Rockwell Automation 1772-LS_LSP,D17726.8.6 PROG/OPER MANUAL-MINI PLC-2/05 User Manual
Page 113

Data Transfer File Instructions
Chapter 11
11-4
For each true rung condition, the instruction is enabled. The number of
words equal to the rate per scan is operated upon during one scan. The
process is repeated over a number of consecutive scans until the entire file
has been operated upon. Once the file instruction is enabled it remains
enabled for the number of scans necessary to complete the operation. The
rung could become repeatedly false and true during this time without
interrupting the operation of the instruction.
At the time of completion, if the rung is true, the enable bit (bit 17) and the
done bit (bit 15) are both set. If the rung is false, the enable bit is reset
after the last group of words is operated upon. At the same time, the done
bit is set and stays set for one scan. During the next scan the done bit is
reset, and the counter is reset to position 001.
Incremental Mode
In the incremental mode, the rate per scan is equal to 0. This means that
upon each false-to-true transition one word is operated upon per scan, then
the counter increments to the next position. When the rung is true the
enable bit (bit 17) is set. After the last word in the file has been operated
upon, the done bit (bit 15) is set. When the rung goes false, the done and
enable bits are reset (after the last word has been operated upon), and the
counter is reset to position 001. If the rung remains true for more than one
scan, the operation does not repeat. The operation only occurs in the scan
in which the false-to-true transition occurs.
To change from one mode to another, use Table 11.A to determine
the values.
Table 11.A
Changing Modes
To change
Enter the Rate per Scan Value
Complete to Distributed Complete
001 thru 006
Distributed Complete to Incremental
000
Distributed Complete to Complete
007
Incremental to Complete
007