Dataplex DPX-213, User Manual

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Section 4
AT COMMAND SET
Copyright (C) Dataplex Pty Ltd
4-5
3. Data State
After an ATA (Answer) or ATO (Originate) command, the modem enters the Data
State. The modem will attempt to handshake with the remote modem or if already
connected will enter begin to exchange data.
The normal Data State is transparent and all characters issued by the DTE are
passed to the remote end. Sometimes you may need to abort the operation and
regain control of the local modem instead of the remote DTE. This is possible in the
On-line Command State and is selected with the escape sequence.
Several other interface or line events that will cause the modem to drop out of
transparent data transmission (Data State) to local control (On-line Command State)
are described as follows:
1. Escape Sequence Detected ('pause'
+++
'pause')
The modem will leave the data state and execute the following sequence: send
an "OK" message to the DTE, clamp transmit data to mark, disable receive data
to DTE and enter the On-line Command State.
2. Loss of Carrier Detected (provided S10 is not set to 255)
The modem will execute the following sequence: send a "NO CARRIER"
message to the DTE, go on-hook and returns to Idle State.
3. DTR Dropped (provided DTR is not forced on and AT&Dn is set)
The modem will execute the following sequence: send a "NO CARRIER"
message to the DTE, go on-hook and return to Idle State.
4. DTR Dropped (provided DTR is not forced on and AT&D2 or AT&D3 is set)
The modem will execute the following sequence: send a 'NO CARRIER'
message to the DTE, go on-hook and return to Idle State.