On 6/9/2013 6:43 PM, Manu Abraham wrote:
> Hi,
>
> What's the best way to decode a rotary encoder (gray code) output,
> when the outputs of the encoder are connected to edge detectors
> both of which result in an IRQ each ?


One thing I like to do if I don't have the free ports that are edge=20
changeable is using a small external PIC chip, you can get a 8 pin chip=20
that can handle multiple  encoder and output the count on a single pin ,=20
then check the count with your main chip whenever you have the free=20
cycles. The extra chip doesn't have to have edge detectors since the=20
rotary decoding is all it will be doing.

The extra chip can keep the count for you  and the main chip can then=20
check the status of a single pin, any pin you like using a one wire=20
based communication to get the current count.
Mark

--=20
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