Phar Lap (company)
Encyclopedia
Phar Lap was a software company specializing in software development tools for DOS
operating system
s. They were most noted for their software allowing developers to access memory beyond the 640 KiB limit of DOS (DOS extender
s) and were an author of the VCPI standard.
Phar Lap Software, Inc. was founded in April 1986 by Richard M. Smith, Robert Moote, and John M. Benfatto. Their first major success, 386|DOS-Extender, a 32-bit
protected mode
development tool, was released in November 1986.
Phar Lap’s product line was expanded to include 386|VMM, a virtual memory
add-in driver
, LinkLoc, a linker-locator for embedded development; cross tools for embedded development; and 286|DOS-Extender, a DOS extender that emulated an OS/2
environment, complete with the OS/2 API and protected mode, in contrast with Microsoft's OS/2 API emulation, which ran OS/2 applications in real mode
and only supported a subset of the OS/2 API, called the Family API. Therefore it was often bound with existing OS/2 applications, replacing Microsoft's OS/2 API emulation for those applications that needed access to extended memory in DOS. Later on the TNT DOS extender
was created, which was a version of 386|DOS-Extender that emulated the Win32 environment, complete with flat address space and threading. Again this DOS extender was often bound to existing Win32 applications. Unfortunately, MASM 6.1 and the 16-bit version of the Visual C++
1.0 compiler were Win32 applications written for a beta version of Windows NT
that was bound with the TNT DOS Extender, which means it could not run on the final version of Windows NT until Beta2Fix.exe was run, which replaced all references to NTDLL.DLL with BETA2.DLL. This was fixed in MASM 6.11 and Visual C++ 1.5. Much later the HX DOS Extender
product was created that also emulates the Win32 environment on DOS, has been under heavy development from 2004 up to now (2007), and achieved a much better compatibility than any other attempt before.
Phar Lap developed the Virtual Control Program Interface
(VCPI) specification in cooperation with Quarterdeck Office Systems
, who produced the DesqView
task-switching software. Phar Lap was also a member of the 12-firm committee that designed the DOS Protected Mode Interface
(DPMI). VCPI and DPMI are industry standards allowing DOS extenders to co-exist with expanded memory
(EMS) emulators and multi-tasking environments.
Phar Lap received several major PC industry awards for VCPI, 386|DOS-Extender, and 286|DOS-Extender.
Phar Lap was named for the great Trans-Tasman
race horse Phar Lap
. The horse was rather inelegant in appearance, but performed spectacularly, setting everyone on their heels until he died a mysterious death.
There was no mystery when the market for DOS extenders died, however; they were not needed by 32-bit Windows applications
which could directly address all the memory the computer hardware
would support.
Phar Lap is now part of IntervalZero
, formerly Ardence
, which produces, among other products, the Phar Lap ETS real-time operating system
, used for instance on LabVIEW
real-time targets.
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...
operating system
Operating system
An operating system is a set of programs that manage computer hardware resources and provide common services for application software. The operating system is the most important type of system software in a computer system...
s. They were most noted for their software allowing developers to access memory beyond the 640 KiB limit of DOS (DOS extender
DOS extender
A DOS extender is a computer software program which enables software to run under a protected mode environment even though the host operating system is only capable of operating in real mode....
s) and were an author of the VCPI standard.
Phar Lap Software, Inc. was founded in April 1986 by Richard M. Smith, Robert Moote, and John M. Benfatto. Their first major success, 386|DOS-Extender, a 32-bit
32-bit
The range of integer values that can be stored in 32 bits is 0 through 4,294,967,295. Hence, a processor with 32-bit memory addresses can directly access 4 GB of byte-addressable memory....
protected mode
Protected mode
In computing, protected mode, also called protected virtual address mode, is an operational mode of x86-compatible central processing units...
development tool, was released in November 1986.
Phar Lap’s product line was expanded to include 386|VMM, a virtual memory
Virtual memory
In computing, virtual memory is a memory management technique developed for multitasking kernels. This technique virtualizes a computer architecture's various forms of computer data storage , allowing a program to be designed as though there is only one kind of memory, "virtual" memory, which...
add-in driver
Device driver
In computing, a device driver or software driver is a computer program allowing higher-level computer programs to interact with a hardware device....
