Question : How do I use a F221m Ericsson GPRS modem with a Freescale (motorola) 68HC908AP64 (HC08 Family) microcontroller.

I know how to use the serial port of the microcontroller.  But I do not know what commands to use, or in what form, to control the modem, and send TCP/IP packets over a GPRS server to a fixed IP server.

Do I simply write the AT Command to the microcontroller port?

Thank you in advance!!!!

Answer : How do I use a F221m Ericsson GPRS modem with a Freescale (motorola) 68HC908AP64 (HC08 Family) microcontroller.

Reference http://www.powertec.com.au/download/docs/UGF221m.pdf (3rd party vendor)

See my response also to your 2nd question.

Your Ericsson device supports all AT commands for GSM - see GSM 07.07 standard.
http://www.3gpp.org/ftp/Specs/archive/07_series/07.07/
( yeah I know 3gpp isn't really gsm but it's faster to find the docs on their web site and they're the same ones )
GPRS specific commands start sec. 10 .

Also your device supports SMS command set for AT as well. See GSM 07.05 for that one.

Keep in mind if you use GPRS data on that product you only get outgoing only (one-way) transmission. If you use GSM then you can do incoming and outgoing data calls, but it would probably be slower. Consider your design before deciding on GPRS.

j.m.