Specifications
SIM900 AT Command Manual       
SIM900_AT Command Manual_V1.03  47  12/24/2010 
OK 
ERROR 
If error is related to ME functionality: 
+CME ERROR: <err> 
Parameters 
<mode> 0 Query CCM value 
  1 Deactivate the unsolicited reporting of CCM value 
  2 Activate the unsolicited reporting of CCM value 
<ccm>  String type (string should be included in quotation marks); 
three bytes of the current CCM value in hex-decimal format 
(e.g. "00001E" indicates decimal value 30); bytes are 
similarly coded as ACMmax value in the SIM 
   000000-FFFFFF 
Reference 
GSM 07.07 [13] 
Note 
3.2.4 AT+CBST Select Bearer Service Type 
AT+CBST Select Bearer Service Type 
Response 
+CBST: (list of supported <speed>s),(list of supported <name>s),(list of 
supported <ce>s) 
OK 
Test Command 
AT+CBST=? 
Parameters 
See Write Command 
Response 
+CBST: <speed>,<name>,<ce> 
OK 
Read Command 
AT+CBST? 
Parameters 
See Write Command 
Response 
TA selects the bearer service <name> with data rate <speed>, and the 
connection element <ce> to be used when data calls are originated. 
OK 
ERROR 
Write Command 
AT+CBST=<spee
d>[,<name>[,<ce
>]] 
Parameters 
<speed> 0 Auto-bauding (automatic selection of the speed; this 










