Lpc2000

>In terms of performance, I'd be surprised if you used up more than 2
>or 3% of the CPU to do the actual counting (assuming 10s of MHz as a
>clock rate for the processor). The counting can be done in a single
>timer interrupt, without interfering with anything else going on.

Well, my plan was to use the timer at 0.9 mil sec (max freq being 1Khz), and
average out the reading at 100 mil sec, so that I don't over flow the 8 bit
counter.
I will also count rising and falling edges so that accuracy would be still
better.
I can not increase 100 mil sec reading period, as the value is used in
another control loop
for controlling speed of variable freq. drive.

In short the application is 4 channel variable ratio electronic  gear box.


Best Regards,

Mukund Deshmukh.
Beta Computronics Pvt Ltd
10/1, IT Park, Parsodi,
Nagpur-440022
Cell - 9422113746