Rockwell RCV144ACx, Справочник по командам

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AT Command Reference Manual
7-40 1048
Table 7-11. Answer Call, Determine It's a Fax
DTE to Modem Modem to DTE Description and Interpretation
RING Sometime later, the next beta-site calls.
#CLS=8 Configure the modem for Voice Mode.
OK The modem agrees, and is now set up for voice.
#VBS=4 The DTE asks for 4-bit compression (ADPCM). The DTE needs to work at 38,400 bps
since after start and stop bits are added the speed increases to 36,000 bps.
OK The modem is configured for 4-bit compression.
#BDR=16 The DTE knows that 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. All
subsequent commands are assumed to be sent at 38,400 bps. The S30 timer is now
active.
#VSS =2 Sets silence detection sensitivity to midrange.
OK The modem confirms command reception.
A Finally, the modem answers.
VCON The modem is now in Online Voice Command Mode. DTMF and calling tone detection
is enabled. (Note that alternatively, the DTE can go into the Transmit or Receive mode
and look for either calling tone or silence as a means of discrimination.) The DTE waits
a few seconds to give a possible fax machine or remote data/fax modem a chance to
send calling tone without being disturbed by a voice greeting. (In this example only
calling tone is considered, which excludes a person sending a fax when he hears
answer tone.)
<DLE>c The modem has detected T.30 Calling tone and presents this information to the DTE.
#CLS=1 The DTE decides to receive the fax, and tells the modem to pretend that it just went
off-hook as a Class 1 Facsimile modem. The DTE must be able to handle Class 1
commands from here on. Note
OK The modem is now a Class 1 fax modem.
A The modem pretends that it just got the incoming RING, and modem handles the fact
that it is already off-hook.