Rockwell Automation 1772-AF3,D17726.5.2 User Manual AUX FUNCT PROM - Manual (Page 23)

File Diagnostic Instruction
Chapter 4
4Ć6
Figure 4.7
Result File
Word
Location
0520
Bit Location
17 16 15 14 13 12 11 10 07 06 05 04 03 02 01 00
0 0 1 EN LS DN TR
0521
0522
1 1 1 1
1
2
work area 0
5
0
0
5
2 2
Description
Error count in
bits 13-00, 001
Address or Mismatch,
upper 3 digitd, 005
1
2
Control bits, 17-14
Status of mismatch bit 0525/02 in file of actual values
Address of Mismatch,
lower 2 digits, 25
2-digit bit number
of mismatched bit, 02
Each time the instruction finds a mismatch (at address 0515/02 in this example),
it writes the binary bit pattern of new data over old data in the result file. After
the instruction sets the done bit, it clears all data in the result file after the next
false-to-true transition of the enable bit.
NOTE: The result file must be initialized to zero before you enable the file
diagnostic instruction for the first time. If you want to change file data for a
new search, you should do so after the done bit is set.
WARNING: Do not manipulate data in the following addresses
or bits:
Data address or result address of the instruction
Control bits 16-14 in the first result word
Instruction work area, bits 16-14 in the second result word
Manipulating this data could cause the instruction to miss a mismatch or to
detect a mismatch when one did not exist. If this instruction directly or
indirectly controls an output, an inadvertent change to these values could result
in unpredictable operation and cause possible damage to equipment and/or
injury to personnel. It could also cause a run-time error.