NT for soft real time control

The key driver for open software based controls, is the ability for products from multiple vendors from both inside and outside the industrial control arena to coexist and integrate on the same platform. Potential users are faced with a critical decision regarding the operating system strategy for open PC-architecture-based-control. Various alternatives exist in the marketplace ranging from real-time operating systems, through operating system extenders, to standard PC operating systems. Much information has been published concerning these alternatives, some without scrutiny of the alternatives, some without understanding of basic operating system behavior and some to justify limited product offerings. This paper reviews the definitions of real time control and discusses the implementation of control solutions using standard Microsoft Windows NT, and its advantages and disadvantages.