retrolefty:
Also I've never seen this mode of passing the mode value to the attachInterrupt function. It might not be properly be setting up the mode correctly.static const int INTERRUPT_MODE = RISING;Try setting the mode directly in the attach statement:
attachInterrupt(INTERRUPT_NUMBER, beep, RISING); // or the other defined mode names.
Makes no sense to me, but I've done as you said and still does not work.