Master Variables (Slave Data Points on the Master)

Clicking [Map] applies the slave data points for the master and displays them as master variables on the left side in tabular form as follows:

“Modbus Master Variables” Tab – Slave Data Points on the Master (Left Side)
Parameters	Description
Data point (slave)	Name and path of the slave data points on the master
Variable	Variable name and path on the master Variants are normally either manual or automatic.
	Automatic	A variable is created according to the variable path on the master.
	Manual	The variable is entered by the user. This can be an existing variable or one created by CODESYS.
Mapping	Displays which variable is new and which variable already exists:
		The variable is not yet available, is newly created and can then be used in the entire project.
		An existing variable is used for mapping.
Data type	Selection field for selecting the (slave) data type
T [ms]	Cycle time when accessing the data point
T [ms]	Access to the variables of the Modbus slave are defined:
Access	ReadOnly	Master reads the slave output.
	WriteOnly	Master writes the slave input.
	ReadWrite	Master can write/read the slave input/output.
Trigger	The timed access is defined. The selection depends on the access setting.
	Cyclic	Variable is processed cyclically.
	OnValue Change	Variable is written on change of value (only with “WriteOnly” and “ReadWrite”).

Right-clicking on the master variable or output slave data point opens a context menu:

Slave Variables Context Menu
Symbol	Function	Description
	Delete	Deletes the slave data point on the master. The master variable is also deleted unless it is a global variable.
	Reset	Reset variable to “automatic value
	Transfer	Accept the value of the cell for all selected rows (T [ms], trigger, access)