Manual
SIM900 AT Command Manual       
SIM900_AT Command Manual_V1.03  81  12/24/2010 
Response 
TA reports one or more lines of information text which permit the user to 
identify the version, revision level or data or other information of the 
device. 
Revision:<Revision Id> 
OK 
Execution 
Command 
AT+FMR 
Parameter 
<Revision Id> the version, revision level or data or other information 
of the device. 
Reference 
EIA/TIA-578-D 
Note 
3.2.40 AT+VTD Tone Duration 
AT+VTD Tone Duration 
Response 
+VTD: (list of supported <n>s) 
OK 
Test Command 
AT+VTD=? 
Parameter 
See Write Command 
Response 
+VTD: <n> 
OK 
Read Command 
AT+VTD? 
Parameter 
See Write Command   
Response 
This Command refers to an integer <n> that defines the length of tones 
emitted as a result of the +VTS Command. This does not affect the D 
Command. 
OK 
Write Command 
AT+VTD = <n> 
Parameter 
<n> 1-255 duration of the tone in 1/10 seconds 
Reference 
GSM 07.07 [13] 
Note 
3.2.41 AT+VTS DTMF and Tone Generation 
AT+VTS DTMF and Tone Generation 
Test Command 
AT+VTS=? 
Response 
+VTS: (list of supported <dtmf>s), ,(list of supported <duration>s)  










