DTE to Modem
Modem to DTE Description and Interpretation
RING Sometime later, the next site calls.
#CLS=8 Configure the modem for Voice Mode.
OK The modem agrees, and is now set up for voice.
#VBS=3 The DTE asks for 3-bit compression. The DTE needs to
work at 38,400 bits/s since after start and stop bits
are added, the speed increases to 27,000 bits/s.
OK The modem is configured for 3-bit compression.
#BDR=16 The DTE knows that compression requires a 38,400
bits/s speed, so it forces this as the new speed.
OK This OK message is sent at 9600 bits/s, but the modem
then switches to 38,400 bits/s. All subsequent
commands are assumed to be sent at 38,400 bits/s. The
S30 timer is now active.
#VSS=2 Set sensitivity to normal setting.
OK The modem confirms command reception.
#VSD=1 This enables silence deletion.
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. (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
an answer tone is heard.)
<DLE>c The modem has detected T.30 Calling tone and presents
this information to the DTE.
#CLS=1 The DTE decides to receive a 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 this point on.
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.
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