Strange behaviour using interrupts

Projects Programming
13

buffer_overfly:
New code. Now the ISR only toggles a var. Still does not work.

static const int INTERRUPT_NUMBER = 0;

static const int INTERRUPT_MODE = LOW;
static int mustBeep = 0;

void setup() {
 attachInterrupt(INTERRUPT_NUMBER, requestBeep, INTERRUPT_MODE);
}

void loop() {  
 if(mustBeep){
   mustBeep = 0;
   beep();
 }
}

void beep(){
 noTone(7);
 tone(7, 440, 1000);
}

//ISR. Must take no parameters and return nothing.
void requestBeep(){
 mustBeep = 1;
}

Again don't use LOW mode, it's a snake pit, use FALLING.