ProSoft Technology MVI56-PDPMV1 - Manual (Page 47)

MVI56-PDPMV1 ♦ ControlLogix Platform Start Here
PROFIBUS DPV1 Master User Manual
ProSoft Technology, Inc. Page 47 of 255
March 22, 2011
Scenario 3: The PROFIBUS data fits into two backplane blocks (same PROFIBUS data count
per block)
For this example, we will split the PROFIBUS data evenly within two backplane
blocks, using the following backplane configuration:
For this scenario, each backplane block reserves 50 words for PROFIBUS I/O
data. The configured PROFIBUS I/O size (100 words) will not fit into one block,
so two backplane input blocks and two backplane output blocks will be required.
Backplane Block Overview
Block
Number Input/
Output Total word count
in backplane
block PROFIBUS Data
Word Count in
backplane block Initial PROFIBUS Data
Word Offset in
backplane block Last PROFIBUS Data
Word Offset in
backplane block
1 Input 58 50 0 49
2 Input 58 50 50 99
1 Output 55 50 0 49
2 Output 55 50 50 99
Note: This configuration would be inefficient and is therefore not recommended. The first example
(Scenario 1) is a more efficient configuration that will accomplish the same thing. This example is
here solely to illustrate how changing the I/O sizes without changing the amount of PROFIBUS
data to be transferred will affect the number of I/O data blocks the module will need to transfer.