Modbus Port X Commands - ProSoft Technology CompactLogix MVI69E-MBS User Manual

MVI69E-MBS ♦ CompactLogix™ Platform
Modbus Serial Enhanced Communication Module

3.2.3 Modbus Port x Commands

This section defines the master command list specifications for a Master port. The
information in this section applies to both MBS P
In the ProSoft Configuration Builder tree view, double-click the M
C icon.
OMMANDS
In order to interface the MVI69E-MBS with Modbus slave devices, you must create a
command list. The commands in the list specify the slave device to be addressed, the
function to be performed (read or write), the data area in the device to interface with and
the registers in the internal database to be associated with the device data.
The Master command list supports up to 250 commands. The command list is
processed from top (Command #0) to bottom.
Read commands are executed without condition. You can set write commands to
execute only if the data in the write command changes (Conditional Enable). If the
register data values in the command have not changed since the command was last
issued, the command is not executed. You can use this feature to optimize network
performance.
The MVI69E-MBS Master (and Slave) communication drivers support several data read
and write commands. When a command is configured, the type of data (bit, 16-bit
integer, 32-bit float, etc), and the level of Modbus support in the slave equipment needs
to be considered.
ProSoft Technology, Inc.
Configuring the MVI69E-MBS Using PCB
1 and MBS P
ORT ORT
ODBUS
User Manual
2.
P
ORT X
Page 44 of 159