Added ESP32 IR receive support (IRsend not implemented yet).

- disable a lot of defines not relevant to ESP32, set them to 1 (no-op)
- change default IR pin to 35 from 11
- changed serial speed to 115200 (9600 is too slow to keep up with IR input)
- irSend disables code that will not compile on ESP32. It won't work,
  but it won't break compilation either.

Author: marcmerlin

IRremote.cpp

@@ -18,7 +18,9 @@
 // Whynter A/C ARC-110WD added by Francesco Meschia
 //******************************************************************************
 
+#ifndef ESP32
 #include <avr/interrupt.h>
+#endif
 
 // Defining IR_GLOBAL here allows us to declare the instantiation of global variables
 #define IR_GLOBAL
@@ -120,7 +122,11 @@ int  MATCH_SPACE (int measured_ticks,  int desired_us)
 // As soon as first MARK arrives:
 //   Gap width is recorded; Ready is cleared; New logging starts
 //
+#ifdef ESP32
+void onTimer()
+#else
 ISR (TIMER_INTR_NAME)
+#endif
 {
 	TIMER_RESET;
 

boarddefs.h

@@ -39,6 +39,10 @@
 #	define BLINKLED_ON()   (PORTD |= B00000001)
 #	define BLINKLED_OFF()  (PORTD &= B11111110)
 
+#elif defined(ESP32)
+#	define BLINKLED        255
+#	define BLINKLED_ON()   1
+#	define BLINKLED_OFF()  1
 #else
 #	define BLINKLED        13
 	#define BLINKLED_ON()  (PORTB |= B00100000)
@@ -147,12 +151,21 @@
 //
 #if defined(IR_USE_TIMER2)
 
+#ifdef ESP32 // Used in irSend, not implemented yet (FIXME)
+#define TIMER_RESET	    1
+#define TIMER_ENABLE_PWM    1
+#define TIMER_DISABLE_PWM   Serial.println("IRsend not implemented for ESP32 yet");
+#define TIMER_ENABLE_INTR   1
+#define TIMER_DISABLE_INTR  1
+#define TIMER_INTR_NAME     1
+#else
 #define TIMER_RESET
 #define TIMER_ENABLE_PWM    (TCCR2A |= _BV(COM2B1))
 #define TIMER_DISABLE_PWM   (TCCR2A &= ~(_BV(COM2B1)))
 #define TIMER_ENABLE_INTR   (TIMSK2 = _BV(OCIE2A))
 #define TIMER_DISABLE_INTR  (TIMSK2 = 0)
 #define TIMER_INTR_NAME     TIMER2_COMPA_vect
+#endif
 
 #define TIMER_CONFIG_KHZ(val) ({ \
 	const uint8_t pwmval = SYSCLOCK / 2000 / (val); \

examples/IRrecvDemo/IRrecvDemo.ino

@@ -8,16 +8,22 @@
 
 #include <IRremote.h>
 
+#ifdef ESP32
+int RECV_PIN = 35;
+#else
 int RECV_PIN = 11;
+#endif
 
 IRrecv irrecv(RECV_PIN);
 
 decode_results results;
 
 void setup()
 {
-  Serial.begin(9600);
+  Serial.begin(115200);
+  Serial.println("Enabling IRin");
   irrecv.enableIRIn(); // Start the receiver
+  Serial.println("Enabled IRin");
 }
 
 void loop() {

examples/IRrecvDump/IRrecvDump.ino

@@ -15,15 +15,19 @@
 *  You can change this to another available Arduino Pin.
 *  Your IR receiver should be connected to the pin defined here
 */
-int RECV_PIN = 11; 
+#ifdef ESP32
+int RECV_PIN = 35;
+#else
+int RECV_PIN = 11;
+#endif
 
 IRrecv irrecv(RECV_PIN);
 
 decode_results results;
 
 void setup()
 {
-  Serial.begin(9600);
+  Serial.begin(115200);
   irrecv.enableIRIn(); // Start the receiver
 }
 

examples/IRrecvDumpV2/IRrecvDumpV2.ino

@@ -6,15 +6,15 @@
 //------------------------------------------------------------------------------
 // Tell IRremote which Arduino pin is connected to the IR Receiver (TSOP4838)
 //
-int recvPin = 11;
+int recvPin = 35;
 IRrecv irrecv(recvPin);
 
 //+=============================================================================
 // Configure the Arduino
 //
 void  setup ( )
 {
-  Serial.begin(9600);   // Status message will be sent to PC at 9600 baud
+  Serial.begin(115200);   // Status message will be sent to PC at 9600 baud
   irrecv.enableIRIn();  // Start the receiver
 }
 

irRecv.cpp

@@ -1,5 +1,10 @@
 #include "IRremote.h"
 #include "IRremoteInt.h"
+
+#ifdef ESP32
+hw_timer_t *timer;
+void onTimer(); // defined in IRremote.cpp
+#endif
 
 //+=============================================================================
 // Decodes the received IR message
@@ -117,6 +122,15 @@ IRrecv::IRrecv (int recvpin, int blinkpin)
 //
 void  IRrecv::enableIRIn ( )
 {
+// Interrupt Service Routine - Fires every 50uS
+#ifdef ESP32
+	// 3 timers, choose #1, 80 divider nanosecond precision, 1 to count up
+	timer = timerBegin(1, 80, 1);
+	timerAttachInterrupt(timer, &onTimer, 1);
+	// every 50ns, autoreload = true
+	timerAlarmWrite(timer, 50, true);
+	timerAlarmEnable(timer);
+#else
 	cli();
 	// Setup pulse clock timer interrupt
 	// Prescale /8 (16M/8 = 0.5 microseconds per tick)
@@ -130,6 +144,7 @@ void  IRrecv::enableIRIn ( )
 	TIMER_RESET;
 
 	sei();  // enable interrupts
+#endif
 
 	// Initialize state machine variables
 	irparams.rcvstate = STATE_IDLE;

irSend.cpp

@@ -54,6 +54,8 @@ void  IRsend::space (unsigned int time)
 //
 void  IRsend::enableIROut (int khz)
 {
+// FIXME: implement ESP32 support
+#ifndef ESP32
 	// Disable the Timer2 Interrupt (which is used for receiving IR)
 	TIMER_DISABLE_INTR; //Timer2 Overflow Interrupt
 
@@ -66,6 +68,7 @@ void  IRsend::enableIROut (int khz)
 	// CS2  = 000: no prescaling
 	// The top value for the timer.  The modulation frequency will be SYSCLOCK / 2 / OCR2A.
 	TIMER_CONFIG_KHZ(khz);
+#endif
 }
 
 //+=============================================================================