FlexOS is a discontinued modular real-time multiuser multitasking operating system (RTOS) designed for computer-integrated manufacturing, laboratory, retail and financial markets. Developed by Digital Research's Flexible Automation Business Unit in Monterey, California, in 1985.[2][3]
The system was considered to become a successor of Digital Research's earlier Concurrent DOS, but with a new, modular, and considerably different system architecture and portability across several processor families.[4] Still named Concurrent DOS 68K and Concurrent DOS 286, it was renamed into FlexOS on 1 October 1986 to better differentiate the target audiences.
FlexOS was licensed by several OEMs who selected it as the basis for their own operating systems like 4680 OS, 4690 OS, S5-DOS/MT and others. Unrelated to FlexOS, the original Concurrent DOS system architecture found a continuation in successors like Concurrent DOS XM and Concurrent DOS 386 as well.
Overview
Concurrent DOS 286, Concurrent DOS 68K and FlexOS were designed by Francis "Frank" R. Holsworth (using siglum FRH).[5][6] Like Portable CP/M, Concurrent DOS 286, Concurrent DOS 68K and Concurrent DOS V60,[1][7] FlexOS was written in C for higher portability across hardware platforms, and it featured very low interrupt latency and fast context switching.[8]
In May 1987, FlexOS version 1.31 was released for 80286 machines.[13] The developer version required an IBM PC/AT-compatible machine with 640KB of conventional and 512KB of extended memory, and either a (monochrome) CGA or an EGA graphics adapter.
FlexOS supported a concept of dynamically loadable and unloadable subdrivers, and it came with driver prototypes for floppies, hard disks, printers, serial interfaces, RAM disks, mice and console drivers.
During boot, the FLEX286.SYS kernel would load the resource managers and device drivers specified in the CONFIG.SYS binary file (not to be mixed up with the similarly named CONFIG.SYS configuration file under DOS), and its shell (COMMAND.286) would execute a CONFIG.BAT startup batch job instead of the common AUTOEXEC.BAT.
FlexOS's optional DOS emulator provided limited PC DOS 2.1 compatibility for DOS .COM and .EXE programs.[9] Certain restrictions applied in "8086 emulation mode" since these programs were executed in the processor's protected mode. Due to bugs in earlier steppings of the Intel 80286, the FlexOS 286 DOS front-end required at least the 80286 E2 stepping to function properly (see LOADALL).[9] These problems had already caused delays in the delivery of Concurrent DOS 286 earlier.[14][15]
Graphics Environment Manager (GEM) Graphic User Interface (GUI) in 1985
The system optionally supported a multitasking GEMVDI for graphical applications.[9][16]
FlexOS 1.31 could be linked with none, either or both of these two modules. FlexOS 1.31 also supported FlexNet.
By June 1987 there were also versions 1.0 of FlexOS 386 (for hosts) and FlexOS 186 (for remote cell controllers).[8] FlexOS 386 provided a windowing feature, and offered PC DOS 3.2 and GEM compatibility.[8]
FlexOS286 and FlexOS386 versions 2.0 were registered on 3 July 1989.
When Novell decided to abandon further development of the various Digital Research operating systems such as Multiuser DOS (a successor to Concurrent DOS) and Novell DOS (a successor to DR DOS), they sold FlexOS off to the Santa Clara, California-based Integrated Systems Inc. (ISI) for US$3million in July 1994.[22] The deal comprised a direct payment of half this sum as well as shares representing 2% of the company. The company already had pSOS+, another modular real-time multitasking operating system for embedded systems, but they continued to maintain FlexOS as well.[22] FlexOS version 2.33 was current as of May 1998 and with FlexOS 2.34 to be released soon after with added support for faster CPUs, 64 MB of memory, EIDE and ATAPI CDROM drives.
Integrated Systems was bought by their competitor Wind River Systems in February 2000.
Commands
The following list of commands is supported by FlexOS:[23]
Named IBM 4680 OS Version 1, IBM originally chose DR Concurrent DOS 286 as the basis of their IBM 4680 computer for IBM Plant System products and Point-of-Sale terminals in 1986.[32][10][4][33] The last release of the IBM 4680 OS has been Version 4, before it was replaced by IBM 4690 Version 1.[34]
In July 1993, IBM announced the adoption of FlexOS version 2.32 as the basis of their IBM 4690 OS Version 1, to be pre-released on 24 September 1993[33] and generally made available from 25 March 1994.[34][35] FlexOS 2.32 supported 286 and 386 modes, had more efficient memory management, better console and pipe systems, and brought overall quality and performance improvements compared to the version that came with IBM 4680 OS Version 4.[34] Further, it removed limits on the number of applications running concurrently due to its more efficient use of KOSPOOL.[34]
According to "The Year of the Store?", IHL Consulting Group/RIS News, IBM 4690 OS still had a market share of 12% in the POS register/client market in June 2005, when IBM was starting to phase it out in favour to IBM Retail Environment for SUSE (IRES).[33]
IBM continued to maintain 4690 OS up to April 2015, with the most recent version released by IBM in May 2012 being IBM 4690 OS Version 6 Release 3.
