>Can I put the micro in Sleep or idle mode and use say TOCK0
>input to accumulate pulses. Then use the watchdog time to
>wake the micro up to determine if it is time to send the
>accumulated pulses else go back to sleep ?

No the peripherals do not keep working while the CPU is asleep.

>Or, should I use an Interrupt pin and wake the micro up on
>each transition and increment the accumulated count until
>time to send ?

This is what would happen if you tried to use TOCK0 as the input, but if
just using the counter I suspect you would miss counts.

>Or, is there a better way to do this ?

I think you are on the right track, although I would have looked at one of
the nanowatt 16F devices myself. If you are already using the 18F series,
then stick with it.

-- 
http://www.piclist.com PIC/SX FAQ & list archive
View/change your membership options at
http://mailman.mit.edu/mailman/listinfo/piclist