Specifications

SIM900 AT Commands Set
SIM900_ATC_V1.01 147 23.06.2010
Parameter
<mode> 0 Send SMS in ordinary way
1 Enable to send SMS varying from 0x00 to 0x7f except
0x1a and 0x1b under text mode and GSM character set
Reference Note
Only be available in TEXT mode and +CSCS="GSM ".
6.2.36 AT+AUTEST Audio Channel Loopback Test
AT+AUTEST Audio Channel Loopback Test
Test Command
AT+AUTEST=?
Response
+AUTEST: (0-1), (0-1)
OK
Response
OK
ERROR
Write Command
AT+AUTEST=
<state>,<type>
Parameters
<state> 0 test is off
1 test is on
<type> 0 Normal audio channel
1 AUX audio channel
Reference Note
6.2.37 AT+CCODE Configure SMS Code Mode
AT+CCODE Configure SMS Code Mode
Test Command
AT+CCODE=?
Response
+CCODE:(0,1)
OK
Response
+CCODE:<mode>
OK
Read Command
AT+CCODE?
Parameter
see Write Command
Write Command
AT+CCODE=
<mode>
Response
OK
ERROR