Multi-Tech Systems BL-Series manual Digital Loopback Test Local/Manual Synchronous Mode

MultiModemBL User Guide

8.8Digital Loopback Test (Local/Manual) (Synchronous Mode)

This test must be run when you have a data connection with another modem. If a Local Analog Loopback Test resulted in errors, and this test passes without errors, then the problem exists in your computer-to-modem connection. In Digital Loopback Test (local/manual) mode, data passed from the remote modem’s transmit circuit are looped back from the local modem and are received at the remote modem’s receive circuit (multiple upper case “U” characters in Figure 8-6).

First make certain that you are set up for Synchronous operation by placing DIP-Switch #12 in the UP position. To initiate the Digital Loopback Test (local/manual), DIP-Switch #9 must be in the UP position, and the Answer/Originate switch (front of the modem) must be toggled to the UP position.

Once you receive an OK message from your modem (if responses are enabled), the local modem is placed in Digital Loopback mode.

To exit the Digital Loopback Test (local/manual), toggle the Answ/Orig switch to the Answer position.

UUUUU

UUUUU

Digital Analog Analog Digital

Computer or Terminal Local MultiModem	Remote MultiModem Computer or Terminal
DIP-Switch #9
UP; Answ/Orig
Switch Toggled to
Answ position
when On-line

Figure 8-6. Synchronous Mode Digital Loopback Test (local/manual)

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