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Read parameter data – Rockwell Automation 1395 ControlNet Communication Board User Manual

Page 33

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3–19

Configuration & PLC Interfacing

Publication 1395–5.37– March, 1999

Read Parameter Data

This function reads a parameter value from the Drive based on a
parameter number list provided by the PLC Program.

PLC Block Transfer Instruction Data –

Write

Read

Size In Elements: 5

6

Processor Type:

PLC-5

PLC-5

Destination Address:

N40:0-4

N40:0-5

Message Structure –

0

PLC Message Write

PLC Message Read

NOTE:

Word 4 of the PLC Message Read instruction is broken down
into two bytes. The High byte contains the status bits

The Low byte contains the Drive message length in bytes.

Header
Word 1

0

Function Code
514

Message Length
See Examples

Header
Word 2

Header
Word 3

Header
Word 4

Data
Word 5

Parameter #

0

Header
Word 1

0

Function Code
514

See Note

Header
Word 2

Header
Word 3

Header
Word 4

Data
Word 5

Parameter #

Message Operation – The READ PARAMETER DATA function
requests the Drive to provides a parameter data value for use in the
PLC Controller. The value is returned in Drive units and may need to
be scaled by the PLC Controller prior to being used in the Program.