Hi there,

I have done a 2400 baud modem and the answer is yes you can. In fact the
slower speeds will not be supported by Telstra in future and 2400 baud may
yet be the safest bet (this applies to Australia as far as I know). The PET
(personal entry terminal) pager protocol gives the ACKs and NACKs etc
sequence you need and can be obtained from Telstra at no charge. I have
found the TDK modem module data pump IC most useful in this app being driven
by a PIC16C505 gave 2400baud half duplex with no problems. Hope this helps

                                                                John

-----Original Message-----
From: R. Michael O'Bannon [mailto:mob@MINDSPRING.COM]
Sent: Thursday, 11 May 2000 12:51
To: PICLIST@MITVMA.MIT.EDU
Subject: [OT] Sending SMS from a PIC


I've had good luck with the schematic in the recent Nuts and Volts article
that shows how to interface a PIC to a Cermetek modem module.  Thus far,
I've been able to do some simple numeric paging.  Now I'd like to experiment
with sending short message service text to my cellular phone.  Does anyone
know whether this can be done with a 2400 baud modem?  If so, where would I
find information on the protocol?  Thus far my cellular provider has been
less than helpful on the topic.

Thanks for your help.

R. Michael O'Bannon
Atlanta, GA