Created Blinker Class

Generic blinking class for LEDs that uses Alarm Timer interrupts that work in background.  Will be used to replace and extend HAP blinking of Builtin_LED to convey status of HomeSpan at varioud points in the code.

src/Blinker.cpp

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+
+#include <Arduino.h>
+#include "Blinker.h"
+
+////////////////////////////////
+//         Blinker            //
+////////////////////////////////
+
+Blinker::Blinker(int pin, int timerNum){
+  this->pin=pin;
+  pinMode(pin,OUTPUT);
+  digitalWrite(pin,0);
+
+  group=((timerNum/2)%2==0)?TIMER_GROUP_0:TIMER_GROUP_1;
+  idx=(timerNum%2==0)?TIMER_0:TIMER_1;  
+
+  timer_config_t conf;
+  conf.alarm_en=TIMER_ALARM_EN;
+  conf.counter_en=TIMER_PAUSE;
+  conf.intr_type=TIMER_INTR_LEVEL;
+  conf.counter_dir=TIMER_COUNT_UP;
+  conf.auto_reload=TIMER_AUTORELOAD_EN;
+  conf.divider=8000;                      // 80 MHz clock / 8,000 = 10 kHz clock (0.1 ms pulses)
+
+  timer_init(group,idx,&conf);
+  timer_isr_register(group,idx,Blinker::isrTimer,(void *)this,0,NULL);
+  timer_enable_intr(group,idx);
+
+}
+
+void Blinker::isrTimer(void *arg){
+
+  Blinker *b=(Blinker *)arg;
+  
+  if(b->group){
+    if(b->idx)
+      TIMERG1.int_clr_timers.t1=1;
+    else
+      TIMERG1.int_clr_timers.t0=1;
+  } else {
+    if(b->idx)
+      TIMERG0.int_clr_timers.t1=1;
+    else
+      TIMERG0.int_clr_timers.t0=1;    
+  }
+
+  if(!digitalRead(b->pin)){
+    digitalWrite(b->pin,1);
+    timer_set_alarm_value(b->group,b->idx,b->onTime);
+    b->count--;
+  } else {
+    digitalWrite(b->pin,0);    
+    if(b->count){
+      timer_set_alarm_value(b->group,b->idx,b->offTime);
+    } else {
+      timer_set_alarm_value(b->group,b->idx,b->delayTime);
+      b->count=b->nBlinks;      
+    }
+  }
+  
+  timer_set_alarm(b->group,b->idx,TIMER_ALARM_EN);
+}
+
+void Blinker::start(int period, float dutyCycle){
+
+  start(period, dutyCycle, 1, period-dutyCycle*period);
+}
+
+void Blinker::start(int period, float dutyCycle, int nBlinks, int delayTime){
+
+  period*=10;
+  onTime=dutyCycle*period;
+  offTime=period-onTime;
+  this->delayTime=delayTime*10;
+  this->nBlinks=nBlinks;
+  count=nBlinks;
+  timer_set_counter_value(group,idx,0);
+  timer_set_alarm_value(group,idx,0);  
+  timer_start(group,idx);
+}
+
+void Blinker::stop(){
+  timer_pause(group,idx);  
+}

src/Blinker.h

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+
+#include <driver/timer.h>
+
+////////////////////////////////
+//         Blinker            //
+////////////////////////////////
+
+class Blinker {
+  
+  timer_group_t group;
+  timer_idx_t idx;
+  int pin;
+
+  int nBlinks;
+  int onTime;
+  int offTime;
+  int delayTime;
+  int count;
+
+  static void isrTimer(void *arg); 
+
+  public:
+
+  Blinker(int pin, int timerNum=0);
+
+//  Creates a generic blinking LED on specified PIN controlled
+//  in background via interrupts generated by an ESP32 Alarm Timer.
+//
+//  pin:         Pin mumber to control.  Blinker will set pinMode to OUTPUT automatically 
+//  timerNum:    ESP32 Alarm Timer to use. 0=Group0/Timer0, 1=Group0/Timer1, 2=Group1/Timer0, 3=Group1/Timer1
+    
+  void start(int period, float dutyCycle=0.5);
+    
+//    Starts simple ON/OFF blinking.
+//
+//    period:      ON/OFF blinking period, in milliseconds
+//    dutyCycle:   Fraction of period that LED is ON (default=50%)
+
+  void start(int period, float dutyCycle, int nBlinks, int delayTime);
+
+//    Starts ON/OFF blinking pattern.
+//
+//    period:      ON/OFF blinking period, in milliseconds, used for blinking portion of pattern
+//    dutyCycle:   Fraction of period that LED is ON (default=50%)
+//    nBlinks:     Number of blinks in blinking portion of pattern
+//    delayTime:   delay, in milliseconds, during which LED is off before restarting blinking pattern
+
+
+  void stop();
+
+//    Stops current blinking pattern.
+
+};