Tutorial: Using Comparator Interrupts with the Arduino at the example of a Microphone
This tutorial was developed for the MAKE course at the University of South Florida (www.makecourse.com). It discusses the use of comparator interrupts with the Arduino. Comparator interrupts allow the triggering of interrupts based on analog voltage level thresholds. This makes them useful for detecting non-digital events, such as the output from a microphone. By using an external reference voltage generated with the Arduino, it is possible to select the sound level at which the interrupt is being triggered. The tutorial also introduces to 'condenser microphones', i.e. microphones that are based on the change of a capacitance due to sound pressure.
