B1/B2 Loopback With Self-Test (At&T11); The Diagnostic Command (Atcg) - ZyXEL Communications ACCESSING INTERNET & INTRANET omni series User Manual

character through the DTE interface to the ISDN TA will
discontinue the test.
B1/B2 Loopback with Self-test (AT&T11)
There is an AT command designed for testing the readiness of your
ISDN line which uses one B-channel (B1) to place a call and the
other B-channel (B2) to receive the call.
Follow these instructions to make your test call:
Type:
AT&ZOI=your_isdn_number<Enter>
TA responds:
OK
Type:
AT&T11<Enter>
TA responds:
OK
Dial your_isdn_number
Loop from B1 to B2 through the switch established!
Sending and receiving data.....
B1/B2 loopback test successed.
Disconnecting.....
NO CARRIER

The Diagnostic Command (ATCG)

The ATCG command can be used to test and isolate hardware
problems. Some of the tests are interactive operations, just follow the
indications prompted on the screen. If the TA is operating normally,
the test results will be displayed as follows:
System address & data bus test .......................
Layer 1 hardware test ...............................
Layer 2 hardware test ...............................
Layer 1 activation test..............................
First B channel hardware test .......................
Second B channel hardware test.......................
Listen to the Ring and then pick up phone set #1.....
Off-hook action is detected, (Hook Interrupt) .......
Listen to the dial tone and then dial 1234567890*# in sequence.
1234567890*#
102 Diagnostics
OK
OK
OK
OK
OK
OK
!!
OK
!!