Normal Data Transfer; Write Block: Request From The Processor To The Module; Read Block: Response From The Module To The Processor - ProSoft Technology MVI69E-MBTCP User Manual

MVI69E-MBTCP ♦ CompactLogix Platform
Modbus TCP/IP Enhanced Communication Module
4.3

Normal Data Transfer

Normal data transfer includes the paging of the user data found in the module's
internal database (Registers 0 to 9999) and the status data. These data are
transferred through read (input image) and write (output image) blocks. The
following topics describe the structure and function of each block.

4.3.1 Write Block: Request from the Processor to the Module

These blocks of data transfer information from the processor to the module. The
structure of the output image used to transfer this data is shown below:
Offset
0
1 to (n)
(n) = 60, 120, or 240 depending on the Block Transfer Size parameter (refer to the configuration
file).
The Write Block ID is an index value that determines the location in the module's
database where the data is placed.

4.3.2 Read Block: Response from the Module to the Processor

These blocks of data transfer information from the module to the processor. The
structure of the input image used to transfer this data is shown below:
Offset
0
1
2 to (n+1)
(n) = 60, 120, or 240 depending on the Block Transfer Size parameter (refer to the configuration
file).
ProSoft Technology, Inc.
June 28, 2017
Description
Write Block ID
Write Data
Description
Read Block ID
Write Block ID
Read Data
MVI69E-MBTCP Backplane Data Exchange
Length (words)
1
(n)
Length (words)
1
1
(n)
User Manual
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