[time-nuts] DDS - Cosine v. Sine LUT

[KD0GLS]

> On Jun 21, 2011, at 13:39, Chris Albertson wrote:
> 
> I used only 90 degrees of the table.
> 


Yes, as did I and most implementations, but why a cosine quarter-table instead of the more common sine?  A quick look at the data sheets (and the waveforms in the theory-of-op sections) for the two devices suggests they are clearly calling out one or the other, but without rationale regarding the choice.

.73,
Brent, KD0GLS, Minneapolis