Parameter write, Plc block transfer instruction data, Message operation – Rockwell Automation 1336T PLC Comm. Adapter, Series B, FRN 2.xx-3.xx User Manual

Page 159: Example, Parameter value write

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7–13

Publication 1336 FORCE–5.13 –– September, 1998

This message sent by the PLC Communications Adapter Board reads
the 16–bit parameter data value for the parameter number selected.

PLC Block Transfer Instruction Data

BTW instruction length:

4 words

BTR instruction length:

4 words

Message Length

4

Header

Word 1

Header

Word 1

PLC Decimal Value

-31999

Header

Word 2

Parameter Number

Data

Word 3

PLC Decimal Value

769 –– Message OK

Header

Word 2

Data

Word 3

Parameter Number

-31999 –– Message Error

Data

Word 4

Parameter Value

Data

Word 4

Message Structure

0

PLC Request –– Block Transfer Write

Parameter Value or

Status Word

Drive Response –– Block Transfer Read

Message Operation

The Parameter Value Write function specified in the BTW sends a
new value (specified in word 4 of the BTW header message) to the
parameter specified in the BTW header word 3. The value must be in
device units.

If an error has occurred:

Word 2 of the response returns a value of -31999.

Word 4 contains a status code.

Example

In this example, a value of 4096 was sent to parameter 20. 4096 is in
drive units and indicates a value of 100% of rated drive volts as
defined by parameter 147, Drive Rated Volts.

1

0

N10:10

2

3

4

5

6

7

8

9

N10:90

BTW
Data File

BTR
Data File

Data Format

20

4096

20

4096

4

0

-31999

769

➀ These values vary depending on parameters and products.

Parameter Write

Parameter Value Write

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