IT programming to Machine Control Programming
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This question may not be relevant here. But I am going to try it out.I am going to work as a software developer(as a fresher) in the factory automation field soon.Till now I have been a software developer in the IT field. I have done some courses in the PLC and have some experience with machine controls. 

My job profile is to do c++ multithreading and visual basic GUI programming.I have a month time to prepare regarding the things I can learn. I do not how different the c++ multithreading will be in the factory automation. I find no guidance online for c++ or other PC based programming for this field. Can someone provide me what are the difficulties or any specific things need to be know in the PC based controls? 