How do I select the leased line mode, a switch or an AT command? How do I select the answer and originate modem?

Leased line mode is controlled with the&L command.

Command: ----------&Ln ---------- Leased Line Operation
Values: --------------------------------- n = 0, 1, or 2
Defaults: ------------------------------ 0

Description:

&L0 The modem is set for standard dial-up operation.
&L1 The modem is set for leased line operation in originate mode.
&L2 The modem is set for leased line operation in answer mode.

Note: For&L1 and&L2, there is a 30-second window between power up and the starting of the leased line handshake. During this time, you can turn off the command, if desired.