The GPRS communication module is controlled by terminal (e.g. H50) firmware.
The actions are mapped to 3 ~4 AT command, and one PPP process.
1. Request GSM
AT+CREG.
2. Attached to GPRS network
AT+CGATT
AT+CGDCONT
3. PPP process after *99***1#
Our module control is very simple: AT commands. The following commands flow are applicable to the MC55, MC56 and SIMCOM‘s SIM300.
Some recorded AT commands flows are...
from China Mobile‘s SIM card (in H50+ MC55(?)) generated AT-log in Shanghai, captured on
Sat morning 1am+ at 19 Jun 2010:
--------
AT : [Start-up confirmation that module will response AT command]
ATE0V1 : [disable echo, detailed responses on]
AT\Q3 [RTS/CTS hardware handshake on]
at+csq [Signal quality]
at+creg? [Network registration]
AT+CIMI [Request International Mobile Subscriber Identity (IMSI)]
AT+GSN [request International Mobile Equipment Identity (IMEI)]
at+cgatt=1 [attach the terminal to GPRS service]
at+cgatt? [Return the current GPRS service state]
at+cgdcont=1,"IP","cmnet" [Define PDP Context]
at+csq [Signal quality]
atd*99***1# [Request GPRS service]