Olin Lathrop ha scritto:
> You do if you want good noise immunity.

ok


> Take a look at the cycles though.  Compared to a 24F at anything near full
> speed, the cycles used by this is a tiny fraction.  Let's say for example
> the PIC is running at 30MHz instruction rate.  That's 30K instructions per
> 1mS sample.  1% of that would be 300 instruction, which is way more than the
> filtering and peak detection would take.  Are you really so tight on CPU
> cycles that a fraction of 1% makes a difference?

I have some other interrupts going on - I posted a thread @ forum but 
was going to replicate it in here. Basically I have an underlying 
Ethernet or USB app going on (or even none of them - simplest case), a 
text LCD and some simple keys; and I have dimmer going on (zero-crossing 
plus 100uS steps for triggering the Triac), and a FM-out which is 
basically a 1000-2000 Hz sine-wave that I plan on doing using a HW PWM 
and a 16 step sine-table. This calls for a total of:

1KHz IRQ for RMS
10KHz IRQ for dimmer
32KHz IRQ for the 16step sine-wave @2KHz

Should be definitely doable, but of course I want to do it "best I can" :)
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