Basic At Commands For Testing; Gsm At Commands - RDL SIM900A User Manual

Basic AT Commands for Testing

GSM AT Commands:

 TO CHECK THE MODEM:
AT ↲
OK
 TO CHANGE SMS SENDING MODE:
AT+CMGF=1
OK
 TO SEND NEW SMS:
AT+CMGS="MOBILE NO."
<MESSAGE
{CTRL+Z}
 TO RECEIVE SMS
AT+CMGD=1
AT+CMGR=1
+CMGL: 1,"REC READ","+85291234567",,"07/05/01,08:00:15+32",145,37
<MESSAGE
 PREFERRED SMS MESSAGE STORAGE:
AT+CPMS=?
+CPMS: ("SM"),("SM"),("SM")
OK
AT+CPMS?
+CPMS: "SM",19,30,"SM",19,30,"SM",19,30
 TO MAKE A VOICE CALL:
ATD9876543210;
 TO REDIAL LAST NO:
ATDL
 TO RECEIVE INCOMING CALL:
ATA ↲
 TO HANGUP OR DISCONNECT A CALL:
ATH ↲
 TO SET A PARTICULAR BAUDRATE:
AT+IPR=?
AT+IPR=0
 OPERATOR SELECTION:
AT+COPS=?
OK
AT+COPS? ↲
+COPS: 0,0,"AirTel"
OK
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↲
↲ {to delete the message in buffer}
↲ {to receive first message AT+CMGR=1}
{to receive second message AT+CMGR=2 and so on}
↲
↲
↲
↲
↲ {To view the baud rate values}
↲ {To set the modem to autobauding mode}
↲
GSM GPRS SIM900A MODEM
REV1.0
↲
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