Addressing

Property

Description

Name

Any name can be chosen; ATTENTION: the name must be unique within each project.

Identification

Any text can be entered here, e.g. for resource labels, comments ...

Net address

Bus address or net address of the variable.

When using serial communication, this address corresponds to the Modbus address of the PLC; for communication via Ethernet, it corresponds to the connection configuration in the driver. This defines the PLC/connection on which the variable resides.

If a gateway (TCP/IP) is used for communicating with the Modbus stations, you have to create a separate TCP/IP connection for each Modbus station. Use the address of the gateway as the IP address and the address of the Modbus station as the Net address of the connection and in the variables.

The highest possible Modbus address, according to the protocol specification, is 247. The address 0 is used for Broadcast messages (write only).

Data block

not used for this driver

Offset

Offset of the variable; the memory address of the variable in the PLC. Configurable [0.. 4294967295]

Alignment

The driver uses word-based addressing (16 bit). If only one Byte is read, you can configure here whether the HiByte or the LowByte will be addressed.

Bit number

Number of the bit within the configured offset.

Valid input [0.. 65535] Working range [0-15]

String length

Only available for String variables: Maximum number of characters that the variable can take.

Driver object type

Depending on the employed driver, an object type is selected during the creation of the variable; the type can be changed here later.

Data type

Data type of the variable, which is selected during the creation of the variable; the type can be changed here later.

ATTENTION: If you change the data type later, all other properties of the variable must be checked and adjusted, if necessary.