FlexOS
Encyclopedia
FlexOS was a modular real-time multi-user multi-tasking operating system (RTOS) designed for computer-integrated manufacturing, laboratory, retail and financial markets. It was developed by Digital Research
's Flexible Automation Business Unit in Monterey
, California since 1986 and was marketed since January 1987 as a derivation of Digital Research's Concurrent DOS 286 multiuser multitasking operating system.
The original protected mode
FlexOS 286 version 1.0 was designed for host machines equipped with 286 CPUs, and with adaptions for NEC V60
, NEC V70 and Motorola
68000 processors planned. FlexOS 286 executables using the system's native INT 220 application program interface had the file extension .286. A CP/M API front end (FE) was available as well. (A file extension of .68K was reserved for FlexOS 68K, presumably derived from Concurrent DOS 68K as of 1986.)
In May 1987, FlexOS version 1.31 was released for 80286 machines. The developer version required a IBM PC/AT compatible machine with 640 KB of conventional
and 512 KB 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, mouses 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 would execute a CONFIG.BAT startup batchjob instead of the common AUTOEXEC.BAT
.
FlexOS' optional DOS emulator provided limited PC DOS 2.1 compatibility for DOS .COM and .EXE programs. Certain restrictions applied 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. These problems had already caused delays in the delivery of Concurrent DOS 286 earlier.
The system optionally supported a multitasking GEM
VDI for graphical applications.
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).
FlexOS 286 and FlexOS 386 versions 2.0 were registered on 3 July 1989.
Novell
bought Digital Research in July 1991.
X/GEM for FlexOS release 1.0 (aka X/GEM FlexOS 286 and 386) and FlexNet were registered on 21 December 1992.
FlexOS was used as the primary test platform for the new Novell Embedded Systems Technology
(NEST).
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 in July 1994. 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. FlexOS version 2.33 was current as of May 1998 and with FlexOS 2.34 to be released soonafter 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 1999.
originally chosed DR Concurrent DOS 286 as the basis of their IBM 4680 computer for IBM Plant System products and Point-of-Sale terminals in 1986. The last release of the IBM 4680 OS has been version 4, before it was replaced by IBM 4690 version 1.
version 1, to be pre-released on 24 September 1993 and generally made available from 25 March 1994. 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. Further, it removed limits on the number of applications running concurrently due to its more efficient use of KOSPOOL.
IBM continues to maintain their 4690 OS up to the present, with the most recent version in April 2010 being IBM 4690 OS version 6.2.
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.
Digital Research
Digital Research, Inc. was the company created by Dr. Gary Kildall to market and develop his CP/M operating system and related products. It was the first large software company in the microcomputer world...
's Flexible Automation Business Unit in Monterey
Monterey, California
The City of Monterey in Monterey County is located on Monterey Bay along the Pacific coast in Central California. Monterey lies at an elevation of 26 feet above sea level. As of the 2010 census, the city population was 27,810. Monterey is of historical importance because it was the capital of...
, California since 1986 and was marketed since January 1987 as a derivation of Digital Research's Concurrent DOS 286 multiuser multitasking operating system.
Overview
FlexOS was re-written in C for higher portability across hardware platforms, and it featured very low interrupt latency and fast context switching.The original protected mode
Protected mode
In computing, protected mode, also called protected virtual address mode, is an operational mode of x86-compatible central processing units...
FlexOS 286 version 1.0 was designed for host machines equipped with 286 CPUs, and with adaptions for NEC V60
NEC V60
The NEC V60 was a CISC processor manufactured by NEC introduced in the late 1980s. It had a 32-bit internal bus and a 16-bit external bus with a 24-bit address bus. A relatively obscure design, it was a radical departure from NEC's previous V-series CPUs , most of which were based on the Intel x86...
, NEC V70 and Motorola
Motorola
Motorola, Inc. was an American multinational telecommunications company based in Schaumburg, Illinois, which was eventually divided into two independent public companies, Motorola Mobility and Motorola Solutions on January 4, 2011, after losing $4.3 billion from 2007 to 2009...
68000 processors planned. FlexOS 286 executables using the system's native INT 220 application program interface had the file extension .286. A CP/M API front end (FE) was available as well. (A file extension of .68K was reserved for FlexOS 68K, presumably derived from Concurrent DOS 68K as of 1986.)
In May 1987, FlexOS version 1.31 was released for 80286 machines. The developer version required a IBM PC/AT compatible machine with 640 KB of conventional
Conventional memory
In DOS memory management, conventional memory, also called base memory, is the first 640 kilobytes of the memory on IBM PC or compatible systems. It is the read-write memory usable by the operating system and application programs...
and 512 KB of extended memory
Extended memory
In DOS memory management, extended memory refers to memory above the first megabyte of address space in an IBM PC or compatible with an 80286 or later processor. The term is mainly used under the DOS and Windows operating systems...
, 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, mouses 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
CONFIG.SYS
CONFIG.SYS is the primary configuration file for the DOS, OS/2 as well as similar operating systems. It is a special file that contains setup or configuration instructions for the computer system.- Usage :...
configuration file under DOS
DOS
DOS, short for "Disk Operating System", is an acronym for several closely related operating systems that dominated the IBM PC compatible market between 1981 and 1995, or until about 2000 if one includes the partially DOS-based Microsoft Windows versions 95, 98, and Millennium Edition.Related...
), and its shell would execute a CONFIG.BAT startup batchjob instead of the common AUTOEXEC.BAT
AUTOEXEC.BAT
AUTOEXEC.BAT is a system file found originally on DOS-type operating systems. It is a plain-text batch file that is located in the root directory of the boot device...
.
FlexOS' optional DOS emulator provided limited PC DOS 2.1 compatibility for DOS .COM and .EXE programs. Certain restrictions applied 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. These problems had already caused delays in the delivery of Concurrent DOS 286 earlier.
The system optionally supported a multitasking GEM
Graphical Environment Manager
GEM was a windowing system created by Digital Research, Inc. for use with the CP/M operating system on the Intel 8088 and Motorola 68000 microprocessors...
VDI for graphical applications.
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).
FlexOS 286 and FlexOS 386 versions 2.0 were registered on 3 July 1989.
Novell
Novell
Novell, Inc. is a multinational software and services company. It is a wholly owned subsidiary of The Attachmate Group. It specializes in network operating systems, such as Novell NetWare; systems management solutions, such as Novell ZENworks; and collaboration solutions, such as Novell Groupwise...
bought Digital Research in July 1991.
X/GEM for FlexOS release 1.0 (aka X/GEM FlexOS 286 and 386) and FlexNet were registered on 21 December 1992.
FlexOS was used as the primary test platform for the new Novell Embedded Systems Technology
Novell Embedded Systems Technology
Novell Embedded Systems Technology, or NEST, was a series of APIs, data formats and network protocol stacks written in a highly portable fashion intended to be used in embedded systems. The idea was to allow various small devices to access Novell NetWare services, provide such services, or use...
(NEST).
When Novell decided to abandon further development of the various Digital Research operating systems such as Multiuser DOS
Multiuser DOS
Multiuser DOS is a soft real-time multi-user multi-tasking operating system for IBM PC-compatible microcomputers.An evolution of the older Concurrent CP/M-86 and Concurrent DOS operating systems, it was originally developed by Digital Research and later further developed by Novell...
(a successor to Concurrent DOS) and Novell DOS (a successor to DR DOS), they sold FlexOS off to the Santa Clara
Santa Clara, California
Santa Clara , founded in 1777 and incorporated in 1852, is a city in Santa Clara County, in the U.S. state of California. The city is the site of the eighth of 21 California missions, Mission Santa Clara de Asís, and was named after the mission. The Mission and Mission Gardens are located on the...
