Sleep Interupt Voltages 0.11 to 4.56??

Projects Programming
6

  1. Only interrupt modes LOW and HIGH are guaranteed to wake the device up from sleep mode.

  2. If the PIR pulls the input low for a short while before letting it go high again, the mcu will wake up from sleep mode but will not execute the ISR.

  3. Never do a Serial.print from an ISR.

I suggest you make the following changes to your code:

  1. Use interrupt mode LOW instead of CHANGE.

  2. Move the Serial.println("Woke Up") line into loop(), immediately after the sleep call.

  3. Have the ISR do a detachInterrupt and nothing else.