Patton electronics 1092RC, User Manual

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Switch S1-3: Data Set Ready During Local Line Loopback Test
Use Switch S1-3 to control the behavior of the DSR signal at the
EIA interface during the local line loopback test.
S1-3 Setting Description
On Enabled DSR is on during local
line loop (default)
Off Disabled DSR is off during local
line loop
Switches S1-4 and S1-5: Async/Sync Operation
Use Switches S1-4 and S1-5 to configure the Model 1092 for
async/sync operation. Both switches must be set in the “Off” position.
There is no other valid setting.
S1-4 S1-5 Setting
Off Off Allows sync/async control
On Off Reserved
Off On Reserved
On On Reserved
Switches S1-6 and S1-7: Transmit Clock Source
Use Switches S1-6 and S1-7 to configure the 1092 for internal,
external, or receive recover clock mode.
S1-6 S1-7 Setting Description
On On Internal Transmit Clock
derived internally
Off On External Transmit Clock
derived from the
terminal interface
On Off Receive Recover Transmit clock derived
from the received line
signal
Off Off hardware reset
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Important:
A pair of Model 1092s communicate synchronously
across the twisted pair line connection. Therefore, you must set
these switches whether your application is async or sync .
For X.21 or Async applications, please configure one Model 1092
for internal clock mode and the other Model 1092 for receive
recover clock mode.
ER glows red to indicate the likelihood of a Bit Error
in the received signal. During the 511 or 511/E
test, ER flashes to indicate that the Test Pattern
Detector has detected a bit error.
TM glows red to indicate that the Model 1092RC
has been placed in Test Mode. The unit can be
placed in test mode by the local user or by the
remote user.
NS (No Signal) glows red to indicate that the local
Model 1092RC has not yet connected with the
remote Model 1092RC.
5.2 TEST MODES
The Model 1092RC offers two proprietary loopback test modes,
plus a built-in V.52 BER test pattern generator, to evaluate the condition
of the modems and the communication link. These tests can be
activated physically from the front panel, or via the interface.
5.2.1 Using Local Line Loopback (LLB)
The Local Line Loopback (LLB) test checks the operation of the
local Model 1092RC, and is performed separately on each unit. Any
data sent to the local Model 1092RC in this test mode will be echoed
(returned) back to the user device (see Figure 11, below). For
example, characters typed on the keyboard of a terminal will appear on
the terminal screen.
To perform an LLB test, follow these steps:
1. Activate LLB. This may be done in one of two ways: First, by
moving the front panel toggle switch to the right to “Local”.
Second, by raising the LLB signal on the interface (see
Appendix C). Once LLB is activated, the Model 1092RC
transmitter output is connected to its own receiver. The “TM”
LED should be lit.
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1090
Figure 11 Local Line Loopback
1092RC