Hard Real-time with RTX on Windows NT

For a variety of reasons, Microsoft Windows NT is increasingly being considered as a platform for deployment of real-time systems. In order to meet the stringent latency requirements of hard real-time systems, it is necessary to augment the capabilities of Windows NT. We examine VenturCom's RTX, which provides a real-time subsystem running on Windows NT. It implements deterministic scheduling of real-time threads, inter-process communication mechanisms between the real-time environment and the native NT environment, and other extensions to Windows NT which are often found in specialized real-time operating systems. We discuss how the components of RTX provide these features, explore current results and experiences, and point out possible future directions for enhancement.