> I want to first understand how can interface a 12f629 to a
> mobile phone (hardware part is easy) download a sms message
> to the pic and then use it to trigger (for learning purposes) one
> output connected to say an LED.

I should be able to help you a fair bit, as I'm doing something
very similar using a cellular modem and an 18F4550

My project is decoding and sending SMS/emails, using AT
commands in text mode and RS232 comms with the modem

My first piece of advice would be to consider an 18F. You can
sample these free from Microchip. There are two main reasons,
both to do with string handling. Firstly, the 18F (even the F1220
or F1320 will do) have 3 FSRs, so extracting/copying parts of
the SMS and its header will be a lot easier. Also there's more
RAM, and it's contiguous, not fragmented like in previous families
such as the 16F

However, what you propose could be done with a 12F. The
meagre 64 bytes of RAM and 1 FSR would be a challenge, but
that depends on what information you want to get (and possibly
keep to use later) from the SMS. The command interpretation
side of things (eg turn a LED on) would be reasonably similar in
any PIC. My VHO is that a 12F might be a little small as the SMS
interface, but we can soon find that out for sure

Other projects like this I've seen are using a larger PIC or AVR

I started off on my project using 16F but soon changed to 18F.
Made programming so much easier, particularly, as I said, in
the string handling department. Plus, one other requirement is
USB connectivity so it had to be something like a 4550

If you can describe more fully what protocols you expect with
the or any particular phone, and what the bare essentials are, then
we can go into more detail about which PIC would be the most
suitable. For example, one with a UART will probably help

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