Multi-Tech Systems GPRS (MTMMC-G) ユーザーズマニュアル

Chapter 5 – Call Control Commands 

Multi-Tech Systems, Inc. Wireless GSM/GPRS AT Commands (Document Number S000293I) 

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Syntax:   

AT+VTD=<n> 

AT+VTD=6 
Note: To define 600 ms tone duration  

OK 
Note: Command valid  

AT+VTD=0 
Note: To set the default value (70 ms 

± 5 ms) 

OK 
 

AT+VTD? 
Note: Query current tone duration 

AT+VTD: <n> 
OK 

AT+VTD=? AT+VTD: 

<0-255> 

OK 

 

The product enables the user application to send DTMF tones over the GSM network. This command 
enables tones to be transmitted only when there is an active call. 

 

 

  DTMF tone to transmit.  

Tone is in {0-9, *, #, A, B, C, D} 

Syntax:   

Command Syntax: AT+VTS=<Tone> 

AT+VTS=A 
 

OK 
Note: Command valid  

AT+VTS=11 
Note: To set the default value  

+CME ERROR: 3 
Note: If the <Tone> is wrong 

AT+VTS=4 
 

+CME ERROR: 3 
Note: If there is no communication 

AT+VTS=”1”;+VTS=”3”;+VTS=”#” 
OK 
Note: Sed tone sequence 13# 

 

 

 

This command redials the last number used in the ATD command. The last number dialed is displayed 
followed by “;” for voice calls only. 

Values:  

No parameters

Syntax:  ATDL 

ATDL 
Note: Redial last number 

0146290800; 
OK 
Note: Last call was a voice call. Command valid