Silicon Laboratories SI2493/57/34/15/04 - Manual (Page 211)

AN93
Rev. 1.3 211
AT+VGT=128 OK
Set the RS232-to-DAA transmit gain regis-
ter (UB3) for TAM PSTN.
AT+VSD=129 OK
Set sensitivity level for ICM recording
silence detection.
AT+VSM=4 OK
Select G.711U
-law PCM, 8-bit, 64 kbps
format. The voice driver will need to track
the OGM format with the OGM PCM file.
AT+VLS=0 OK
Disable voice mode. Used as a transition
point between non-zero +VLS voice
modes.
AT+VLS=15 OK
Setup off-hook voice to PSTN. See
Table 117 on page 190
for details.
AT+VTX CONNECT Trigger transmit operation.
TX Underrun. Appears at the start of +VTX
before transmit data are seen.
[Voice Stream]
Transmit OGM voice stream. During voice
stream capture, the user can adjust the
UB3 value via the and
commands. The host voice
driver will need track the number of adjust-
ments and update the +VGT value for
future use.
<~>
<1>
DTMF 1 digit detected.
<~>
<2>
DTMF 2 digit detected.
<~>
<3>
DTMF 3 digit detected.
<~>
<4> DTMF 4 digit detected. The password of
1234 has been matched. Abort answer
sequence.
OK
Terminate the transmit operation. The
modem will respond with OK to denote the
return to command mode.
Table 132. TAM PSTN Interrupted Answer – OGM Playback with DTMF Menu Entry (Continued)
Host to Modem Commands / Data
Modem to Host Result
Codes/Data
Local Modem Actions