Table of Contents
Advertisement
DTE to Modem Modem to DTE
#VTX
CONNECT
<Data>
<DLE><ETX>
VCON
#VBT=12
OK
#VTS=#
OK
#VBS=4
OK
#VRX
CONNECT
<Data>
<DLE>b
X
<DLE><ETX>
VCON
H
1048
AT Command Reference Manual
Table 7-9. Answer Call/Play Greeting/Record Message [Cont'd]
The DTE does not wait for any tones, and tells the modem that it is ready to send a
voice greeting at the current compression and sampling settings (4-bit/7200).
The modem tells the DTE that it can now send data. The modem enters Voice
Transmit Mode and DTMF monitoring is still enabled as well as the ADPCM data flow.
The DTE sends greeting message data. The modem waits up to 1 second or until
XOFF threshold is reached before starting to transmit to ensure uninterrupted data
flow. If the voice transmit buffer runs empty, the transmission is disabled.
The DTE has finished with its transmission, and now instructs the modem to enter
Online Voice Command Mode since this is the telephone line.
The modem tells the DTE it is done. If the DTE sends the <DLE><ETX> before the
modem has finished transmitting all the data in its voice transmit buffer, the DTE must
wait for this response.
The DTE requests that DTMF digits be sent as "beeps" with the #VTS command while
in Online Voice Command Mode, with each "beep" having a duration of 1.2 seconds.
The modem confirms command reception
The DTE sends a "BEEP" to annotate its greeting message. This beep is a 1.2 second
long DTMF #. During this period, the no abort is possible from the DTE, and should not
be necessary.
After the modem sends the "BEEP", it sends OK to inform the DTE that it is ready to
move on. DTMF pass through is re-enabled.
The DTE asks for 4-bit compression to recorded message. The DTE needs to work at
38,400 bps since after start and stop bits are added the speed increases to 36,000
bps.
The modem is configured for 4-bit compression.
The DTE instructs the modem to turn the line around and begin recording a message
from the remote.
The modem sets things up and enables ADPCM data transfer to the DTE with the
current silence detection sensitivity setting.
ADPCM data is shipped to the DTE with shielded DTMF tones folded in. The modem is
looking for silence, busy, dial tone, and loop break. The DTE records everything in its
storage media.
The caller has finished, hung up, and in this case, a busy cadence was detected before
anything else such as expiration of the #VSP silence detection period.
The DTE uses a key abort to respond to a busy detection.
The modem is now in Online Voice Command Mode.
DTE sends modem to #CLS=0 with #BDR=0.
Description and Interpretation
7-37
Advertisement
Table of Contents
