vmphuc - 2018-04-20

Hi all,

I've worked with TwinCAT (Beckhoff) for about 1 year, and have some experience with it. Now, I would like to exchange to Codesys, but there are some problems causing me confusedly:
1. In TwinCAT, when using MC_Home, I have to put Calibration Sensor to INPUT for realizing calibrated position. However, in Codesys, I see that this function block does not need sensor INPUT. So, How does PLC program know when axis reach calibrated position?
And please help me know how to use MC_Home?

  1. In TwinCAT, I can divide task into 2 terms:
  2. PLC: Call motion blocks such as MC_MoveAbsolute, MC_MoveVelocity,...
  3. SAF: Interpolation task which receive information dynamic from PLC (position, velocity, acceleration, jerk) and generate trajectory to real axis.
    But I cannot find similar task in CodeSYS. Does have anyone help me how to organize tasks in CodeSYS?

  4. What is best way to exchange data between Codesys and C++ application? I know we have Shared memory solution, but is it real time capability?

Thank all of you for taking time to consider my questions.