Telit Wireless Solutions GE863 - Manual (Page 12)

GE863-GPS Software User Guide
1vv0300724 Rev. 2 - 24/01/07
2.5 Checking GSM device functionality
After a proper power on the device is ready to receive AT commands on the serial port.
Several things have to be checked in order to be sure that the device is ready to send and receive
calls and SMS:
2.5.1 Autobauding
At startup it is necessary to send an AT command to make the device set the right speed and
character format of the serial port. When this is done the device responds with OK. If no response is
received within the timeout period of 200 ms retry.
• Send command
AT<cr>
• wait
for OK response
after this initial command, it is advisable to fix the port rate, in order to eliminate possible errors in
detecting the serial speed rate:
• Send command
AT+IPR=<rate><cr>
• wait
for OK response
where rate is the port speed and can be 0, 300,1200,2400,4800,9600,19200,38400,57600,115200
bps.
If <rate> is set to 0, then automatic speed detection is enabled and also character format (see +ICF)
is set to auto-detect. (default)
If <rate> is specified and not 0, DTE-DCE speed is fixed at that speed, hence no speed auto-detection
(autobauding) is enabled.
TIP: The serial port suggested setting is: port speed 38400, character format 8N1 (8 bit per
char, No parity bit, 1 stop bit).
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