Fix ZCD pulse and frequency detection

(cherry picked from commit 21158c936e6701581100ea5d46cb3fb2d640115d)

lib/DimmableLight/src/thyristor.cpp

@@ -272,7 +272,6 @@ void ARDUINO_ISR_ATTR zero_cross_pulse_int() {
     // I decided to use "16" because is a power of 2, very fast to be computed.
     if (semiPeriodLength && diff > semiPeriodLength * 16) {
       queue.reset();
-      pulses.reset();
     } else {
       // If filtering has passed, I can update the moving average
       queue.add(diff);
@@ -469,75 +468,24 @@ void Thyristor::setFrequency(float frequency) {
 }
 
 uint16_t Thyristor::getPulseWidth() {
-  noInterrupts();
-  uint32_t diff = micros() - lastTime;
-  if (semiPeriodLength && diff > semiPeriodLength) {
-    pulses.reset();
-  }
-  uint16_t avg = pulses.avg();
-  interrupts();
-  return avg;
+  return pulses.avg();
 }
 
 uint16_t Thyristor::getMaxPulseWidth() {
-  noInterrupts();
-  uint32_t diff = micros() - lastTime;
-  if (semiPeriodLength && diff > semiPeriodLength) {
-    pulses.reset();
-  }
-  uint16_t max = pulses.max();
-  interrupts();
-  return max;
+  return pulses.max();
 }
 
 uint16_t Thyristor::getMinPulseWidth() {
-  noInterrupts();
-  uint32_t diff = micros() - lastTime;
-  if (semiPeriodLength && diff > semiPeriodLength) {
-    pulses.reset();
-  }
-  uint16_t min = pulses.min();
-  interrupts();
-  return min;
+  return pulses.min();
 }
 
 uint16_t Thyristor::getLastPulseWidth() {
-  noInterrupts();
-  uint32_t diff = micros() - lastTime;
-  if (semiPeriodLength && diff > semiPeriodLength) {
-    pulses.reset();
-  }
-  uint16_t last = pulses.last();
-  interrupts();
-  return last;
+  return pulses.last();
 }
 
-float Thyristor::getDetectedFrequency() {
-  float c;
-  float tot;
-  {
-    // Stop interrupt to freeze variables modified or accessed in the interrupt
-    noInterrupts();
-
-    // "diff" is correct even when rolling back, because all of them are unsigned
-    uint32_t diff = micros() - lastTime;
-
-    // if diff is very very greater than the theoretical value, the electrical signal
-    // can be considered as lost for a while.
-    // I decided to use "16" because is a power of 2, very fast to be computed.
-    if (semiPeriodLength && diff > semiPeriodLength * 16) {
-      queue.reset();
-    }
-
-    c = queue.count();
-    tot = queue.sum();
-    interrupts();
-  }
-
-  // We need at least a sample to return a value different from 0
-  // *1000000: us
-  // /2: from semiperiod to full period
-  return tot > 0 ? (c * 500000 / tot) : 0;
+float Thyristor::getPulseFrequency() {
+  uint32_t pulsePeriod = queue.avg();
+  return pulsePeriod == 0 ? 0 : 1000000 / (float)pulsePeriod;
 }
 
 Thyristor::Thyristor(int pin) : pin(pin), delay(semiPeriodLength) {

lib/DimmableLight/src/thyristor.h

@@ -130,7 +130,7 @@ class Thyristor {
      *
      * NOTE: when (re)starting, it will take a while before returning a value different from 0.
      */
-    static float getDetectedFrequency();
+    static float getPulseFrequency();
 
     static const uint8_t N = 2;
 

lib/MycilaDimmer/MycilaDimmer.h

@@ -71,8 +71,8 @@ namespace Mycila {
       // At 0% power, the phase angle is equal to PI
       // At 100% power, the phase angle is equal to 0
       float getPhaseAngle() const {
-        // angle_rad = PI * delay_s / period_s
-        return PI * _zcd->getPulseFrequency() * getFiringDelay() / 1000000;
+        // angle_rad = PI * delay_us / period_us
+        return PI * getFiringDelay() / _zcd->getSemiPeriod();
       }
 
     private:

lib/MycilaDimmer/MycilaZCD.cpp

@@ -51,15 +51,12 @@ void Mycila::ZCD::begin(const int8_t pin, const uint8_t frequency) {
   Thyristor::setSyncPin(_pin);
   Thyristor::begin();
 
-  _frequencyUpdater.attach(1, +[](ZCD* instance) { instance->_measuredGridFrequency = Thyristor::getDetectedFrequency(); }, this);
-
   _enabled = true;
 }
 
 void Mycila::ZCD::end() {
   if (_enabled) {
     LOGI(TAG, "Disable Zero-Cross Detection...");
-    _frequencyUpdater.detach();
     _enabled = false;
     Thyristor::setFrequency(0);
     Thyristor::end();
@@ -68,6 +65,8 @@ void Mycila::ZCD::end() {
 }
 
 uint16_t Mycila::ZCD::getSemiPeriod() const { return _enabled ? Thyristor::getSemiPeriod() : 0; }
+
+float Mycila::ZCD::getPulseFrequency() const { return _enabled ? Thyristor::getPulseFrequency() : 0; }
 uint16_t Mycila::ZCD::getAvgPulseWidth() const { return _enabled ? Thyristor::getPulseWidth() : 0; }
 uint16_t Mycila::ZCD::getMaxPulseWidth() const { return _enabled ? Thyristor::getMaxPulseWidth() : 0; }
 uint16_t Mycila::ZCD::getLastPulseWidth() const { return _enabled ? Thyristor::getLastPulseWidth() : 0; }

lib/MycilaDimmer/MycilaZCD.h

@@ -5,7 +5,6 @@
 #pragma once
 
 #include <ArduinoJson.h>
-#include <Ticker.h>
 
 #include <esp32-hal-gpio.h>
 
@@ -23,11 +22,8 @@ namespace Mycila {
       // 60Hz => 8333
       uint16_t getSemiPeriod() const;
 
-      // Grid frequency in Hz based on the Zero-Cross pulse frequency
-      float getCurrentFrequency() const { return _enabled ? _measuredGridFrequency : 0; }
-
       // Zero-Cross pulse information
-      float getPulseFrequency() const { return _enabled ? _measuredGridFrequency * 2 : 0; }
+      float getPulseFrequency() const;
       uint16_t getAvgPulseWidth() const;
       uint16_t getLastPulseWidth() const;
       uint16_t getMaxPulseWidth() const;
@@ -45,8 +41,6 @@ namespace Mycila {
 
     private:
       bool _enabled = false;
-      volatile float _measuredGridFrequency = 0;
-      Ticker _frequencyUpdater;
       gpio_num_t _pin = GPIO_NUM_NC;
   };
 } // namespace Mycila