James & Ili wrote:
> My idea is to have an interrupt on the start
> bit, then load the timer with some value and wait for it to time out
> and generate another interrupt at which time I can check the data
> line again to get the bit in. Then reset the timer with another
> value.. etc... Is it possible to have one interrupt more or less
> inside another interrupt? If so is there anything special that needs
> to be done?

Strange... I am taking the same approach for the same problem...
I don't think that you have to worry about an interrupt inside an
interrupt.
Just try to do this:
1. set the interrupt on the start bit and wait (do your main task)
2. when you receive the interrupt on pin change disable it, set the
timer interrupt to expire in the middle of the first bit and return to
your main
3. when the timer expire, sample the bit value, set the timer interrupt
for the next bit and, again, return from interrupt
4. repeat step 3 for each bit you expect
5. goto step 1

As you can see you don't have an int in a int but just a sequence of
interrupt one after the other.

Good luck
   Marco

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Marco DI LEO                  email: m.dileo@sistinf.it
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