Marco,
        Did you read the post by Danjel ? It looks like a simpler way to go.
James

On Thursday, March 12, 1998 11:52 AM, Marco DI LEO
[SMTP:m.dileo@SISTINF.IT] wrote:
> 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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