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Rockwell Automation 1771-IL/B , D17716.5.91 ISOLATED ANALOG INPUT Module User Manual

Page 59

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Block Transfer (Mini–PLC–2 and
PLC–2/20 Processors)

Appendix D

D-2

Rungs 2 and 3: These output energize instructions (012/01 and 012/02) define
the number of words to be transferred. This is accomplished by setting a binary
bit pattern in the module’s output image table control byte. The binary bit
pattern used (bits 01 and 02 energized) is equivalent to 6 words or channels, and
is expressed as 110 in binary notation.

Rung Summary: Once the block transfer read operation is complete, the
processor automatically sets bit 07 in the input image table status byte and
stores the block length of the data transferred.

Figure D.1
Multiple GET Instructions (Mini-PLC-2 and PLC-2/20 Processors Only)

Data Table

07

1

R

Control
Byte

010

012

017

027

030

060

065

110

112

117

130

Output Image Table Control

Byte Contains Read
Enable Bit and Block

Length in Binary Code

Data Address
Contains Module

Address in BCD

Input Image Table
Status Byte
Contains Done Bit

Storage Location
Contains File
Address in BCD

R = Read 07 = Bit

1

2

0

07

1

R

Status

Byte

0

6

0

Output
Image Table

Timer/Counter

Accumulated
Values Area

Input

Image

Table

Timer/Counter

Preset

Values Area

First Address,
Destination of

Transferred Data

12172

113

02

012

07

G

G

012

01

012

02

030

130

120

060

Rung 1

Rung 2

Rung 3

Multiple GET Instructions