Case Communications syncro 1496, Reference Manual

Page: 90 / 192

7.3 Testing via the Front Panel
You can use the buttons on the front panel of the modem to perform
loopback tests, using either the self-test feature, or an external terminal or
test set.
7.3.1 Local Analogue Loopback
Using the Modem's Test Pattern Generator (Self-Test)
1. Press the
TEST
button, then the
AL
button. The
RUN
indicator should
flash to show that a test is in progress.
2. The
DSR
indicator will flash each time a test pattern mismatch occurs.
3. To terminate the test, release the
TEST
and
AL
buttons in any order. The
total number of errors will be displayed on your terminal. If your
modem is operating correctly you will get the response
000 ERRORS .
4. You may inject errors (to check that the test pattern is working
correctly) if an appropriate
/T
option is set, by using the
ENTER
button.
Using an External Test Source
1. Press the
AL
button.
2. The
DCD
indicator should light and the
RUN
indicator flash. If the
DSR
indicator lights, there is a fault on the modem.
3. Attach a terminal or test set (set to synchronous mode), running from
the modem's clock, to the DTE port of your modem.
4. Transmit a test pattern. If the pattern is echoed back, the analogue loop
is working correctly. If the pattern is not echoed, or is corrupted, check
the LEDs:
– If only the
TXD
light flashes when the pattern is sent from the
terminal, check the terminal settings and DTE cable. If these are
correct, the modem is faulty.
– If both the
TXD
and
RXD
lights flash when a pattern is sent from the
terminal, and no pattern or only a corrupted pattern is echoed back,
check the terminal settings and the DTE cable. If these are correct,
the modem is faulty or strapped incorrectly.
X450-310851 Issue 2 7-4 Rev.0