next topic »

[on:]

Code:

#include <avr/sleep.h>

void setup(){
  // disable ADC
  ADCSRA = 0; 
  pinMode(2,INPUT);
  attachInterrupt (0, gotoSleep, RISING);
  Serial.begin(9600);
  Serial.println("reset");
}

void loop(){

 
}

void gotoSleep(){
  Serial.println("gotoSleep");
  detachInterrupt (0);
  attachInterrupt (0, wake, RISING);
  set_sleep_mode (SLEEP_MODE_IDLE); 
  sleep_enable();
  sleep_cpu ();
 detachInterrupt (0);
 attachInterrupt (0, gotoSleep, RISING);
}

void wake(){
  Serial.println("wake");
  sleep_disable();
}

This simply doesn't work for me and I don't know why. After "reset", serial wont print anything. I have a multimeter hooked up to it so I know it's not going to sleep. I can get it to sleep fine if I put the sleep stuff in the setup. But if I comment out all of the sleep and interrupt lines in the gotoSleep function, it calls gotoSleep just fine when I press the button.

I must be missing something very obvious.

[Reply #1 on:]

You can't do Serial.print() in an ISR. Serial output requires interrupts, which are disabled in an ISR.

Both of your ISRs have Serial.print() statements. They have to go.

[Reply #2 on:]

Ah, ok my problem first was that I didn't realize I was using "IDLE" so I wasn't getting the multimeter readings I was expecting. Then I added the serial out to double check and like you said, that doesn't work. I changed it to power down and everything it behaving now. Thanks.

[Reply #3 on:]

I'd do Serial.flush() and Serial.end() before sleeping, and Serial.begin() after waking up.