Rockwell Automation 1395 Node Adapter Board - Manual (Page 46)

Chapter 3
Functional Description
3-34
Read Trend Information This function reads the trend information from the Drive. The Trend
information is broken down into three separate blocks of data. Each block
uses the same function code with the message specifing which block is to
be read.
PLC Block Transfer Data –
BTW Instruction Length: 6
BTR Instruction Length: Refer to block information
Message Structure –
Message Header Information:
Word 1: 0
Word 2: 0
Function Code, Word 3: 270
Write Message Length, Word 4: 12 bytes
WORD
BTW BTR
1
2
3
4
NOTE: Word 4 of the BTR instruction is broken down into
two bytes. The High byte contains the status bits
per Table 3.B. The low byte contains the Drive
message length in bytes.
5
6
0
0
270
12
See Trend Number
See Block Number
0
0
270
See Note
See Block Definition
•
Trend Number – An integer number used to specify which trend buffer
the Drive will provide data for:
Trend Buffer #1 – 1
Trend Buffer #2 – 2
Trend Buffer #3 – 3
Trend Buffer #4 – 4
Block Number – An integer number used to specify which block of trend
data (from the above specified trend buffer) the Drive is to supply. The
definition of each block is as follows:
Block #0 – 0, Trend setup parameters
Block #1 – 1, Trend data samples 0 through 33
Block #2 – 2, Trend data samples 34 through 66
Block #3 – 3, Trend data samples 67 through 99