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Leased Line Operations
A leased line, or private line, is a telephone line that permanently connects two or more
locations. The leased line does not have any switching equipment associated with it.
Leased-line operation with the modem is selected with the &L command.
The &L command informs your modem that communications will occur over leased lines, with
no answer tones being generated by the modem. If the modem detects a loss of the remote carrier
signal while leased-line operation is selected, it will attempt to re-establish the connection rather
than hang up.
If you select leased line operation with the &L1 command, you must issue the ATA command to
answer a call, and the ATD command to initiate a call. If you use &L2 or &L3 to select Auto
leased line operation, you do not need to issue the ATA or ATD commands; &L2 selects
Originate mode automatically and &L3 selects Answer mode automatically. To dial or answer,
raise DTR; to return to local command state, lower DTR.
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You will require a special phone cable (available from your dealer) to connect
your modem to a leased-line socket. The phone cable supplied with your modem
is suitable for use with normal, dial-up, voice (PSTN) lines.
Before commencing leased-line communications, it is recommended that a non-auto-ranging B
setting be specified.
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If error correction is required, select a Reliable mode, not an Auto- Reliable
mode. (See the \N command.)
Auto-ranging and fallback are disabled in leased-line mode. Your modem will only attempt to
connect using the communications standard specified by the B command and the terminal speed.
Once a connection has been established, if your modem detects a loss of carrier it will
continuously attempt to re-establish the connection.
Smart Leased- Line Mode
Leased-line operation is available in both asynchronous and synchronous modeÊ 1.
Calling and AnsweringUsing &L1
When operating in smart mode (&L1 set), the ATD and ATA commands are used to initiate and
answer calls respectively.