Modbus language objects
Implicit exchange language object for a Modbus function
At a Glance
Bit objects
This page describes all implicit exchange language objects for a Modbus function, which can be displayed or modified by the application program. See (PL7 Micro/
Junior/Pro ; Communication applications ; Volume 1).
The table below shows the different implicit exchange bit objects.
Object (1) Function
%Ixy.MOD.ERR
Module error bit
%Ixy.i.ERR
Channel error bit
Meaning
When this bit is at 1, it indicates a module error
(at least one of the channels is faulty, etc.)
When this bit is at 1, it indicates a line fault.
Key
(1) xy.i address z z z x: corresponds to the rack number y: corresponds to the module number i: corresponds to the channel number
Word objects in
Modbus master mode
The table below shows the different implicit exchange word objects.
Object (1)
%IWxy.i.0
Function
Input signals
Meaning
Common signals (2): z z z z x0 = 1: DCD signal x1 = 1: RI signal x2 = 1: CTS signal x3 = 1: DSR signal
Key
(1)
(2) z z z xy.i address x: corresponds to the rack number y: corresponds to the module number i: corresponds to the channel number only on RS232
Note: These objects are not available on the Terminal port
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Modbus language objects
Word objects in
Modbus slave mode
The language objects are identical to those of the Modbus master function. Only the objects defined in the following tables are different.
The table below shows the different implicit exchange word objects.
Object (1) Function
%IWxy.i.0
Input signals
Meaning
Specific data z x8 = 1: listen only mode
Key
(1) z z z xy.i address x: corresponds to the rack number y: corresponds to the module number i: corresponds to the channel number
Note: These objects are not available on the Terminal port
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