User Manual

4–15Using Unscheduled Messaging
Publication 1336 FORCE–5.18 ––March, 1999
The Parameter Read Full function provides the requesting remote
I/O source with all known attributes for the parameters requested.
This information includes the parameter’s current value; descriptor;
multiply and divide value; base value; offset value; text string; file,
group, and element reference; minimum value; maximum value;
default value; and unit text string.
PLC Block Transfer Instruction Data
PLC MSG Write instruction length: 3 words
PLC MSG Read instruction length: 23 words
Message Length
3
Header
Word 1
Header
Word 1
PLC Decimal Value
768
Header
Word 2
Data
Word 3
PLC Decimal Value
768 –– Message OK
Header
Word 2
Data
Word 3
-32000 –– Message Error
Parameter Number
Parameter Number
Parameter Value or
Status Word
Descriptor
Multiply Value
Divide Value
Base Value
Offset Value
Parameter Text
Character 2 Character 1
Parameter Text
Character 4 Character 3
Parameter Text
Character 6 Character 5
Parameter Text
Character 8 Character 7
Parameter Text
Character 10 Character 9
Message Structure
Data
Word 4
Data
Word 5
Data
Word 6
Data
Word 7
Data
Word 8
Data
Word 9
Data
Word 10
Data
Word 11
Data
Word 12
Data
Word 13
Data
Word 14
0
PLC Request –– PLC Message Write
Drive Response –– PLC Message Read
Parameter Read
Parameter Read Full