Rockwell Automation 57C421B Pulsetach Input Module/DCS 5000/AutoMax User Manual

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5Ć8

Step 2.

Verify that the hardware is working correctly.

WARNING

INSERTING OR REMOVING A MODULE OR ITS CONNECTING CABLES MAY

RESULT IN UNEXPECTED MACHINE MOTION. TURN OFF POWER TO THE RACK

BEFORE INSERTING OR REMOVING A MODULE OR ITS CONNECTING CABLES.

FAILURE TO OBSERVE THESE PRECAUTIONS COULD RESULT IN BODILY INJURY.

The problem may be in one of three areas. Replace these

items one at a time and determine whether the problem

has been corrected before attempting to replace the next

item. First replace the Pulsetach Input module, then the

Processor module(s), and finally the backplane.

Step 3.

If you are using the comparator equal function, you must

set the comparator value before you enable the

comparator equal interrupt (bit 11 of register 5).
The TIMEOUT parameter in the EVENT statement should

be disabled if interrupts are not timeĆbased. See section

4.4.3 for an example.
At power up, all internal registers are reset to zero. If you

do not set the comparator value before you enable the

interrupt at power up, when all internal registers are equal

to zero, a comparator equal interrupt will be issued (error

code 1b").

5.3.4

Illegal Interrupt Detected

This condition results in error code 1F" appearing on the faceplate

of the Processor module. It means that a hardware interrupt has

occurred and no event has been defined using the (BASIC) EVENT

statement. When this error occurs, all tasks in the rack will be

stopped:
Step 1.

Verify that the application task is correct.
Verify that your interrupt response task contains an

EVENT" statement that will be executed. Check carefully

to determine whether a higher priority task is preventing

the interrupt response task from running.