ADTRAN DSU 56/64, Руководство пользователя

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Chapter 3. Test Modes
61200062L1-1 DSU 56/64 User Manual 3-3
To initiate the
DTE O
NLY
test, perform the following steps:
1. Press S
ELECT
once to turn on the DTE test indicator.
2. Press T
EST
while the test indicator is on.
3. To terminate the test, press T
EST
.
Test data from the terminal or test equipment is routed through the
DTE section of the DSU 56/64 and then to the output of the loop
transmitter section where the signal is encoded for transmission.
The output of the loop transmitter is coupled back to the loop
receiver input. The received test signal is then decoded and
returned to the terminal or test equipment where it is checked for
any bit errors.
DTE WITH TEST PATTERN (TP)
The DTE
WITH
TP test is similar to the DTE O
NLY
T
EST
described in
Figure 3-1 on page 3-2. It is initiated at the local DSU 56/64 and is
used to independently test the operation of the DSU 56/64.
To initiate the DTE
WITH
TP test, perform the following steps:
1. Press S
ELECT
twice to turn on both the DTE and PTRN test
indicators.
2. Press T
EST
while these test indicators are on.
3. To terminate this test, press T
EST
.
Instead of using data from the terminal or test equipment, this test
utilizes an internal test pattern generator and detector in the DSU
56/64. The loopback point and the data paths for this test are
illustrated in Figure 3-2 on page 3-4.