print wakeup reason

cubesatsim/esp32-cam-send-jpeg-serial/esp32-cam-send-jpeg-serial.ino

@@ -174,6 +174,21 @@ void deleteFile(fs::FS &fs, const char * path) {
   }
 }
 
+void print_wakeup_reason(){  // from https://randomnerdtutorials.com/esp32-deep-sleep-arduino-ide-wake-up-sources/ 
+  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\n",wakeup_reason); break;
+  }
+}
+
 void setup() {
 
 //  delay(5000);  
@@ -242,6 +257,7 @@ void setup() {
     delay (100); // Wait 0.1 sec
     digitalWrite(LED_PIN, HIGH); // Turn off         
         
+    print_wakeup_reason();    
 }
 
 void loop() {