Toshiba released Toshiba 4690 OS Version 6 Release 4 in January 2014 and Version 6 Release 5 in January 2016.
Siemens S5-DOS/MT
Siemens used and still maintains FlexOS in their factory automation equipment as well. For example, their Simatic S5 STEP-5 operating system S5-DOS/MT is based on FlexOS 386 with X/GEM, FlexNet and Btrieve, whereas the smaller S5-DOS system, also present on these systems, is a variant of Digital Research's Personal CP/M-86.
Siemens industrial systems like COROS LS-B/FlexOS, COROS OS-B/FlexOS, GRACIS/FlexOS, Teleperm M[de] OS-525 were FlexOS and X/GEM-based.
Computers such as the Sicomp[de] PC 16-20 and the PC 32 series were available with FlexOS as well.
CTM
The Japanese post office shared terminals CTM[ja] III and CTM IV were based on FlexOS.
The Intel 80286 is a 16-bit microprocessor that was introduced on February 1, 1982. It was the first 8086-based CPU with separate, non-multiplexed address and data buses and also the first with memory management and wide protection abilities. The 80286 used approximately 134,000 transistors in its original nMOS (HMOS) incarnation and, just like the contemporary 80186, it can correctly execute most software written for the earlier Intel 8086 and 8088 processors.
In computer data storage, drive letter assignment is the process of assigning alphabetical identifiers to volumes. Unlike the concept of UNIX mount points, where volumes are named and located arbitrarily in a single hierarchical namespace, drive letter assignment allows multiple highest-level namespaces. Drive letter assignment is thus a process of using letters to name the roots of the "forest" representing the file system; each volume holds an independent "tree".
Xenix was a version of the Unix operating system for various microcomputer platforms, licensed by Microsoft from AT&T Corporation in the late 1970s. The Santa Cruz Operation (SCO) later acquired exclusive rights to the software, and eventually replaced it with SCO UNIX.
GEM is a discontinued operating environment released by Digital Research in 1985. GEM is known primarily as the native graphical user interface of the Atari ST series of computers, providing a WIMP desktop. It was also available for IBM PC compatibles and shipped with some models from Amstrad. GEM is used as the core for some commercial MS-DOS programs, the most notable being Ventura Publisher. It was ported to other computers that previously lacked graphical interfaces, but never gained traction. The final retail version of GEM was released in 1988.
Digital Research, Inc. was a privately held American software company created by Gary Kildall to market and develop his CP/M operating system and related 8-bit, 16-bit and 32-bit systems like MP/M, Concurrent DOS, FlexOS, Multiuser DOS, DOS Plus, DR DOS and GEM. It was the first large software company in the microcomputer world. Digital Research was originally based in Pacific Grove, California, later in Monterey, California.
MP/M is a discontinued multi-user version of the CP/M operating system, created by Digital Research developer Tom Rolander in 1979. It allowed multiple users to connect to a single computer, each using a separate terminal.
NetWare is a discontinued computer network operating system developed by Novell, Inc. It initially used cooperative multitasking to run various services on a personal computer, using the IPX network protocol.
Star Trek is the code name that was given to a secret prototype project, running a port of Macintosh System 7 and its applications on Intel-compatible x86 personal computers. The project, starting in February 1992, was conceived in collaboration between Apple Computer, who provided the majority of engineers, and Novell, who at the time was one of the leaders of cross-platform file-servers. The plan was that Novell would market the resulting OS as a challenge to Microsoft Windows, but the project was discontinued in 1993 and never released, although components were reused in other projects. The project was named after the Star Trek science fiction franchise with the slogan "To boldly go where no Mac has gone before".
TopView is the first object-oriented, multitasking, and windowing, personal computer operating environment for PC DOS developed by IBM, announced in August 1984 and shipped in March 1985. TopView provided a text-mode operating environment that allowed users to run more than one application at the same time on a PC. IBM demonstrated an early version of the product to key customers before making it generally available, around the time they shipped their new PC AT computer.
Virtual DOS machines (VDM) refer to a technology that allows running 16-bit/32-bit DOS and 16-bit Windows programs when there is already another operating system running and controlling the hardware.
Multiuser DOS is a real-time multi-user multi-tasking operating system for IBM PC-compatible microcomputers.
LOADALL is the common name for two different, undocumented machine instructions of Intel 80286 and Intel 80386 processors, which allow access to areas of the internal processor state that are normally outside of the IA-32 API scope, like descriptor cache registers. The LOADALL for 286 processors is encoded 0Fh 05h, while the LOADALL for 386 processors is 0Fh 07h.
4690 Operating System is a specially designed point of sale (POS) operating system, originally sold by IBM. In 2012, IBM sold its retail business, including this product, to Toshiba, which assumed support. 4690 is widely used by IBM and Toshiba retail customers to run retail systems which run their own applications and others.
