Rockwell Automation 1336T PLC Comm. Adapter, Series B, FRN 2.xx-3.xx - Manual (Page 150)

7–4
Publication 1336 FORCE–5.13 –– September, 1998
This message is sent by the PLC Communications Adapter Board
and reads the 16–bit parameter data value for the parameter number
selected.
PLC Block Transfer Instruction Data
BTW instruction length: 3 words
BTR instruction length: 4 words
Message Length
3
Header
Word 1 Header
Word 1
PLC Decimal Length
769
Parameter Number
PLC Decimal Value
769 –– Message OK
Parameter Value or
Status Word
Parameter Number
-31999 –– Message Error
Message Structure
Header
Word 2
Data
Word 3
Header
Word 2
Header
Word 3
Header
Word 4
0
PLC Request –– Block Transfer Write
Drive Response –– Block Transfer Read
Message Operation
The Parameter Value Read function specified in the BTW reads a
parameter value from the drive and places that value (or an error
code) in word 4 of the BTR data file. The value shown is in device
units.
If an error has occurred:
•
Word 2 of the BTR returns a value of -31999.
•
Word 4 contains the status code.
Parameter Read
Parameter Value Read