Appendix I; Testing Your Mmh2834; Introduction - Multitech MMH900 User Manual

Appendix I

Testing Your MMH2834

I.1 Introduction
Each time power is applied to a MultiMux with an internal MMH2834
modem, the MMH2834 performs an automatic self- test to ensure proper
operation. The MMH2834 also has three diagnostic test features: Local
Analog Loopback, Digital Loopback (remote/automatic) and Digital
Loopback (local/manual). These diagnostic tests can be run after the
modem is selected using the #CLA1 command.
A loopback test involves entering data from your PC and looping that
data through the circuits of your modem and/or a remote modem. When
the loop has been completed, the original data entered should match the
data received back on your PCs monitor after the test.
The Local Analog Loopback Test allows you to verify that the modem's
transmitter and receiver circuits are functioning properly.
The Digital Loopback Test (local/manual) allows you to verify that the
remote computer or terminal, the remote modem, serial ports, the
telephone line and the local modem are functioning properly.
The Digital Loopback Test (remote/automatic) allows you to verify that
the local computer or terminal, the two modems and the transmission
line between them are functioning properly.
In asynchronous mode, upon completion of testing, enter either Escape
Sequence, +++AT<CR> or <BREAK>AT<CR>.
Note: All loopback tests will operate at all speeds except 300 bps.
Appendix I - Testing Your MMH 2834
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