wip:

This reverts commit 6d69f5a42e.

include/zh_avr_ac_dimmer.h

@@ -7,7 +7,7 @@
 #include "avr/interrupt.h"
 #include "util/delay.h"
 
-#define ZH_TRIAC_TIME 2 // Triac turn-on time (in microseconds). Depends on the type of triac. Tested on BTA16-600.
+#define ZH_TRIAC_TIME 1 // Triac turn-on time (in microseconds). Depends on the type of triac. Tested on BTA16-600.
 
 #define ZH_AVR_AC_DIMMER_INIT_CONFIG_DEFAULT() \
     {                                          \
@@ -18,10 +18,39 @@
         .triac_port = 0}
 
 #ifdef __cplusplus
+
 extern "C"
 {
 #endif
 
+#define ZH_ZERO_CROSSING_ON                           \
+    if (_is_zero_crossing == false)                   \
+    {                                                 \
+        switch (_init_config.triac_port)              \
+        {                                             \
+        case AVR_PORTB:                               \
+            PORTB &= ~(1 << _init_config.triac_gpio); \
+            break;                                    \
+        case AVR_PORTC:                               \
+            PORTC &= ~(1 << _init_config.triac_gpio); \
+        case AVR_PORTD:                               \
+            PORTD &= ~(1 << _init_config.triac_gpio); \
+            break;                                    \
+        default:                                      \
+            break;                                    \
+        }                                             \
+        _is_zero_crossing = true;                     \
+        break;                                        \
+    }
+
+#define ZH_ZERO_CROSSING_OFF       \
+    if (_is_zero_crossing == true) \
+    {                              \
+        _is_zero_crossing = false; \
+        flag = true;               \
+    }                              \
+    break;
+
     typedef enum
     {
         ZH_50HZ = 1,

zh_avr_ac_dimmer.c

@@ -5,6 +5,7 @@ volatile static bool _is_dimmer_work = false;
 volatile static uint8_t _dimmer_value = 0;
 volatile static uint8_t _dimmer_count = 0;
 static bool _is_initialized = false;
+volatile static bool _is_zero_crossing = false;
 
 static avr_err_t _zh_avr_ac_dimmer_validate_config(const zh_avr_ac_dimmer_init_config_t *config);
 static void _zh_avr_ac_dimmer_gpio_init(void);
@@ -48,25 +49,37 @@ avr_err_t zh_avr_ac_dimmer_set(uint8_t value)
 
 void zh_avr_ac_dimmer_isr_handler(void)
 {
-    uint8_t flag = false;
+    bool flag = false;
     switch (_init_config.zero_cross_port)
     {
     case AVR_PORTB:
+        if ((PINB & (1 << _init_config.zero_cross_gpio)) == (1 << _init_config.zero_cross_gpio))
+        {
+            ZH_ZERO_CROSSING_ON;
+        }
         if ((PINB & (1 << _init_config.zero_cross_gpio)) == 0)
         {
-            flag = true;
+            ZH_ZERO_CROSSING_OFF;
         }
         break;
     case AVR_PORTC:
+        if ((PINC & (1 << _init_config.zero_cross_gpio)) == (1 << _init_config.zero_cross_gpio))
+        {
+            ZH_ZERO_CROSSING_ON;
+        }
         if ((PINC & (1 << _init_config.zero_cross_gpio)) == 0)
         {
-            flag = true;
+            ZH_ZERO_CROSSING_OFF;
         }
         break;
     case AVR_PORTD:
+        if ((PIND & (1 << _init_config.zero_cross_gpio)) == (1 << _init_config.zero_cross_gpio))
+        {
+            ZH_ZERO_CROSSING_ON;
+        }
         if ((PIND & (1 << _init_config.zero_cross_gpio)) == 0)
         {
-            flag = true;
+            ZH_ZERO_CROSSING_OFF;
         }
         break;
     default:
@@ -76,24 +89,19 @@ void zh_avr_ac_dimmer_isr_handler(void)
     {
         if (_dimmer_value != 0)
         {
-            if (_dimmer_value >= 100)
+            if (_dimmer_value == 100)
             {
                 TIMSK0 &= ~(1 << OCIE0A);
                 switch (_init_config.triac_port)
                 {
                 case AVR_PORTB:
                     PORTB |= (1 << _init_config.triac_gpio);
-                    _delay_us(ZH_TRIAC_TIME);
-                    PORTB &= ~(1 << _init_config.triac_gpio);
                     break;
                 case AVR_PORTC:
                     PORTC |= (1 << _init_config.triac_gpio);
-                    _delay_us(ZH_TRIAC_TIME);
+                    break;
-                    PORTC &= ~(1 << _init_config.triac_gpio);
                 case AVR_PORTD:
                     PORTD |= (1 << _init_config.triac_gpio);
-                    _delay_us(ZH_TRIAC_TIME);
-                    PORTD &= ~(1 << _init_config.triac_gpio);
                     break;
                 default:
                     break;
@@ -166,22 +174,23 @@ static void _zh_avr_ac_dimmer_gpio_init(void)
 
