Integrating MotionLinx with TwinCAT /

MotionLinx Data Objects

The data exchange between remote MotionLinx-Ai Module and MotionLinx-IO Module devices and the PC based TwinCAT controller is CANOpen over EtherCAT (CoE). This protocol provides for cyclic data exchange between a “Master” controller (PC based TwinCAT) and multiple “Slave” devices (MotionLinx-Ai Module / MotionLinx-IO Module devices). The data object types supported by MotionLinx-Ai Module and MotionLinx-IO Module units are CoE Process Data Objects (PDOs) and Service Data Objects (SDOs).

*Please consult CoE documentation for further details of the CANOpen network protocol.

Process Data Objects (PDO)

• Transmit PDOs send data from the MotionLinx-Ai Module / MotionLinx-IO Module modules to the Master Controller
• Receive PDOs send data from the Master Controller to the MotionLinx-Ai Module / MotionLinx-IO Module modules

*Each PDO has a number of SubIndex objects that are fundamental data types such as SINT, INT, DINT, etc. It is these SubIndexes that are assigned to variable tags and used in your program logic.

MotionLinx-Ai Module Module 2 Transmit PDOs and 3 Receive PDOs
MotionLinx-IO Module Module 1 Transmit PDO and 1 Receive PDO

Service Data Objects (SDO)

SDOs are used for data that is not intended to be cyclic like PDOs. The use of SDOs can be thought of as “lower priority” and are invoked on an “as needed” basis. For example, setting up the initial configuration or the reading of non-transitory data from the module are typical SDOs provided. SDOs can be read or write.

*Please consult your TwinCAT or other IDE for details on specific instructions to read/write SDO data.

Learn More:

MotionLinx-Ai Transmit PDOs

MotionLinx-Ai Receive PDOs

MotionLinx-IO Transmit PDO

MotionLinx-IO Receive PDO

MotionLinx-Ai SDOs

MotionLinx-IO SDO