Telenetics 56 manual Auto Leased Line Operation &L2 or &L3

☞Your modem will hang up and return to local command state if your computer transmits characters while the modem is attempting to establish or re-establish a connection (unless &N0 has been issued).

Auto Leased Line Operation (&L2 or &L3)

You can select Auto leased line operation with the &L2 or &L3 command. In Auto leased line operation you do not need to issue the ATA command to answer a call, or the ATD command to initiate a call. Issue the &L2 command to automatically select Originate mode, or the &L3 command to automatically select Answer mode.

In Auto leased line operation AT commands can only be entered while DTR is low. Irrespective of the &D setting, your modem will remain in idle mode when DTR is low, and will go on-line when DTR is high and the modem’s TALK/DATA switch is set to DATA. If DTR is lowered (or the TALK/

DATA switch is set to TALK) when your modem is on-line, it will hang up and return to idle mode. If power is lost, your modem will enter on-line state when DTR is restored.

☞Your communications software must be capable of altering the state of the DTR signal to work successfully with the &L2 and &L3 commands.

If your modem has a TALK/DATA switch, it must be set to DATA.

Hanging Up

There are four ways of hanging up your modem when leased-line mode is selected.

❏If your modem is attempting to establish or re-establish a connection, sending characters to it will cause it to hang up (unless &N0 has been issued).

❏If synchronous mode is selected, lowering the DTR signal will cause your modem to immediately hang up.

❏If asynchronous mode is selected, issuing the ATH command will cause the modem to hang up.

❏If asynchronous mode is selected (&L2 or &L3), lowering DTR will cause the modem to hang up.

❏Switch the TALK/DATA switch to TALK.

☞XON/XOFF flow control should not be selected for leased-line connections. Your modem will prematurely hang up if your computer sends an XON/XOFF character while the modem is attempting to reestablish a connection.

Improving the Reliability of Leased-Line Connections If you are experiencing data errors over leased lines, issue the %L command to lower the transmit level of your modem. You may need to experiment with the levels, but start between %L15 and %L19.

The transmit level should be changed on both modems.

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