Chapter 9 – Short Messages Commands
Multi-Tech Systems, Inc. Wireless GSM/GPRS AT Commands (Document Number S000293I) 76
Description: The +CMGW command specifies a location in the SMS or Flash memory for the next SMS to be stored
when the +CMGW indicates a message is ready to be stored. The defined location is used only once:
+WMGO has to used again to perform another overwrite.
Important Notes:
• If the external application specifies a free location and an incoming message is received before the
AT+CMGW command occurs, the product may store the incoming message at the specified available
location. If the user then issues an AT+CMGW command without changing the location with another
AT+WMGO, the received message will be overwritten.
• The location number is not kept over a software reset.
Values: <loc> Location number of the SIM record to write or overwrite. The number depends on the SIM or
Flash memory capacity.
Syntax: Command Syntx: AT+WMGO= <loc>
Command Possible responses
AT+CPMS?
Note: Check the storage area +CPMS: “SM”,3,10,”SM”,3,10,”SM”,3,10
AT+CMGW=”+33146290800”<CR>
Hello how are you?<ctrl-Z>
Note: Write a message in text mode
+CMGW: 4
OK
Note: Message stored in index 4 in the SIM
AT+WMGO=? +WMGO: (1-10)
OK
Note: Possible values for the SIM
AT+WMGO=4
AT+CMGW=”+33146299704”<CR>
You are overwritten<ctrl-Z>
+CMGW: 4
OK
Note: New Message stored in index 4
AT+WMGO? +WMGO: 4
OK
Note: The value was used, so re-initialization
AT+WMGO=4 OK
AT+CPMS=”SM”,”ME,””SM” +CPMS: 3,10,0,99,3,10
OK
Note: Change the storage area from SIM to Flash
AT+WMGO? +WMGO: (1-99)
OK
Note: Possible values for Flash
AT+WMGO? +WMGO: 0
OK
Note: We changed the storage area, so the value
was reinitialized
AT+WMGO=999 +CMS ERROR: 321
Note: If the storage area is changed with the AT+CPMS command, the value of WMGO will be reset to
zero.