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MVI56E-MNETR ♦ ControlLogix Platform
Reference
Modbus TCP/IP Interface Module with Reduced Data Block
User Manual
ProSoft Technology, Inc.
Page 117 of 175
June 14, 2011
The block number in word 20 of the block determines the data set of up to 40
output words to transfer from the processor. Ladder logic in the processor must
recognize these blocks and place the correct information in the output image to
be returned to the module. The following table describes the structure of the
response block.
Offset
Description
Length
0
1000 to 1124
1
1 to 40
Output Data to preset in module.
40
41
Spare
1
Special Function Blocks
Special function blocks are optional blocks used to request special tasks from the
module.
Note:
Event Commands and Command Control are not needed for normal Modbus command list
polling operations and are needed only occasionally for special circumstances.
Important:
Each command defined in the command list is controlled by the ladder logic. The Write
Command Bits parameter must be set in ladder logic to allow the command to be sent out on the
Modbus TCP/IP network.