ProSoft Technology MVI69E-MBS - Manual (Page 143)

MVI69E-MBS ♦ CompactLogix Platform Reference
Communication Module User Manual
ProSoft Technology, Inc. Page 143 of 162
January 6, 2014
7.4.14 Pass-through Formatted Block for Functions 6 and 16 with
Float Data Block
Block 9957: Pass-through Formatted Block for Functions 6 and 16 with Float
Data Block
Block 9957: Request from Module to Processor
Offset Description
0 Read Block ID: 9957
1 Write Block ID: 9957
2 Number of word registers in Modbus data set
3 Starting address for Modbus data set
4 to (n+1) Data (Length in words = n - 2)
Where n = 60, 120, or 240 depending on the Block Transfer Size parameter.
The ladder logic is responsible for parsing and copying the received message
and performing the proper control operation as expected by the Master device.
The processor must then respond to the Pass-through block with a write block
with the following format.
Block 9957: Response from Processor to Module
Offset Description
0 Write Block ID: 9957
1 to n Spare (Length in words = n - 2)
This informs the module that the command has been processed and can be
cleared from the pass-through queue.