Accessing Device DDT Variables
Original instructions
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Introduction
You can access the device DDT for EtherNet/IP and Modbus TCP devices that are scanned by the Ethernet communication module after you perform one of these tasks:
Access the Device DDT Variables
Access the device DDT for the Ethernet communication module in Control Expert:
Step
Action
1
Open the Control Expert Project Browser (Tools → Project Browser).
2
Expand (+) Variables & FB instances.
3
Double-click Device DDT Variables.
You can add the variable to an Animation Table to read the status and set the device control bit.
NOTE: The red arrow and lock icons in the Device DDT table indicate that the variable name was auto-generated by Control Expert based on the configuration of the communication module, local slave, or distributed device. (You cannot edit the variable name.)
This table describes the input and output bits associated with the EtherNet/IP and Modbus TCP devices:
Name
Description
Freshness
This is a global bit:
  • 1: All input objects below (Freshness_1, Freshness_2, etc.) for the associated device are true (1) and provide up-to-date data.
  • 0: One or more inputs (below) is not connected and does not provide up-to-date data.
Freshness_1
These bits represent individual input objects for the device:
  • 1: The input object in this row is connected and provides up-to-date data.
  • 0: The input object is not connected and does not provide up-to-date data.
Freshness_2
These bits represent individual input objects for the device:
  • 1: The input object in this row is true (1) and provides up-to-date data.
  • 0: The input object is not connected (0) and does not provide up-to-date data.
Freshness_3
...
(available)
The rows after the Freshness data are organized in groups of Inputs and Outputs that have user-defined names. The number of input and output rows depends on the number of input and output requests configured for a particular device.