I am trying to develop a scalable control package for specific application. Could anybody recommend a software platform of an open achitecture type to implement advanced PID control,cascade control, feed-foward control, and customized formula control. Interface with C++ is a must. GUI should be part of the software. Alarm historian should also be part of the software. All developments need to be reusable. Development code need be password protected. I do not know neither ladder logic nor any other low level languages and as a result programming language for this software need to be either very easy to learn or C. You recommendations are appreciated.