, California-based Integrated Systems, Inc. (ISI) for in July 1994. The deal comprised a direct payment of half this sum as well as shares representing 2% of the company. The company already had pSOS+
PSOS
pSOS is a real time operating system , created in about 1982 by Alfred Chao, and developed/marketed for the first part of its life by his company Software Components Group...
, another modular real-time multitasking operating system for embedded systems, but they continued to maintain FlexOS as well. FlexOS version 2.33 was current as of May 1998 and with FlexOS 2.34 to be released soonafter 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
Wind River Systems
Wind River Systems, Inc. is a company providing embedded systems, development tools for embedded systems, middleware, and other types of software. The company was founded in Berkeley, California in 1981 by Jerry Fiddler and David Wilner. On June 4, 2009, Wind River announced that Intel had bought...
in 1999.
IBM 4680 OS
Named IBM 4680 OS version 1, IBMIBM
International Business Machines Corporation or IBM is an American multinational technology and consulting corporation headquartered in Armonk, New York, United States. IBM manufactures and sells computer hardware and software, and it offers infrastructure, hosting and consulting services in areas...
originally chosed DR Concurrent DOS 286 as the basis of their IBM 4680 computer for IBM Plant System products and Point-of-Sale terminals in 1986. The last release of the IBM 4680 OS has been version 4, before it was replaced by IBM 4690 version 1.
IBM 4690 OS
In July 1993, IBM announced the adoption of FlexOS version 2.32 as the basis of their IBM 4690 OSIBM 4690 OS
IBM 4690 Operating System, sometimes shortened to 4690 OS or 4690, is IBM's specially designed Point of Sale operating system. 4690 is widely used by IBM's retail customers to drive retail systems running their own applications as well as IBM's Application Client Server Environment , Supermarket...
version 1, to be pre-released on 24 September 1993 and generally made available from 25 March 1994. 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. Further, it removed limits on the number of applications running concurrently due to its more efficient use of KOSPOOL.
IBM continues to maintain their 4690 OS up to the present, with the most recent version in April 2010 being IBM 4690 OS version 6.2.
Siemens S5-DOS/MT
SiemensSiemens AG
Siemens AG is a German multinational conglomerate company headquartered in Munich, Germany. It is the largest Europe-based electronics and electrical engineering company....
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
Btrieve
Btrieve is a transactional database software product. It is based on Indexed Sequential Access Method , which is a way of storing data for fast retrieval...
, whereas the smaller S5-DOS system, also present on these systems, is a variant of Digital Research's Personal CP/M-86.
See also
- Concurrent DOS 286
- GEMGraphical Environment ManagerGEM was a windowing system created by Digital Research, Inc. for use with the CP/M operating system on the Intel 8088 and Motorola 68000 microprocessors...
- IBM 4680 OS
- IBM 4683IBM 4683The IBM 4683 was IBM's first PC based point of sale system. It was introduced in 1985. The system consists of a PC-based controller and thin client based POS workstations, typically with a token ring network. The system requires an IBM AS/400 server to be in the network. The 4683 is still used...
- IBM 4690 OSIBM 4690 OSIBM 4690 Operating System, sometimes shortened to 4690 OS or 4690, is IBM's specially designed Point of Sale operating system. 4690 is widely used by IBM's retail customers to drive retail systems running their own applications as well as IBM's Application Client Server Environment , Supermarket...
- IBM 4693
- IBM 4694IBM 4694The IBM 4694 was IBM's PC based point of sale system, successor to the IBM 4683 and IBM 4693. Introduced in 1991, the 4694 became a flagship model for the company's SurePOS system. The system consists of a PC-based controller , and POS workstations—typically an IBM keyboard and monitor, or touch...
- IBM 4695
- pSOSPSOSpSOS is a real time operating system , created in about 1982 by Alfred Chao, and developed/marketed for the first part of its life by his company Software Components Group...