[BUG] ESP32-C3: Fix reboot/crashes on ESP32-C3s when receiving.

examples/DumbIRRepeater/DumbIRRepeater.ino

@@ -57,7 +57,12 @@
 
 // The GPIO an IR detector/demodulator is connected to. Recommended: 14 (D5)
 // Note: GPIO 16 won't work on the ESP8266 as it does not have interrupts.
+// Note: GPIO 14 won't work on the ESP32-C3 as it causes the board to reboot.
+#ifdef ARDUINO_ESP32C3_DEV
+const uint16_t kRecvPin = 10;  // 14 on a ESP32-C3 causes a boot loop.
+#else  // ARDUINO_ESP32C3_DEV
 const uint16_t kRecvPin = 14;
+#endif  // ARDUINO_ESP32C3_DEV
 
 // GPIO to use to control the IR LED circuit. Recommended: 4 (D2).
 const uint16_t kIrLedPin = 4;

examples/IRrecvDemo/IRrecvDemo.ino

@@ -24,7 +24,12 @@
 // An IR detector/demodulator is connected to GPIO pin 14(D5 on a NodeMCU
 // board).
 // Note: GPIO 16 won't work on the ESP8266 as it does not have interrupts.
+// Note: GPIO 14 won't work on the ESP32-C3 as it causes the board to reboot.
+#ifdef ARDUINO_ESP32C3_DEV
+const uint16_t kRecvPin = 10;  // 14 on a ESP32-C3 causes a boot loop.
+#else  // ARDUINO_ESP32C3_DEV
 const uint16_t kRecvPin = 14;
+#endif  // ARDUINO_ESP32C3_DEV
 
 IRrecv irrecv(kRecvPin);
 

examples/IRrecvDumpV2/IRrecvDumpV2.ino

@@ -38,7 +38,12 @@
 // An IR detector/demodulator is connected to GPIO pin 14
 // e.g. D5 on a NodeMCU board.
 // Note: GPIO 16 won't work on the ESP8266 as it does not have interrupts.
+// Note: GPIO 14 won't work on the ESP32-C3 as it causes the board to reboot.
+#ifdef ARDUINO_ESP32C3_DEV
+const uint16_t kRecvPin = 10;  // 14 on a ESP32-C3 causes a boot loop.
+#else  // ARDUINO_ESP32C3_DEV
 const uint16_t kRecvPin = 14;
+#endif  // ARDUINO_ESP32C3_DEV
 
 // The Serial connection baud rate.
 // i.e. Status message will be sent to the PC at this baud rate.

examples/IRrecvDumpV3/IRrecvDumpV3.ino

@@ -45,7 +45,12 @@
 // An IR detector/demodulator is connected to GPIO pin 14
 // e.g. D5 on a NodeMCU board.
 // Note: GPIO 16 won't work on the ESP8266 as it does not have interrupts.
+// Note: GPIO 14 won't work on the ESP32-C3 as it causes the board to reboot.
+#ifdef ARDUINO_ESP32C3_DEV
+const uint16_t kRecvPin = 10;  // 14 on a ESP32-C3 causes a boot loop.
+#else  // ARDUINO_ESP32C3_DEV
 const uint16_t kRecvPin = 14;
+#endif  // ARDUINO_ESP32C3_DEV
 
 // The Serial connection baud rate.
 // i.e. Status message will be sent to the PC at this baud rate.

examples/SmartIRRepeater/SmartIRRepeater.ino

@@ -60,7 +60,12 @@
 
 // The GPIO an IR detector/demodulator is connected to. Recommended: 14 (D5)
 // Note: GPIO 16 won't work on the ESP8266 as it does not have interrupts.
+// Note: GPIO 14 won't work on the ESP32-C3 as it causes the board to reboot.
+#ifdef ARDUINO_ESP32C3_DEV
+const uint16_t kRecvPin = 10;  // 14 on a ESP32-C3 causes a boot loop.
+#else  // ARDUINO_ESP32C3_DEV
 const uint16_t kRecvPin = 14;
+#endif  // ARDUINO_ESP32C3_DEV
 
 // GPIO to use to control the IR LED circuit. Recommended: 4 (D2).
 const uint16_t kIrLedPin = 4;

src/IRrecv.cpp

@@ -261,13 +261,20 @@ static void USE_IRAM_ATTR gpio_intr() {
 ///   capturing data. (Default: kTimeoutMs)
 /// @param[in] save_buffer Use a second (save) buffer to decode from.
 ///   (Default: false)
-/// @param[in] timer_num Nr. of the ESP32 timer to use (0 to 3) (ESP32 Only)
+/// @param[in] timer_num Nr. of the ESP32 timer to use. (0 to 3) (ESP32 Only)
+///   or (0 to 1) (ESP32-C3)
 #if defined(ESP32)
 IRrecv::IRrecv(const uint16_t recvpin, const uint16_t bufsize,
                const uint8_t timeout, const bool save_buffer,
                const uint8_t timer_num) {
-  // There are only 4 timers. 0 to 3.
-  _timer_num = std::min(timer_num, (uint8_t)3);
+  // Ensure we use a valid timer number.
+  _timer_num = std::min(timer_num,
+                        (uint8_t)(
+#ifdef SOC_TIMER_GROUP_TOTAL_TIMERS
+                                  SOC_TIMER_GROUP_TOTAL_TIMERS - 1));
+#else  // SOC_TIMER_GROUP_TOTAL_TIMERS
+                                  3));
+#endif  // SOC_TIMER_GROUP_TOTAL_TIMERS
 #else  // ESP32
 /// @cond IGNORE
 /// Class constructor
@@ -353,6 +360,13 @@ void IRrecv::enableIRIn(const bool pullup) {
   // Initialise the ESP32 timer.
   // 80MHz / 80 = 1 uSec granularity.
   timer = timerBegin(_timer_num, 80, true);
+#ifdef DEBUG
+  if (timer == NULL) {
+    DPRINT("FATAL: Unable enable system timer: ");
+    DPRINTLN((uint16_t)_timer_num);
+  }
+#endif  // DEBUG
+  assert(timer != NULL);  // Check we actually got the timer.
   // Set the timer so it only fires once, and set it's trigger in uSeconds.
   timerAlarmWrite(timer, MS_TO_USEC(params.timeout), ONCE);
   // Note: Interrupt needs to be attached before it can be enabled or disabled.

src/IRrecv.h

@@ -52,8 +52,15 @@ const uint16_t kMaxTimeoutMs = kRawTick * (UINT16_MAX / MS_TO_USEC(1));
 const uint32_t kFnvPrime32 = 16777619UL;
 const uint32_t kFnvBasis32 = 2166136261UL;
 
-// Which of the ESP32 timers to use by default. (0-3)
+#ifdef ESP32
+// Which of the ESP32 timers to use by default.
+// (3 for most ESP32s, 1 for ESP32-C3s)
+#ifdef SOC_TIMER_GROUP_TOTAL_TIMERS
+const uint8_t kDefaultESP32Timer = SOC_TIMER_GROUP_TOTAL_TIMERS - 1;
+#else  // SOC_TIMER_GROUP_TOTAL_TIMERS
 const uint8_t kDefaultESP32Timer = 3;
+#endif  // SOC_TIMER_GROUP_TOTAL_TIMERS
+#endif  // ESP32
 
 #if DECODE_AC
 // Hitachi AC is the current largest state size.