> Looking for how to do this on a 18F4550 Joe, there's an example of how to do this with the 18F67J10 http://ww1.microchip.com/downloads/en/AppNotes/00643c.pdf I've not tried it myself. Been reading that AN to use just the ADPCM section with a dsPIC audio DAC, not PWM Joe --=20 http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .