Remote Digital Loopback Test (V.54 Loop 2) - Multitech MultiModem DSVD MT5600DSVD User Manual

MultiModemDSVD User Guide
3. Type AT&T1 and press E
4. Note that the CD LED is on. If you are set for 14,400 bps or higher, a speed LED
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 characters received on your monitor are the

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
2. Open your communications software and go into terminal mode. Type AT and
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.
should be on. If the CD LED is not on, there is a defect in 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.
same as those entered from your keyboard. If different characters appear on
your monitor, your modem is probably causing the problem, though it could
also be your computer. If your modem passes this test, but you are receiving er-
rors 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.
press E ; you should get an OK message. Type AT\N and press E
NTER
disable error correction. Type AT+MS=9,1,9600,9600 and press E
local modem to V.32 mode at 9600 bps.
. This places your modem in analog loopback
NTER
C Loopback Tests
. This puts the
NTER
to
NTER
to set the
NTER
65