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Distributed complete mode – Rockwell Automation 1772-LP3 PLC - 2/30 Programmable Controller Programming and Operations Manual User Manual

Page 222

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Data Transfer File Instructions

Chapter 12

12Ć7

Figure 12.6

Status Bits for Complete Mode

Rung Condition

Enable Bit (17)

Done Bit (15)

Instruction Operation

1

Scan

A = Status bits are reset to zero and

counter is reset to word 1.

Distributed Complete Mode

In cases where is is not necessary that the file operation be completed in
one program scan, it may be advantageous to distribute the file operation
over several program scans. This is to avoid overextending the scan time of
any one program scan. This scan can be done by selecting the distributed
complete mode. Any rate per scan, R, can be chosen where 0length.

When the rung containing the file instruction goes true, the number of
words equal to the rate per scan is operated upon during one scan. This
process is repeated over a number of scans, until the entire file has been
operated upon. Figure 12.7 shows the operation of the file instruction in
the distributed complete mode.