Rockwell Automation 1747-PT1, D1747NP002 Hand-Held Terminal - Manual (Page 382)

Chapter 27
The Status File
27–14
Address Description 5/02
5/01,
Fixed
S:5 Minor Error Bits
The bits of this word are set by the processor to indicate that a minor
error has occurred in your ladder program. Minor errors, bits 0–7,
revert to major error 0020H if any bit is detected as being set at the
end of the scan. If the processor faults for error code 0020H, you
must clear minor error bits S:5/0–7 along with S:1/13 to attempt error
recovery.
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S:5/0 Overflow Trap Bit
Read/write. When this bit is set by the processor, it indicates that a
mathematical overflow has occurred in the ladder program (see
S:0/1).
If this bit is ever set upon execution of the END, TND, or REF
instruction, a major error (0020) will be declared. To avoid this type of
major error from occurring, examine the state of this bit following a
math instruction (ADD, SUB, MUL, DIV, DDV, NEG, SCL, TOD, or
FRD), take appropriate action, and then clear bit S:5/0 using an OTU
instruction with S:5/0 or a CLR instruction with S:5.0.
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S:5/1 Reserved
• •
S:5/2 Control Register Error Bit
Read/write. The LFU, LFL, FFU, FFL, BSL, BSR, SQO, SQC, and
SQL instructions are capable of generating this error. When bit S:5/2
is set, it indicates that the error bit ER of the control instruction has
been set.
If this bit is ever set upon execution of the END, TND, or REF
instruction, a major error (0020) will be declared. To avoid this type of
major error from occurring, examine the state of this bit following a
control register instruction, take appropriate action, and then clear bit
S:5/2 using an OTU instruction with S:5/2 or a CLR instruction with
S:5.0.
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