Nortel Passport 7400, Hardware Installation, Maintenance, And Troubleshooting, Page: 182 / 438

182 Chapter 37 Hardware procedures
241-7401-240 5.2S1
Configuring the modem software
Configure the modem software after you set the modem dip switches.
Prerequisites
Ensure you have a computer or terminal with an RS-232 port that you can
temporarily connect to the modem while you adjust the modem settings. The
RS-232 port must be capable of running at 9600 BPS; otherwise, the modem
will not be able to communicate with the Passport switch local operator port.
Procedure steps
1 On the modem, set dip switch 8 for the smart mode to on (down).
2 Switch the modem power off, then on again.
3 Set the computer or terminal to use software flow control, also referred to
as the data leads only mode. Otherwise the modem may not be able to
communicate with the computer or terminal.
4 Connect the modem to the RS-232 port of a computer or terminal using a
standard straight-through serial cable. Typically, the cable has a 9-pin
D-sub female connector at one end and a 25-pin D-sub male connector
at the other end.
Note: Do not use the V.24 DCE cable (PEC NTBP25) provided with the
Passport switch. Also, do not use the cable you want to use to connect the
modem to the CP.
5 Enter the following commands:
• ATQ0 (with a zero, displays result codes so that the modem responds
with OK after this command and whenever an attention command
(AT) is entered).
• ATZ4 (loads a generic hardware flow control configuration when the
cable from “Modem cable specifications” (page 141) is to be used.
Otherwise enter ATZ5. Some functionality will be disabled)
• ATQ0 (with a zero, displays result codes and OK)
• AT&M0 (optional command) (with a zero, disables error control; use
only if the dialing modem does not support error control)
• AT&W0 (with a zero, writes the current configuration to non-volatile
memory, NVRAM 0)
• ATY0 (with a zero, uses NVRAM 0 as the default configuration)
6 Disconnect the modem from the computer or terminal.