Remote Digital Loopback Test (V.54 Loop 2) - Multitech MULTI MODEM II MT5600BL User Manual

MultiModemII User Guide
2. Type AT and press E
3. Type AT&T1 and press E
4. Note that the CD and TM indicators are on. If they are not on, there is a defect in
5. Enter characters from your keyboard. For this test, typing multiple uppercase U
6. To exit the test, type the escape sequence +++AT and press E
7. Your modem passes this test if the data received on your monitor are the same
Note: You can also start and stop an analog loopback test by using the front panel
LCD and buttons. See "Diagnostic Options Trunk" in Chapter 3.

Remote Digital Loopback Test (V.54 Loop 2)

The remote digital loopback test tests the phone lines and the circuits of both your
modem and a remote modem. In this test, your modem must be on line with another
modem that is set up to respond to a request for remote digital loopback. (Note that
some modems might not support remote digital loopback or might have it disabled.)
Data from your computer or terminal is transmitted through your modem and over
the phone line to the remote modem, where it is then looped back to your modem.
Figure C-2. Remote digital loopback test.
Test procedure
1. Arrange to have &T4 set on the remote test modem. This command enables the
NTER
press E to disable error correction.
NTER
mode in the originate mode. A CONNECT message should appear on your dis-
play. The modem is now out of command mode and in a pseudo-online mode.
your modem.
characters is a good way to send an alternating test pattern of binary ones and
zeros. The characters entered should be displayed on your monitor.
modem in online command mode. Then type either AT&T or ATH to return to
command mode.
as the data entered from your keyboard. If different data appear on your moni-
tor, your modem is probably causing the problem, though it could also be your
computer. If your modem passes this test, but you are receiving errors while on
line, the remote modem or the phone line could be at fault.
remote modem to respond to an &T6 request for a remote digital loopback test
from the local modem.
; you should get an OK message. Type AT\N and
. This places your modem in analog loopback
NTER
C Loopback Tests
. This puts the
NTER
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