Total Control MP/16, Operator'S Manual

Page: 151 / 182

Modem Testing E-1
Appendix E Modem Testing
All loopback testing conforms to ITU-T Recommendation V.54.
Only one test can be performed at a given time. The LED for the
modem being tested will flash green while it is testing. If you send
a test command while the modem is in test mode, you will receive
an ERROR message.
Testing With &T
The tests supported through the &T command include analog
loopback, digital loopback and remote digital loopback. Users can
key in their own data during testing, or use the modem's internal
test pattern and error detector.
In all cases, disable error control before testing. If the modem is
detecting errors and retransmitting the affected data, your results
will be invalid.
Ending a Test
 
&T0, S18
Issuing the &T0 command terminates a test. Alternatively, set
Register S18 to a specified number of seconds, for example, S18=10.
When the 10 seconds are up, the modem automati cally ends the
test and returns to Command mode. If the test was Analog
Loopback, the &T0 command hangs up the modem. If the test was
Digital or Remote Digital Loopback, issue an ATH command to
hang up the modem, or an ATZ command to hang up the modem
and reset it to its defaults.
NOTE:
If you use the S18 test timer, but in the pro cess of testing
you issue an ATZ command, S18 resets to zero and the timer is
disabled. You cannot store a value for S18 in nonvolatile memory;
its power-on and reset default is always zero.