Technics MT5634SMI-34 AT+VLS=4, At+Vtx, Dle Etx, AT+VLS=0, AT+VIT=0 +VPR=0 +FCLASS=0, AT+FCLASS=8

	Chapter 6 – Voice Commands
AT+VLS=4	The modem selects the speaker. The modem had earlier reported that a speaker was
	available.
OK	The modem agrees.
AT+VTX	The PC selects the Voice Transmit mode.
CONNECT	The modem agrees.
<Data>	The PC delivers <DLE> shielded and silence compressed voice data across the
	PC/modem interface.
<DLE> <ETX>	The PC indicates the end of the Voice data stream.
OK	The modem indicates it is in Voice Command mode.
AT+VLS=0	The PC deselects all devices.
OK	The modem agrees.
	The PC switches to Data mode, Command mode, and autobauding enabled:
	AT+VIT=0; +VPR=0; +FCLASS=0
OK	The modem agrees.

Answer Phone, Play Greeting Message, and Record Message Example

Command	Response
AT+FCLASS=8;	The DCE switches to Voice mode. The DTE selects a fixed
AT+VIT=60;	DTE-DCE interface rate. The DTE knows from the sample
+VPR=16	rate selected earlier and the bits-per-sample that the DTE-DCE interface rate should be
	38400 bps. The DTE-DCE Inactivity Timer starts with 60 seconds.
OK	DCE agrees (to the old DTE/DCE interface rate).

AT+VSM=129, 7200, 0, 0 DTE changes its DTE/DCE rate to 38400 bps and selects a compression method with the least sensitive setting, with the goal of recording a message with less distortion, and at 7200 samples per second. Assume that the DTE issued a +VSM=? command earlier.

OK	The DCE agrees.
AT+VSD=127, 20	DTE selects a silence detection period of 2 seconds.
AT+VLS=0	DTE selects a silence detection period of 2 seconds with the least sensitive setting (for
	detecting the end of voice recording).
OK	The DCE agrees.
AT+VIT=0;	The DTE selects the Data mode with autobauding, and disables +VPR=0; automatic DCE
	answering. The DCE waits for a phone call.
+FCLASS=0	(not necessarily in Data mode).
S0=0
OK	The DCE agrees.
RING	At some time, a remote station calls.
AT+FCLASS=8;	The DCE switches to Voice mode. The DCE selects a fixed AT+VIT=60; DTE/DCE
	Interface Rate. The DTE knows from the sample AT+VPR=16; rate selected earlier and
	the bits per sample that the DTE/DCE Interface Rate should be 38400 baud. The
	DTE/DCE Inactivity Timer starts with a value of 60 seconds.
OK	The DCE agrees (at the old DTE/DCE Interface Rate).
AT+VLS=0	The DTE selects all devices.
OK	The DCE agrees.
AT+VIT=0;	The DTE selects Data mode/Command mode with
+VPR=0;	autobauding, and disables automatic DCE answering. The +FCLASS=0; DCE waits for a
S0=0	phone call (not necessarily in Data mode).
AT+FCLASS=8;	The DCE switches to Voice mode. The DCE selects a fixed DTE/DCEAT+VIT=60;
AT+VPR=16;	Interface Rate. The DTE knows from the sample rate selected earlier and the bits per
	sample that the DTE/DCE Interface Rate should be 38400 baud. The DTE/DCE Inactivity
	Timer starts with a value of 60 seconds.
OK	The DCE agrees (at the old DTE/DCE Interface Rate).
<DLE> <R>	The DCE selects another ring (at 38400 bps).

SocketModem Global MT5634SMI Developer’s Guide 63