Hi friends, I have several questions that are related to develop servo controllers and develop servo drivers, so if you know something or you know one good website with an article that talk about one thing that is correlated to one of these things so I will glad if you can write it in this a replay. 1. What are the servo controller interfaces different for different encoders that input to the servo controller? 2. How to develop and build I\O for servo controllers for different kinds of I\O (Input \ Output)? 3. What are the different kinds of communication that controllers use? And I search after information of these kinds of communications. 4. I search after information about control algorithms like the equations for tracking in the close loop, solving the controller, calculation of the close loop of the system, automated PID extended, compensation and cyclic phenomenon.