On Mon, Mar 8, 2010 at 11:03 PM, William "Chops" Westfield wrote: > > On Mar 8, 2010, at 1:25 PM, Brendan Gillatt wrote: > >> Other options are bit-banged PWM--again with a lowpass >> filter--or an external DAC chip. > > With the PICs relatively strong output drivers, you can also think > about using a set of resistors attached to some digital pins... > > BillW > I did this to make a 40kHz arbitrary waveform generator for an ultrasound application. It worked pretty well. I matched the resistors so that the linearity was pretty good. Follow it up with a lowpass filter and you're good to go. -- Martin K. -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist