Jim, many thanks. As you already noticed I'm a beginner...
I'll try what you suggest and let you all know the results.

Regards,
             Caro.

On 5/25/07, PAUL James <James.Paul@colibrys.com> wrote:
>
> Carolina,
>
> Just do a comparison of what you receive versus the Ascii code for "a".
> You can do this several ways,
> But I would subtract one from the other, and then check the "Z" flag in
> the STATUS register.  If after
> The subtraction, the "Z" flag is a "1", they are the same and you have
> indeed received an "a".  If the
> "Z" flag is not a "1", then you have received something other than an
> "a", so you can continue what you
> Were doing.  Hope this helps.
>
>
>
> Regards,
>
>
> Jim
>
> -----Original Message-----
> From: piclist-bounces@mit.edu [mailto:piclist-bounces@mit.edu] On Behalf
> Of Carolina Dieguez
> Sent: Friday, May 25, 2007 2:57 PM
> To: piclist@mit.edu
> Subject: [PIC]
>
> A Visual Basic Application is sending to my PIC circuit a string 'a'.
> How can I recognize letter 'a' is being received by my PIC 16F873A??
>
> Can my PIC read strings or identify this "a" in another way?
>
> I need to know whether I'm receiving an "a" because if this is so, I
> must enable an interruption.
>
> Many thanks in advace for your help and support.
>
> Carolina.
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