> In something realtime like this you just need to count cycles and make
> sure there won't be any surprises

Agreed. If some temporary jitter is acceptable then a DDS like you
describe would be fine and time spent in the ISR could be minimised.
With multiple interrupts or mainline code demanding attention then a
more complex isochronous approach might be necessary to avoid
excessive jitter. So, again, it comes back to time management and a
clear idea of what needs to be accomplished in the ISR, what needs
to be accomplished in the mainline code, how those two could affect
each other and so on

Which way Cristiano does it depends very much on what his specs and
expectations are

wbr
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