Map I/O from the Project Explorer

  1. In the Project Explorer, expand the Controller node and the EtherCATClosed ***EtherCAT is an open, high-performance Ethernet-based fieldbus system. The development goal of EtherCAT was to apply Ethernet to automation applications which require short data update times (also called cycle times) with low communication jitter (for synchronization purposes) and low hardware costs nodes to access your devices.
  2. AKT (K-Bus) devices AKT2G (E-Bus) devices
  3. Accessing the device properties is slightly different depending upon the device.

    For AKD and AKD2G devices, double-click the drive in the project tree and select the I/O tab.

    For KAS controllers, double-click Controller Onboard I/O in the project tree.

    For I/O slices, double-click the I/O Slice under EtherCAT (AKT2G) or the Coupler entry (AKT) in the project tree. Then click the I/O tab.

    For Slice Analog I/O and thermocouples, the offset and gain parameters must be defined.

  4. There are several ways to map variables:
    • Drag and drop a variable from the Dictionary onto a table entry.
    • Use the PLC Variable Creation Wizard for Kollmorgen devices.
    • Directly map/unmap the Inputs/Outputs to PLC variables using the PLC Variable Selector.
    • Select the channel(s) to map. Selection may be done by click-dragging or shift-clicking a range of entries. The entire table may be selected by clicking on its border.

      After the selection is made, right-click and select Map or press the Enter key.
      This opens the PLC Variable Selector.


      • The Unmap command in the contextual menu is used to remove the link between the variable and the associated channel(s).
        In addition, deleting a variable from the dictionary which is mapped to the channel(s) also removes the link(s).

      Choose the variable to be linked to the channel(s) or PDO object.


      • The list of variables is filtered to display only those with relevant types.

        • PLC Variable Selector displays Read Only variables when mapping the Input channels from the I/O tab.
        • Variables assigned to the Safe Digital Input and Safe Digital Output channels must be Read Only.


  • The limitations of PLC variable mapping are:

    • Each PLC variable can be mapped to an EtherCAT I/O and exclusively to either:
      • a Controller Onboard I/O.
      • an external driver.
    • Because a variable can only be mapped to one channel or PDO object, when you link a variable to a new channel or PDO object, the previous mapping is removed (even if linked to another slice or device).
    • Individual bits within a variable can be mapped to multiple I/O channels on different devices (AKD, AKD PDMM, PCMM, or Slice).

    Example: The same PLC variable cannot be mapped to both Profinet and a Controller Onboard I/O but it is possible with a regular EtherCAT I/O.

See Also: