Verilink Productivity 500 (34-00236) Product Manual - Manual (Page 75)

Test Mode Operation 500 TA Page 75
Chapter 14 Test Mode Operation
COMMUNICATION DIAGNOSTICS
Communication diagnostic tests verify that the 500 TA, the PC, the central
office switch, and the remote unit are operating correctly. These tests can help
determine the source of a fault down to a particular element responsible for it.
Communications tests are initiated and terminated via the AT command set.
NOTE: If the S18 Test Timer is enabled (not set to 0) then any test currently
executing will end when this timer expires.
Local Terminal Loopback &T9 S18
A local terminal (DTE) loopback loops data back to the PC by connecting the
TD and RD pins so that whatever the PC sends is echoed back (
Figure 6 ).
Figure 6 Local Terminal Loopback
To initiate the test, enter AT&T9 from the PC. The 500 TA may be online or
offline when the test is initiated. Any protocol, mode, and DTE rate can be
used. The test is successful if the data is successfully echoed back to the PC. A
BERT device can be helpful in checking for data errors. This test verifies the
operation of the PC, the PC cable, and the PC interface of the 500 TA.
This test terminates when the S18 timer expires.
DTE
ISDN
Interface
DTE
Interface
ISDN
Line
ISDN
Receiver
ISDN
Transmitter
Protocol