Rockwell Automation 57C409 2 Channel Analog Input Module - Manual (Page 29)

5Ć3
5.3 Interrupt Problems
Problem: No interrupts at all, or too many (unexpected) interrupts,
signified by error codes being displayed on the faceplate of the
Processor module. Go through the following steps first before going
on to the more specific troubleshooting steps:
Step 1.
Verify that the input module is in the correct slot and that
the I/O definitions are correct.
Refer to figure 3.2. Verify that the slot number being
referencedagrees with the slot number definedin the
configuration.
Verify that the configuration task contains the proper
interrupt control definitions.
Step 2. Verify that the user application program is correct.
Verify that the application program that uses the symbolic
names assignedto the module in the configuration task
has defined those names as COMMON.
Compare your interrupt task with the examples given in
sections 4.4.1 and4.4.2. Make sure that the actions shown
in the examples are performedin the same order in your
program.
5.3.1 No Interrupts
Problem: The program does not execute but no error codes are
displayed on the Processor module faceplate. If interrupts are never
receivedby the application program andthe watchdog timeout
parameter in the event definition was disabled, the program will never
execute.
The watchdog timer for this module must never be disabled. Before
you can determine why the program did not execute, you must first
set the timeout parameter in the event definition. Run the program
again andproceedto section 5.3.2.
5.3.2 Hardware Event TimeĆOut
Problem: All tasks in the chassis are stoppedanderror code 12"
appears on the faceplate of the processor module. The interrupt has
either never occurred, or is occurring at a slower frequency than the
value specifiedin the timeout" parameter in the event definition. Use
the following procedure to isolate the problem:
Step 1.
Verify that the timeout value is set correctly.
Check the value specifiedin the timeout" parameter in
the event definition. The unit is in ticks. Each tick is equal
to 5.5 msec. The timeout value shouldbe at least 2 ticks
greater than the interrupt frequency. It can reasonably
range up to 1.5 times the interrupt frequency.
Step 2. Verify that the user application program is correct.
Review the examples in section 4.4. Make certain that
common clock has been enabled.