 static avr_err_t _zh_avr_ac_dimmer_timer_init(void)
 {
+    // Frequency calculator http://rcl-radio.ru/?p=111487.
     TCCR0A |= (1 << WGM01);
     switch (F_CPU)
     {
-    case 8000000:
+    case 8000000: // When operating from an internal RC generator, frequency deviation of up to 5% is possible.
         switch (_init_config.ac_dimmer_frequency)
         {
         case ZH_50HZ:
-            OCR0A = 99;
+            OCR0A = 94; // Timer tick every 0,00009524 sec.
             TCCR0B |= (1 << CS01);
             break;
-        case ZH_60HZ:
+        case ZH_60HZ: // Timer tick every 0,00007937 sec.
-            OCR0A = 82;
+            OCR0A = 78;
             TCCR0B |= (1 << CS01);
             break;
-        case ZH_400HZ:
+        case ZH_400HZ: // Timer tick every 0,0000119 sec.
-            OCR0A = 99;
+            OCR0A = 94;
             TCCR0B |= (1 << CS00);
             break;
         default:
@@ -191,15 +200,15 @@ static avr_err_t _zh_avr_ac_dimmer_timer_init(void)
     case 16000000:
         switch (_init_config.ac_dimmer_frequency)
         {
-        case ZH_50HZ:
+        case ZH_50HZ: // Timer tick every 0,0001 sec.
             OCR0A = 24;
             TCCR0B |= (1 << CS01) | (1 << CS00);
             break;
-        case ZH_60HZ:
+        case ZH_60HZ: // Timer tick every 0,00008333 sec.
             OCR0A = 165;
             TCCR0B |= (1 << CS01);
             break;
-        case ZH_400HZ:
+        case ZH_400HZ: // Timer tick every 0,0000125 sec.
             OCR0A = 24;
             TCCR0B |= (1 << CS01);
             break;
@@ -210,15 +219,15 @@ static avr_err_t _zh_avr_ac_dimmer_timer_init(void)
     case 20000000:
         switch (_init_config.ac_dimmer_frequency)
         {
-        case ZH_50HZ:
+        case ZH_50HZ: // Timer tick every 0,0001 sec.
             OCR0A = 249;
             TCCR0B |= (1 << CS01);
             break;
-        case ZH_60HZ:
+        case ZH_60HZ: // Timer tick every 0,00008333 sec.
             OCR0A = 207;
             TCCR0B |= (1 << CS01);
             break;
-        case ZH_400HZ:
+        case ZH_400HZ: // Timer tick every 0,0000125 sec.
             OCR0A = 249;
             TCCR0B |= (1 << CS00);
             break;
@@ -235,7 +244,8 @@ static avr_err_t _zh_avr_ac_dimmer_timer_init(void)
 
 ISR(TIMER0_COMPA_vect)
 {
-    if (_dimmer_count >= (100 - _dimmer_value))
+    ++_dimmer_count;
+    if (_dimmer_count == (100 - _dimmer_value))
     {
         _dimmer_count = 0;
         TIMSK0 &= ~(1 << OCIE0A);
@@ -259,5 +269,5 @@ ISR(TIMER0_COMPA_vect)
             break;
         }
     }
-    ++_dimmer_count;
+    TIFR0 = (1 << OCF0A);
 }