Download MVI71-MCM User Manual

Reference
MVI71-MCM ♦ PLC Platform
Modbus Communication Module
The user can monitor the slave status table using the Debug port .< option Slave
Status List>:
5.2.9 Command Control Blocks
Command control blocks are special blocks used to control the module or
request special data from the module. The current version of the software
supports five command control blocks: event command control, command
control, write configuration, warm boot and cold boot.
Using the Command Control Blocks
Ladder logic must be considered in order to use command control blocks. The
ladder logic moves the control block data to the correct location in order for the
data to be read by the module.
Block Transfer
The ladder logic should copy the command control block to the write block
transfer data file. For example, if using N7:310 as the write block transfer data
file, the structure would look as follows:
Offset
Data File
0
N7:310
1
N7:311
2
N7:312
3
N7:313
4
N7:314
5
N7:315
…
…
63
N7:363
ProSoft Technology, Inc.
December 28, 2007
Page 69 of 111