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CHAPTER 5: Troubleshooting
5.1 Self-Tests
The Code Operated Matrix Switch has a number of
self-tests to ensure that its circuitry is fully
operational. These tests check the RAM, LEDs, DIP
Switches, and Serial Ports. An Interrupt Test can
also be performed.
• The RAM Test checks the internal memory of
the Switch by writing an internal test pattern,
and then reads it for accuracy. This test checks
the integrity of the RAM.
• The LED Test checks the LEDs by turning them
all OFF, then ON one at a time, then all ON,
then OFF one at a time. This test tells you
whether the LEDs are working normally or
whether any are shorted. The test runs
continuously until you press any key to exit.
• The DIP Switch Test reads the DIP switches and
displays their settings on the screen. This test
tells you whether the DIP switches and
associated circuitry are operating normally and
are set up the way you want them. The settings
will be displayed on the screen continuously un-
til you press any key. Then the test checks
whether an Expansion Board is installed. (If an
Expansion Board is not installed, readings will
be displayed but can be disregarded.)
• The Serial Port Test is a simple loopback test
that checks whether data is being correctly
transmitted and received on any particular port.
This test also checks, using DTR/CTS/RI or
RTS/DCD, whether the box can loop control
leads back properly.
• The Interrupt Test checks the interrupt circuitry
of the Switch. During this test, the letter
A
will
appear on the screen. A message will indicate
whether the test passed or failed.
NOTE: To perform a data test, jumper Pins 2 and 3
together on the port you want to test. To test
DTR/CTS/RI, jumper Pins 20, 5, and 22
together. To test RTS/DCD, jumper Pins 4
and 8 together.
To run a self-test, follow these steps:
1. Using the shunt, configure Port 0 as DCE.
2. Set the terminal to 9600 baud, 1 stop bit, no
parity.
3. Connect the terminal to Port 0, using only Pins
2, 3, and 7.
4. Set DIP Switch 3 on Switch F to the ON position
(the switch is OFF for normal operation).
5. Power the switch on.
6. When a self-test is run, this message will appear:
Type in your reply: capital
R
or capital
O
.
If you select
R
, the tests you select from the next
menu will repeat until you press the BREAK key.
O
will run tests only once.
After you’ve picked
R
or
O
, this menu appears:
If you select
A
, you get the following tests:
5. Troubleshooting
**CODE OPERATED MATRIX SWITCH SELF TEST V 1.0**
RUN TESTS (R)EPEATEDLY OR (O)NCE?
WHICH TESTS SHOULD BE RUN?
(R)AM TEST
(L)ED TEST
(D)IP SWITCH TEST
(S)ERIAL PORT TEST
(I)NTERRUPT TEST
(A)LL TESTS
