Installation guide

Chapter 6: Modem Guide

6-10 CSMIM-T1 Hardware Installation Guide

Bell 103 Protocol

Bell 103 protocol is for 300 bps full-duplex connections. The features

described in this guide apply to Bell 103 operation except that your

modem does not support:

• Digital (loop 1A) and analog (V.54 loop 3) loopback.

• LAPM connections.

6.4.1 Protocol Conﬁguration Command Settings

When you send an AT string to the modem, it adjusts modem-port speed

automatically to match the AT speed. Use %G1 to disable this feature.

With %G1 set, you can change the modem speed with %Bn (where n is

the new modem speed) and %Fn.

This section lists settings to conﬁgure the modem for each mode and

protocol. Modem connection speeds are in parentheses.

Table 6-3 Conﬁguring the Modem with %F0 Set

NOTE

When your modem establishes a reliable Bell 103 connection,

it displays CONNECT 103/REL - MNP. For a normal or direct

Bell 103 connection, the message is CONNECT.

Protocol Issue %G0: Issue %G1:

V.21 (75-300 bps) B0 at 300 bps B0%B300

Bell 103 (75-300 bps) B1 at 300 bps B1%B300

V.22 (600 bps) at 600 bps %B600

V.22 (1200 bps) B0 at 1200 bps B0%B1200

Bell 212A (1200 bps) B1 at 1200 bps B1%B1200

V.34/V.22bis (2400 bps) at 2400 bps %B2400

V.34/V.32bis/V.32 (4800 bps) at 4800 bps %B4800

V.34/V.32bis (7200 bps) at 7200 bps %B7200

V.34/V.32bis/V.32 (9600 bps) at 9600 bps %B9600

V.34/V.32bis (12000 bps) at 12000 bps %B12000