DDS (generating sine waves) with onboard DAC using latest PIC 16F chips?

[HankMcSpank]

oops, henrik nailed it just a few posts back...

However, don't forget how this works.... The lookup table is 256 entries long. At 500Hz output frequency you would need an interrupt rate of 500*256=128kHz to "hit" every entry in the table (thus producing the highest possible quality output). As the frequency goes up more and more of the table entries are skipped, you might "hit" entry 5, 75, 145, 205, 29, 9, 169, 239, 53, 123,193, 7 and so on. Plotting those values and drawing a straight line between them isn't going to produce a very pretty sine-wave.

So I guess the way to get the interrupt rate down is to shorten the length of the lookup table.

I think I need to step away from this for a little while my brain is frazzled!