ProSoft Technology MVI69E-MBTCP - Manual (Page 139)

MVI69E-MBTCP ♦ CompactLogix Platform Reference
Modbus TCP/IP Enhanced Communication Module User Manual
ProSoft Technology, Inc. Page 139 of 150
May 20, 2015
7.4.13 Pass-Through Formatted Block for Functions 6 and 16 with
Float Data Block (9957)
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 53 Modbus Data
54 to (n-1) Spare
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 client device.
The processor must then respond to the Pass-Through block with a write block
with the following format. This informs the module that the command has been
processed and can be cleared from the Pass-Through queue.
Block 9957: Response from Processor to Module
Offset Description
0 Write Block ID 9957
1 to n Spare (Length in words = n - 2)
7.4.14 Pass-Through Formatted Block for Function 5 (9958)
Block 9958: Request from Module to Processor
Offset Description
0 Read Block ID 9958
1 Write Block ID: 9958
2 Number of word registers in the Modbus data set
3 Starting address for the Modbus data set
4 to 53 Modbus Data
54 to (n-1) Spare
Where n = 60, 120, or 240 depending on the Block Transfer Size parameter.