7.5
ChannelDeviceTesting
The first step in system testing is to check the operation of the multiplexer network section from each channel device to the MultiMux and back again to the channel device. These procedures will let you see if data from the channel device is passing through the MultiMux properly, by echoing channel keystrokes through the MultiMux and then displaying them as correct characters on the channel device’s monitor.
Table 7-3. Channel Device Testing Procedure
Step Procedure
1Place the local MultiMux unit in Test Mode 4 (i.e., executing the Local Loop test) by entering the following command. If using your external link device, this test does not apply.
AT&T4 (hit Return)
Note: The MultiMux must have downline loading turned off when doing channel device testing.
The supervisory console will display the following message:
LOCAL LOOP - TEST #4
2Enter data on the keyboard of each channel device and, if the local portion of your network is operating correctly, the data will be correctly displayed on each channel device monitor.
If the channel device is equipped with a local echo feature that is active,or if Echoplex is turned on for that channel, double characters will be displayed indicating that the MultiMux is correctly echoing data.
3When you have verified that the channel devices are operating correctly, enter the following to end the test:
ATZ(hit Return)
or
AT&TO (hit Return)