FlexOS

FlexOS was a modular, real-time, multiuser, multitasking operating system that Digital Research's Flexible Automation Business Unit in Monterey, California built in 1985, formally adopting the FlexOS name on October 1, 1986 as it moved on from earlier versions of Concurrent DOS. It targeted computer-integrated manufacturing, laboratory, retail and financial markets, and Digital Research wrote it in C so it could be ported across processor families including the Intel 80186, 80286 and 80386 and Motorola's 68000 series, giving it very low interrupt latency and fast context switching for industrial use. By 1990 and 1991 its customers included FANUC, IBM, Siemens and Toshiba. Novell acquired Digital Research in July 1991 and sold FlexOS on to Integrated Systems Inc. for three million dollars in 1994; its final release was version 2.33 in May 1998. This description is adapted from Wikipedia contributors under CC BY-SA 4.0; changes were made. https://creativecommons.org/licenses/by-sa/4.0/