506 Rockwell Automation Publication 1756-RM003N-EN-P - October 2011
Chapter 13 Special Instructions (FBC, DDT, DTR, PID)
Postscan The rung-condition-out is set to false.
Condition: Relay Ladder Action
Compare.POS ≥
Compare.LEN
Yes
No
Compare.POS = compare.LEN
Compare.DN bit is set.
Compare
Goto
Exit
Source[compare.POS] =
Reference[compare.POS]
No
Yes
Examine result.DN
bit.
Result.DN = 1
Result.DN = 0
Compare.POS =
Compare.POS + 1
Compare.FD bit is set.
Reference[compare.POS]
= Source[compare.POS]
Result.DN bit is cleared.
Result.POS value is
cleared.
Result.POS < 0
Yes
No
Result.LEN ≤ 0
Yes
no
Compare.ER bit is set.
Goto
Exit
Yes
no
Major Fault
Result[result.POS] = Compare.POS
Result.POS = Result.POS + 1
Result.POS ≥
Result.LEN
No
Yes
Result.DN bit is set.
page 505
page 498
Result.POS >
Size of result array