Has anyone here used the DDS method to generate sinewaves with a PIC?
We used a 16c74 running at 8MHz to generate 1Hz to 2000Hz in 1 Hz
steps. Great for the original application but now we want to ramp up
to 20kHz in 1 Hz steps but we just cant squeeze enough for 20kHz out
of the code (now a 16MHz xtal). Has anyone done this?  Some clues for
tight code?... please.