Rockwell RCV144ACx, Справочник по командам

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AT Command Reference Manual
1048 7-41
Table 7-12. Adaptive Fax/Data/Voice; Determine Data
DTE to Modem Modem to DTE Description and Interpretation
RING Sometime later, we receive a call.
#CLS=8 Configure the modem for Voice Mode (still ADPCM).
OK The modem agrees, and is now set up for voice, but the DTE can change things during
the discrimination phase.
#BDR=16 The DTE knows that the compression requires a 38,400 bps speed, so it forces this as
the new speed.
OK This OK message is sent at 9600 bps, but the modem then switches to 38,400 bps.
The S30 timer is now active.
#VSS=2 Sets silence detection sensitivity to midrange.
OK The modem confirms command reception.
A The DTE answers. (Note that this is where the DTE can let another RING go by to
process Caller ID.)
VCON The modem is now in Online Voice Command Mode. DTMF and calling tone detection
is enabled. If fax or data calling tones are detected, the DTE can change to Fax or
Data Mode.
#VTX The DTE immediately switches to Voice Transmit Mode to send out a short greeting.
CONNECT The modem says, “Send me the ADPCM data.”
<Data> The DTE sends a previously recorded message from a very fast talking person: “Hello,
this is Dave. Press * to send a fax, # for help, or leave your message at the beep.”
Note that the caller can enter DTMF tones at any time, which the DTE can take into
account, or calling tone can still be detected.
<DLE><ETX> This ends the greeting message.
VCON The modem switches back to Online Voice Command Mode.
#VTS=# The DTE sends # as the beep.
VCON The modem is still able to receive DTMF or Calling tone here.
#VRX Enter Receive Mode. Now the modem is clocking silence, as well as DTMF, and
recording whatever the caller says.
<DLE>s #VSP must have been set to 35, since 3.5 seconds later the modem sends this
indication of silence period expiration. No ADPCM data was sent to the DTE, because
the data pump deleted all 3.5 seconds of silence. This tells the DTE that nobody is
talking.
! The DTE issues a key abort to switch to Online Voice Command Mode.
<DLE><ETX>
VCON The modem exits Voice Receive Mode and switches to Online Voice Command Mode.
#CLS=0 The DTE received no voice data, just the silence indicator after a 3.5 second wait.
Since there was no calling tone and the user never entered any DTMF tones, the DTE
assumes it must be a calling data modem. If the data handshake fails, the modem
does not hang up the line thus giving the DTE another chance to try the fax again (in
this case).
OK The modem is now a data modem.
A The modem pretends that it just got RING, try V.22 bis/V.42 bis, etc.