DTE to Modem
Modem to DTE Description and Interpretation
#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.
#VSS=2 Set silence sensitivity. (It is assumed #VSD=1.)
OK The modem confirms command reception.
#VLS=0 This selects the telephone line, and ensures that it
is on-hook.
OK The modem confirms command reception, and is now set
up for voice.
#CLS=8 This ensure things are set up for voice.
OK The modem confirms command reception, and is now set
up for voice.
RING Sometime later, the next call is received. The modem
answers.
#BDR=16 The DTE knows that compression requires a 38,400
bits/s speed, so it forces this as the new speed. (For
example, the DTE was sending all commands, including
this one, at 9600 bits/s.)
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.
A The DTE answers.
VCON The modem is now in Online Voice Command Mode. DTMF
and calling tone detection is enabled.
#VTX 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.
CONNECT 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 ADPCM data
flow.
<Data> The DTE sends greeting message data. The modem waits
one second before starting to transmit to ensure
uninterrupted data flow. If the voice transmit buffer,
the transmission is disabled.
<DLE> The DTE has finished its transmission and now
<ETX> instructs the modem to enter Online Voice Command
Mode.
VCON 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, this response is delayed until the buffer is
empty.
#VBT=13 The DTE requests that DTMF digits be dialed as beep
having a duration of 1.3 seconds.
OK The modem agrees.
#VTS= [1000, The DTE sends a beep to annotate its greeting
0, 20], 9 message. This beep is a two second long 1000 Hz tone,
followed by a 1.3 second long DTMF 9. During this
period, the DTE is locked out.
OK After the modem sends the beep, it sends VCON to
inform the DTE that it is ready to move on. DTMF pass
through is re-enabled.
#VRX The DTE instructs the modem to turn the line around
and begin recording a message from the remote.
CONNECT The modem sets things up and enables ADPCM data
transfer to the DTE with the current silence deletion
setting.
<Data> 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.
<DLE>5 The caller has finished his voice message, but is now
insisting that he be able to send us a facsimile.
X DTE sends X as key abort. If the user talked after
DTMF 5 is pressed, anything said was lost. Whatever
was said before the 5 is on disk.
<DLE> The modem obeys key abort.
<ETX>
VCON
#CLS=2 The DTE instructs the modem to pretend no voice
activity has taken place, although the modem does not
hang up if the FAX fails.
OK The modem now thinks it is a Class 2 FAX modem. The
DTE can now tailor the +F settings which were not
accessible until +FCLASS became 2.
A Answer tone is generated and prompts the user on the
telephone to press the button on his FAX machine to
send his FAX. After the successful FAX is received,
the modem hangs up.
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