Unable to wake the XIAO ESP32C3 up from deep sleep with a PIR sensor

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Here is the code I used. I don’t have a DS3231 so just removed it with the #define USE_RTC.


#define USE_RTC  //!!!GR!!! - I don't have a DS3231 so just removed the code with this define.

#ifdef USE_RTC
#include <RTClib.h>
#endif  // USE_RTC

#include "driver/rtc_io.h"

// Define the DS3231 Interrupt pin (will wake-up the ESP32 - must be an RTC GPIO)
#define CLOCK_INTERRUPT_PIN GPIO_NUM_2  // Only RTC IO are allowed
#define CLOCK_PIN_MASK 1 << CLOCK_INTERRUPT_PIN

// LED for visual indication
const int ledPin = GPIO_NUM_4;

// Save how many times the ESP32 woke-up
RTC_DATA_ATTR int bootCount = 0;

#ifdef USE_RTC
// Instance for the RTC
RTC_DS3231 rtc;

// Set the alarm
DateTime alarm1Time = DateTime(2024, 12, 18, 12, 25, 0);
#endif  // USE_RTC

//!!!GR!!!
bool sleep_permitted = false;

// Method to print the reason by which ESP32 has been awaken from sleep
void print_wakeup_reason() {
  esp_sleep_wakeup_cause_t wakeup_reason;

  wakeup_reason = esp_sleep_get_wakeup_cause();

  switch (wakeup_reason) {
    case ESP_SLEEP_WAKEUP_EXT0:
      Serial.println("Wakeup caused by external signal using RTC_IO");
      break;
    case ESP_SLEEP_WAKEUP_EXT1:
      Serial.println("Wakeup caused by external signal using RTC_CNTL");
      break;
    case ESP_SLEEP_WAKEUP_TIMER:
      Serial.println("Wakeup caused by timer");
      break;
    case ESP_SLEEP_WAKEUP_TOUCHPAD:
      Serial.println("Wakeup caused by touchpad");
      break;
    case ESP_SLEEP_WAKEUP_ULP:
      Serial.println("Wakeup caused by ULP program");
      break;
    default:
      Serial.printf("Wakeup was not caused by deep sleep: %d\r\n", wakeup_reason);
      break;
  }
}

void IRAM_ATTR onAlarm() {
  Serial.println("Alarm occurred!");
}

void setup() {
  Serial.begin(115200);
  delay(2000);

  pinMode(ledPin, OUTPUT);

  //Print the wakeup reason for ESP32
  print_wakeup_reason();

  // Blink the LED when the ESP32 wakes-up
  digitalWrite(ledPin, HIGH);
  delay(1000);
  digitalWrite(ledPin, LOW);

#ifdef USE_RTC
  // Initialize the RTC
  if (!rtc.begin()) {
    Serial.println("Couldn't find RTC!");
    Serial.flush();
    while (1) delay(10);
  }

  if (rtc.lostPower()) {
    // this will adjust to the date and time at compilation
    rtc.adjust(DateTime(F(__DATE__), F(__TIME__)));
  }

  // Uncomment if you need to define the time of the RTC
  //rtc.adjust(DateTime(F(__DATE__), F(__TIME__)));

  // We don't need the 32K Pin, so disable it
  rtc.disable32K();
#endif  // USE_RTC

  // The alarm will trigger an interrupt
  pinMode(CLOCK_INTERRUPT_PIN, INPUT_PULLUP);
  attachInterrupt(CLOCK_INTERRUPT_PIN, onAlarm, FALLING);

  //!!!GR!!!
  if (esp_deep_sleep_enable_gpio_wakeup(CLOCK_PIN_MASK, ESP_GPIO_WAKEUP_GPIO_LOW) == ESP_OK) {
    Serial.println("Clock Mask : 0x" + String(CLOCK_PIN_MASK, HEX));
    sleep_permitted = true;
  } else {
    Serial.println("Clock Wake Error");
    sleep_permitted = false;
  }

#ifdef USE_RTC
  // Set alarm 1, 2 flag to false (so alarm 1, 2 didn't happen so far)
  // if not done, this easily leads to problems, as both register aren't reset on reboot/recompile
  rtc.clearAlarm(1);
  rtc.clearAlarm(2);

  // Stop oscillating signals at SQW Pin otherwise setAlarm1 will fail
  rtc.writeSqwPinMode(DS3231_OFF);

  // Turn off alarm 2 (in case it isn't off already)
  // again, this isn't done at reboot, so a previously set alarm could easily go overlooked
  rtc.disableAlarm(2);

  // Schedule an alarm
  if (!rtc.setAlarm1(alarm1Time, DS3231_A1_Minute)) {  // this mode triggers the alarm when the minutes match
    Serial.println("Error, alarm wasn't set!");
  } else {
    Serial.println("Alarm will happen at specified time");
  }
#endif  // USE_RTC

  // Increment boot number and print it every reboot
  ++bootCount;
  Serial.println("Boot number: " + String(bootCount));

  // Configure external wake-up
  //!!!GR!!! esp_sleep_enable_ext0_wakeup(CLOCK_INTERRUPT_PIN, 0);  //1 = High, 0 = Low
  // Configure pullup/downs via RTCIO to tie wakeup pins to inactive level during deepsleep.
  // The RTC SQW pin is active low
  //!!!GR!!! rtc_gpio_pulldown_dis(CLOCK_INTERRUPT_PIN);
  //!!!GR!!! rtc_gpio_pullup_en(CLOCK_INTERRUPT_PIN);

  delay(5000);
  if (sleep_permitted) {
    //Go to sleep now until an alarm fires
    Serial.println("Going to sleep in 1 second");
    delay(1000);
    esp_deep_sleep_start();
  }
}

void loop() {
  delay(5000);
  // The code never reaches the loop, because the ESP32 goes to sleep at the end of setup
  Serial.println("This will never be printed!");
}

I also add some extra timeouts.

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