake = 2 * (128-tSpeed);
+  if (invertBrake)
+    brake=255-brake;
+
+  { // new block because of variable f
 #if defined(ARDUINO_ARCH_ESP32) || defined(ARDUINO_ARCH_STM32)
-  {
     int f = 131;
 #ifdef VARIABLE_TONES
     if (tSpeed > 2) {
@@ -376,18 +350,13 @@ void MotorDriver::setDCSignal(byte speedcode) {
     }
 #endif
     DCCTimer::DCCEXanalogWriteFrequency(brakePin, f); // set DC PWM frequency to 100Hz XXX May move to setup
-  }
-#endif
-  if (tSpeed <= 1) brake = 255;
-  else if (tSpeed >= 127) brake = 0;
-  else  brake = 2 * (128-tSpeed);
-  if (invertBrake)
-    brake=255-brake;
-#if defined(ARDUINO_ARCH_ESP32) || defined(ARDUINO_ARCH_STM32)
     DCCTimer::DCCEXanalogWrite(brakePin,brake);
-#else
+#else // all AVR here
+    DCCTimer::DCCEXanalogWriteFrequency(brakePin, 0); // 0 is lowest possible f, like 120Hz
     analogWrite(brakePin,brake);
 #endif
+  }
+
   //DIAG(F("DCSignal %d"), speedcode);
   if (HAVE_PORTA(fastSignalPin.shadowinout == &PORTA)) {
     noInterrupts();
@@ -455,39 +424,7 @@ void MotorDriver::throttleInrush(bool on) {
   }
 #else
   if(on){
-    switch(brakePin) {
+    DCCTimer::DCCEXanalogWriteFrequency(brakePin, 3);
-#if defined(ARDUINO_AVR_UNO)
-      // Not worth doin something here as:
-      // If we are on pin 9 or 10 we are on Timer1 and we can not touch Timer1 as that is our DCC source.
-      // If we are on pin 5 or 6 we are on Timer 0 ad we can not touch Timer0 as that is millis() etc.
-      // We are most likely not on pin 3 or 11 as no known motor shield has that as brake.
-#endif
-#if defined(ARDUINO_AVR_MEGA) || defined(ARDUINO_AVR_MEGA2560)
-    case 9:
-    case 10:
-      // Timer2 (is different)
-      TCCR2A = (TCCR2A & B11111100) | B00000011; // set WGM0=1 and WGM1=1 for fast PWM
-      TCCR2B = (TCCR2B & B11110000) | B00000001; // set WGM2=0 and prescaler div=1 (max)
-      DIAG(F("2 A=%x B=%x"), TCCR2A, TCCR2B);
-      break;
-    case 6:
-    case 7:
-    case 8:
-      // Timer4
-      TCCR4A = (TCCR4A & B11111100) | B00000001; // set WGM0=1 and WGM1=0 for fast PWM 8-bit
-      TCCR4B = (TCCR4B & B11100000) | B00001001; // set WGM2=1 and WGM3=0 for fast PWM 8 bit and div=1 (max)
-      break;
-    case 46:
-    case 45:
-    case 44:
-      // Timer5
-      TCCR5A = (TCCR5A & B11111100) | B00000001; // set WGM0=1 and WGM1=0 for fast PWM 8-bit
-      TCCR5B = (TCCR5B & B11100000) | B00001001; // set WGM2=1 and WGM3=0 for fast PWM 8 bit and div=1 (max)
-      break;
-#endif
-    default:
-      break;
-    }
   }
   analogWrite(brakePin,duty);
 #endif