4-18
Diagnostics
GDC 048R154-000
test by means of either the terminal interface screen or the front panel
switches. Use of the terminal interface provides greater detail in the
test results. The test requires the cooperation of an operator at the
remote site to initiate the function in the remote DSU, observe the
results, and terminate the function.
In the DTE End-to-End Self Test, two DSUs transmit internally
generated test patterns to each other for verification. Bipolar violations
are corrected during this test. Within each DSU, a Test Pattern
Generator creates the test pattern, and a Test Pattern checker
determines if the data it receives matches that which was transmitted.
The test checks both DSUs and the T1 link.
To initiate the test from the terminal interface Diagnostics Selection
screen, select
[A] Start DTE Self Test
.
Figure 4-16 shows the switches and indicators that are involved when
you command a DTE End-to-End Self Test from the front panel.
Remember that when you initiate the test from the front panel the only
display of results is the TM indicator flashing in response to detected
errors. The terminal interface Diagnostics Results screen does not
display the results of tests initiated from the front panel.
Figure 4-15
Data Path for DTE End-to-End Self Test
Network
DeskTop T1 DSU
DTE
Interface
TPG – Test Pattern Generator
TPC – Test Pattern Checker
TPG
TPC
Network
Interface
TPC
TPG
DeskTop T1 DSU
DTE
Interface
Network
Interface
