Rockwell Automation 1336T ControlNet Frn1.02 Rev 1.5 - Manual (Page 117)

4–75 Using Unscheduled Messaging
Publication 1336 FORCE–5.18 ––March, 1999
The Run File Data function allows you to read the run-time data
buffer within the drive for the specified trend file.
PLC Block Transfer Instruction Data
PLC Message Write instruction length: 3 words
PLC Message Read instruction length: 35 words
Header
Word 1 Header
Word 1
Header
Word 2 Header
Word 2
Header
Word 3
Trend Number
Message Structure
Header
Word 3
Offset
PLC Decimal Value
4100
PLC Decimal Value
4100 –– Message OK
–28668 –– Message Error
Message Length
3 Message Length
35
PLC Request –– PLC Message Write
Drive Response –– PLC Message Read
Data
Word 4
Data Sample 1
Data
Word 5
Data Sample 2
•
•
Data
Word 34
Data Sample 31
Data
Word 35
Data Sample 32
•
•
•
•
•
•
•
•
•
•
Trend
Number (Bits 0 –11)
Message Operation
The Run File Data function reads the run-time buffer within the
drive for the specified trend file. This buffer is continually being
refreshed with new data when the trend is in the running state. Until
the trend is triggered, the data is placed in the stored data file. You
can use the Run File Data function to monitor data on-line. You can
read 32 data samples from the data sample pointed to by the offset.
To use the Run File Data function, you need to specify the trend
number in bits 12 through 15 and the offset into the buffer in bits 0
through 11 of the word 3 of the PMW. Therefore, you need to add
the offset value to the trend number.
Trend File
Run File Data