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Plcć5 family processors – Rockwell Automation 1771-IJ_IK IK ENCODER/COUNTER MODULES User Manual

Page 53

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6–9

Block Transfer Programming

Publication 1771ĆUM006B-EN-P - June 2002

PLCĆ5 Family Processors

You can use the following ladder logic with PLC-5 processors. This
program assumes that your application requires a single BTR and
BTW to pass data between the processor and the module.

Ladder logic alternates the execution of BTR and BTW instructions.
The processor checks data validity before accepting read data, and
sets one enable bit at a time.

Refer to Figure 6.7 for generalized ladder logic, and to Figure 6.8 for
example ladder logic with entered values.

Figure 6.7

Generalized Ladder Logic for PLCĆ5 Block Transfer

BTW

EN

BTR

EN

1

2

15047

BTW

Control Block
Data File

yyy

xxx

Continuous

no

BTR

Control Block
Data File

aaa

zzz

Continuous

no

BTW

EN

BTR

EN