Node adjustment, Plc block transfer instruction data, Message operation – Rockwell Automation 1336T Function Block Prog. Manual, Series A/B User Manual

Page 158: Example, Write node value

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5–42

Block Transfer Services

1336 FORCE — 5.9 August 1995

The Write Node Value operation writes a value to a specified function
block node.

PLC Block Transfer Instruction Data

BTW Instruction Length:

4 Words

BTR Instruction Length:

4 Words

Header

Word 1

PLC Hex Value

8F01

8NID

Message Structure

Header

Word 2

Header

Word 3

PLC Request –– Block Transfer Write

Header Word 1

Header Word 2

Header Word 3

0

0

PLC Hex Value

0F01 –– Message OK

8F01 –– Message Error

ID

N

8NID

High Byte

Low Byte

Node Value

Data Word 4

Drive Response –– Block Transfer Read

where:

N = the node number

ID = the block ID number

Hex

Header

Word 4

Status Word

Message Operation

Word 3 specifies the function block node.

ID, specified in the low byte, indicates the block ID number.

N, specified in the high byte, indicates the node number.

The value in word 4 is written to this node. If this node is linked to
another function block node or drive parameter, the parameter output
value overwrites the node value. If the most significant bit of word 2
is set, word 4 contains an error message.

Example

In this example, a value of 4 is written to node 1 of the function
block with a block ID number of 11

Dec

(0B

Hex

).

1

0

N10:0

2

3

4

5

6

7

8

9

N10:90

BTW
Data File

BTR
Data File

Data Format

810B

4

810B

0

0

8F01

0F01

Node Adjustment:

Write Node Value

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