In computing, ren is a command in various command-line interpreters (shells) such as COMMAND.COM, cmd.exe, 4DOS, 4NT and Windows PowerShell. It is used to rename computer files and in some implementations also directories. It is analogous to the Unix mv command. However, unlike mv, ren cannot be used to move files, as a new directory for the destination file may not be used. Alternatively, move may be used if available. On versions of MS-DOS that do not support the move command, the user would simply copy the file to a new destination, and then delete the original file. A notable exception to this rule is DOSBox, in which ren may be used to move a file, since move is not supported.
In computing, type is a command in various command-line interpreters (shells) such as COMMAND.COM, cmd.exe, 4DOS/4NT and Windows PowerShell used to display the contents of specified files on the computer terminal. The analogous Unix command is cat.
This article presents a timeline of events in the history of 16-bit x86 DOS-family disk operating systems from 1980 to present. Non-x86 operating systems named "DOS" are not part of the scope of this timeline.
DOS 286 or DOS/286 may refer to:
MS-DOS 4.0 was a multitasking release of MS-DOS developed by Microsoft based on MS-DOS 2.0. Lack of interest from OEMs, particularly IBM, led to it being released only in a scaled-back form. It is sometimes referred to as European MS-DOS 4.0, as it was primarily used there. It should not be confused with PC DOS 4.00 or MS-DOS 4.01 and later, which did not contain the multi-tasking features.
↑ "Novell Announces RTOS Vendor Program Which Brings Integrated Networking Solutions to the Embedded Systems Marketplace" (Press Release). Novell. 1995-05-23. Because Novell used Integrated Systems' FlexOS during the development and testing of NEST, we are in the unique position of supporting it through both our real-time product lines pSOSystem for deeply embedded markets, and FlexOS for point of sale," said Moses Joseph, vice president of marketing for Integrated Systems. "Developers using the FlexOS development kit and the expanded pSOSystem/NEST package for everything from home security and entertainment to office automation and global communications applications, now have quick and easy access to the widest variety of standard networking protocols.
1 2 Heller, Robert; Taetsch, Tom (1987-01-29) [1987-01-26, 1987-01-27]. "Concurrent DOS 68K: The word from DRI". Newsgroup:mod.computers.68k. Archived from the original on 2020-01-03. Retrieved 2010-01-03. […] it is possible to purchase an implementation of CDOS-68K for the Motorola VME-10. The media it comes on is Motorola VME-10 5.25" floppies. […] CDOS-68K is the 68K version of CDOS-286 (which has now been updated and renamed to FlexOS 286). This CDOS-286/68K operating system was designed specifically to provide easy addition and deletion of I/O drivers and sub-drivers. Drivers can either be linked in to the O/S or kept external and dynamically loaded at boot time. […] CDOS-68K is at revision level 1.2, while CDOS-286 was upgraded to rev level 1.3 (at which point it became FlexOS 286). The significance of this to you is that no enhancements or maintenance of the 68K version is planned in the near future (unless a "major" OEM contract should happen). So the 68K O/S is pretty much being sold only on an "as is" basis. […]
↑ Swaine, Michael (1982-04-05). "Homebrew Computer Club views Intel's superchip". InfoWorld. 4 (13). Palo Alto, CA, USA: 4. Archived from the original on 2020-01-07. Retrieved 2020-01-07. […] Digital Research is producing an operating system for the 286. MP/M-286 will take advantage of the processor's memory management and protection and virtual memory support. Digital Research is promising "complete" compatibility with its MP/M-86 and CP/M-86 for the 8086 processor. Intel is supplying Digital Research with the hardware to develop and test MP/M-286. […]
↑ Bidmead, Christopher H. (2006-05-09) [1985-03-25]. "Surviving Big Blue". Doctor Who. Which Computer?. Archived from the original on 2020-01-07. Retrieved 2020-01-07. […] Paul Bailey of Digital Research keenly promotes this approach; it is his company that is supplying ICL and others with Concurrent Dos-286. This chameleon operating system allows ICL and other 80286 manufacturers to build machines that will be able to cope with all the existing body of IBM-PC software -- and at the same time promise multi-tasking, windowing and true concurrency, three features that together allow a single micro to do several things at once. […] Although no firm announcements have been made, it seems certain that by the end of the year ACT will be offering a Concurrent CP/M 286 machine to fuel its drive into the corporate market. But by this time it will have to contend with IBM's own 80286 office micro, the PC/AT. […] IBM also have a software product in the offing that could pull the rug out from under the Concurrent contenders. Some 180K in size, TopView is a program for IBM PC's and AT's that beefs up the operating system to provide windowing facilities for existing 'well behaved' standard packages. […]
↑ High C Programmer's Guide - Version 1.2 for Concurrent DOS(PDF) (1ed.). Santa Cruz, CA, USA: MetaWare Incorporated. 1986 [1985-09-15]. Retrieved 2018-08-14. This is a guide to the operation of the High C compiler as implemented for the Concurrent DOS 286 1.2 or later operating system - hereafter abbreviated to just "Concurrent" per Digital Research custom - running on the Intel 80286 microprocessor and using the Intel Object-Module Format (OMF). The compiler generates code for any of the Intel 8086/88/186/188/286 family of microprocessors.
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