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Error reporting chapter 7 – Rockwell Automation 1775-KA PLC-3 Communication Adapter Module User Manual User Manual

Page 93

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Error Reporting

Chapter 7

7Ć4

Note that an ON_ERROR or an IF command may contain an embedded
command to execute another procedure. In these cases, the embedded
execute command is treated just like a nesting level. Figure 7.2 illustrates
this point for an ON_ERROR command. In this figure, an addressing
error in line 10 of procedure MAIN causes activation of the ON_ERROR
command, which calls for execution of procedure SAM. But SAM also
contains an error. The error in SAM is the last one detected, so it is the
one finally reported in the error block. Since procedure SAM is called by
the ON_ERROR command in procedure MAIN, the nesting for SAM is 2
levels deep.

Figure 7.2

Examples of ON_ERROR Nesting

MAIN

SAM

Line Number

Procedure

Word

1

8

Error Block

160

2

1

1

8

0

10031–I

10

ON_ERROR @SAM

7.2 = 1000

0

1

2

3

4

5

Contents (decimal)


$25:0 = N