Nortel Passport 7400, Установка оборудования, техническое обслуживание и устранение неисправностей, Страница: 141 / 438

Chapter 28 Modem installation 141
Passport 7400 Hardware Installation, Maintenance, and Upgrade 5.2S1
Modem installation supporting information
Modem selection
You do not need to configure any Passport software in order to connect a
modem to the CP. However, you must be able to configure the modem and
assemble the cable in accordance with the information contained in the
following sections:
• “Setting modem dip switches” (page 407)
• “Modem cable specifications” (page 141)
• “Configuring the modem software” (page 182)
The modem used as an example hookup is a 56K modem manufactured by
US Robotics, which includes their older Sportster series modems. Choose a
modem that supports the same dip switch settings and AT software
commands. The modem must also support the dumb mode so that the
Passport will not reconfigure the modem while it is on-hook.
Modem cable specifications
You cannot use the DCE V.24 cable assembly with product engineering code
NTBP25 to connect a modem to port 1 of the CP in a Passport. The connector
on the faceplate requires a customized DB-9 cable.
You need the following components in order to assemble the cable:
• a V.24 serial interface cable
• a male 25-pin D-sub connector to connect to the modem
• a male 9-pin D-sub connector to connect to port 1 on the faceplate of the
CP in the Passport
If your switch is in a cabinet, determine the length of cable required by
measuring the distance from the faceplate of either CP through the cable
management guide to the rear of the shelf. You can install the modem inside
the cabinet and, optionally, fasten it to the cable management guides.
The cable and its connectors must be custom-made according to the table
“Pinout for the Passport DB 9-pin connecting to the modem DB 25-pin”
(page 142).