DataComm V.34 PL, Operation Manual

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Tests Analog Loopback with Self-Test
060R115-000 DataComm V.34 PL Modem 4-3
Issue 1 Installation and Operation
Analog Loopback with Self-Test
Analog Loopback may be combined with Self-Test, as illustrated below. Upon initiation of Self-
Test, a pattern is generated by the transmitter and sent to the receiver for analysis. The pattern is
made up of alternate ones and zeros for 2400 bps. For all other speeds the modem generates a 511
test pattern. The number of errors is displayed on the screen. This test provides a means for you to
determine whether the problem is in the local data set.
Table 4-2 Analog Loopback with Self-Test
Step Front Panel
1. To start the test press AL, then press ST.
2. The modem flashes the TM LED and displays
the test names (LL and ST) while it is setting
up the test, then lights the TM LED and
displays four digits of the error count (0000 to
9999) while the test is running. It indicates
larger numbers by lighting decimal point one
and displaying the four least significant digits of
the actual count (for example, the actual error
count is 12345, but the modem displays
2.345).
3. To end the test, press AL, RDL or DL.
Modem transmitter
Modem receiver
Send data
Received data
DTE
Communications line
Local loopback
Self-test pattern
generator
Self-test pattern
receiver
V.34 PL
TR SD RD MR RS CS CO GD TM ALM OH
AL ST RDL DL SEL RST
ADV
1. To start the test press AL, then press ST.
2. TM flashes and the LCD displays the test names (LL and ST) while it is setting up the test,
then TM lights and the LCD displays four digits of the error count (0000 to 9999) while the test
is running.
3. When the timer (S-register 18) times out, the test ends.
4. To end the test, press AL, RDL or DL.