Motorola DDS/MR64, Installation And Operation Manual

Page: 45 / 69

DDS/MR64 5-1
Chapter 5
Diagnostics
TEST FEATURES
By selecting various tests available through the front panel options, you
can send test signals or patterns to check the operation of components in
the network. During any test, TM is on constant for locally initiated tests
and blinks for remotely initiated tests.
☞
Note
To attempt to clear TEST PATTERN ERRORS message from
the LCD, press YES or NO. If the error message is not
replaced with TEST PATTERN OK, then errors are still
being received.
To stop the test, press HOME, then respond to the question
EXIT TEST? by pressing YES.
Remote Terminal Loopback RT
This test causes the local DDS/MR64 to loop back a remotely generated
test signal to check the remote unit (Figure 5-1). If the signal returns
unchanged, the remote unit and the DDS network are OK.
A bilateral loopback test lets the local DTE loop a signal through the
DTE interface. This tests the DTE transmit and receive circuits.
Local Line Loopback LL
This test checks the transmit and receive logic components in one loop
circuit and the transmit and receive line components in another loop
circuit (Figure 5-2). The DDS/MR64 loops a signal from the DTE
through the logic components and back to the DTE. If the signal does
not change, the logic components are OK.
At the same time, the DDS/MR64 loops a signal through the transmit
and receive line components. If the signal does not change, the line
components are OK.