ProSoft MVI56E-MNETCR, User Manual

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Reference MVI56E-MNETCR ♦ ControlLogix Platform
User Manual Modbus TCP/IP Multi-Client Enhanced Communications Module for Remote Chassis
Page 110 of 161 ProSoft Technology, Inc.
5.2.2 Special Function Blocks
Special function blocks are optional blocks used to request special tasks from the
module.
Initialize Output Data Blocks (1000 to 1124)
Use the Initialize Output Data parameter in the configuration to bring the module
to a known state after a restart operation. If the Initialize Output Data parameter
is enabled, when the module performs a restart operation, it will request blocks of
output data from the
ReadData array in the processor to initialize the Read Data
area of the module’s internal database.
CLX Processor
Read
Tags
Local:X:I
Local:X:O
MNET Module
Normal Data transfer
Modbus
Output
Modbus
Input
Write
Tags
CLX Processor
Read
Tags
Local:X:I
Local:X:O
MNET Module
Initialize Output Data transfer
Modbus
Output
Modbus
Input
Write
Tags
Block Request from Module to Processor
Word Offset Description Length
0 1000 to 1124 1
1 to 40 Spare 40
41 1000 to 1124 1
The block number in word 0 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.
Block Response from Processor to Module
Word Offset Description Length
0 1000 to 1124 1
1 to 40 Output Data to preset in module. 40
41 Spare 1