General DataComm 060A027-001, Installation & Operation Manual

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V.25 bis Command Set Operation ITU-T V.25 bis Command Procedures
5-10 SpectraComm Dual V.34 Modem 060R122-000
Installation and Operation Issue 15
• A long space is received and long space disconnect has been enabled by the Yn AT command.
This mode of automatic termination functions only when the modem is operating at 300, 1200,
or 2400 bps.
108.2 Call Establishment Procedure
The general principle for establishing a call between the DTE and DCE complies with the V.25 bis
108.2 mode of operation and is outlined below:
Originating a Call
Answering a Call
DTE DCE
Turn On DTR. Turn On CTS.
Send Command: CRN or CRS. Send VAL response.
Dial phone number.
Wait for the connection (or abort the call by turning Off DTR). Turn Off CTS when answer tone is detected or
send CFI response in cases where the call has
failed.
Turn On DSR and DCD when handshake is
successful.
Recognize successful connection when DSR comes On.
Recognize connected data rate from the CNX message. Send connect CNX message.
Enter data transfer mode.
Turn On RTS to send data. Turn On CTS in response to RTS.
Turn Off DTR to terminate call. Disconnect from line.
Turn Off CTS, DSR, and DCD.
Send CFI call abort message.
DTE DCE
Turn On DTR. After detection of an incoming ring, send INC
message.
When Auto Answer is enabled, modem will
answer call after preset number of rings if DTR is
On.
The CIC command is not required.
Send CIC command to permit answering, or send DIC
command to disregard the incoming ring. Disregard incoming ring if DIC is received.
Answer call after the next ring if CIC is received.
At next ring, go off-hook.
Turn Off CTS.
Turn On DSR and DCD when going through
handshake successfully.
Recognize successful connection when DSR comes On. Send connect CNX message.
Go into data transfer mode.
Recognize connected data rate from the CNX message.
Turn On RTS to send data. Turn On CTS in response to RTS.
Turn Off DTR to terminate call. Disconnect from line.
Turn Off CTS, DSR, and DCD.
Send CFI call abort message