Rockwell Automation 1336T PLC Comm. Adapter, Series B, FRN 2.xx-3.xx - Manual (Page 203)

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Publication 1336 FORCE–5.13 –– September, 1998
The Maximum Trend Size Available function allows you to
determine the size of the trend buffer. This function always returns
500.
PLC Block Transfer Instruction Data
BTW instruction length: 3 words
BTR instruction length: 3 words
Header
Word 1 Header
Word 1
Header
Word 2 Header
Word 2
Header
Word 3
Maximum Trend Size
Message Structure
Header
Word 3
0
PLC Decimal Value
4097
PLC Decimal Value
4097 –– Message OK
–28671 –– Message Error
Message Length
3 Message Length
3
PLC Request –– Block Transfer Write
Drive Response –– Block Transfer Read
Message Operation
You can use the Maximum Trend Size Available function to
determine the size of the trend buffer. This function always returns
500.
Example
In this example, a Maximum Trend Size Available request was sent
to the drive. The drive returned a value of 500 in word 3.
1 0
N10:10
2 3 4 5 6 7 8 9
N10:90
BTW
Data File
BTR
Data File
Data Format
0
500
3
3
4097
4097
Trend File
Maximum Trend Size Available