, LinkLoc, a linker-locator for embedded development; cross tools for embedded development; and 286|DOS-Extender, a DOS extender that emulated an OS/2
OS/2
OS/2 is a computer operating system, initially created by Microsoft and IBM, then later developed by IBM exclusively. The name stands for "Operating System/2," because it was introduced as part of the same generation change release as IBM's "Personal System/2 " line of second-generation personal...
environment, complete with the OS/2 API and protected mode, in contrast with Microsoft's OS/2 API emulation, which ran OS/2 applications in real mode
Real mode
Real mode, also called real address mode, is an operating mode of 80286 and later x86-compatible CPUs. Real mode is characterized by a 20 bit segmented memory address space and unlimited direct software access to all memory, I/O addresses and peripheral hardware...
and only supported a subset of the OS/2 API, called the Family API. Therefore it was often bound with existing OS/2 applications, replacing Microsoft's OS/2 API emulation for those applications that needed access to extended memory in DOS. Later on the TNT DOS extender
DOS extender
A DOS extender is a computer software program which enables software to run under a protected mode environment even though the host operating system is only capable of operating in real mode....
was created, which was a version of 386|DOS-Extender that emulated the Win32 environment, complete with flat address space and threading. Again this DOS extender was often bound to existing Win32 applications. Unfortunately, MASM 6.1 and the 16-bit version of the Visual C++
Visual C++
Microsoft Visual C++ is a commercial , integrated development environment product from Microsoft for the C, C++, and C++/CLI programming languages...
1.0 compiler were Win32 applications written for a beta version of Windows NT
Windows NT
Windows NT is a family of operating systems produced by Microsoft, the first version of which was released in July 1993. It was a powerful high-level-language-based, processor-independent, multiprocessing, multiuser operating system with features comparable to Unix. It was intended to complement...
that was bound with the TNT DOS Extender, which means it could not run on the final version of Windows NT until Beta2Fix.exe was run, which replaced all references to NTDLL.DLL with BETA2.DLL. This was fixed in MASM 6.11 and Visual C++ 1.5. Much later the HX DOS Extender
HX DOS Extender
The HX DOS Extender is a free DOS extender with built-in Win32 PE file format support. Usually the purpose of a DOS extender is to make protected mode features, especially large memory and 32-bit addressing, available for DOS applications. HX fully supports this goal, but goes some steps further...
product was created that also emulates the Win32 environment on DOS, has been under heavy development from 2004 up to now (2007), and achieved a much better compatibility than any other attempt before.
Phar Lap developed the Virtual Control Program Interface
Virtual Control Program Interface
In computing, the Virtual Control Program Interface is a specification published in 1989 by Phar Lap Software that allows a DOS program to run in protected mode, granting access to many features of the processor not available in real mode...
(VCPI) specification in cooperation with Quarterdeck Office Systems
Quarterdeck Office Systems
Quarterdeck Office Systems, later Quarterdeck Corporation , was an American computer software company. It was founded by Therese Myers and Gary Pope in 1981and incorporated in 1982...
, who produced the DesqView
DESQview
DESQview was a text mode multitasking program developed by Quarterdeck Office Systems which enjoyed modest popularity in the late 1980s and early 1990s...
task-switching software. Phar Lap was also a member of the 12-firm committee that designed the DOS Protected Mode Interface
DOS Protected Mode Interface
In computing, the DOS Protected Mode Interface is a specification introduced in 1989 which allows a DOS program to run in protected mode, giving access to many features of the processor not available in real mode...
(DPMI). VCPI and DPMI are industry standards allowing DOS extenders to co-exist with expanded memory
Expanded memory
In DOS memory management, expanded memory is a system of bank switching introduced April 24, 1985 that provided additional memory to DOS programs beyond the limit of conventional memory. Expanded memory uses parts of the address space normally dedicated to communication with peripherals for program...
(EMS) emulators and multi-tasking environments.
Phar Lap received several major PC industry awards for VCPI, 386|DOS-Extender, and 286|DOS-Extender.
Phar Lap was named for the great Trans-Tasman
Trans-Tasman
Trans-Tasman is an adjective used primarily in Australia and New Zealand, which signifies an interrelationship between both countries. Its name originates from the Tasman Sea which lies between the two countries...
race horse Phar Lap
Phar Lap
Phar Lap was a champion Thoroughbred racehorse whose achievements captured the public's imagination during the early years of the Great Depression. Foaled in New Zealand, he was trained and raced in Australia. Phar Lap dominated Australian racing during a distinguished career, winning a Melbourne...
. The horse was rather inelegant in appearance, but performed spectacularly, setting everyone on their heels until he died a mysterious death.
There was no mystery when the market for DOS extenders died, however; they were not needed by 32-bit Windows applications
Windows API
The Windows API, informally WinAPI, is Microsoft's core set of application programming interfaces available in the Microsoft Windows operating systems. It was formerly called the Win32 API; however, the name "Windows API" more accurately reflects its roots in 16-bit Windows and its support on...
which could directly address all the memory the computer hardware
Hardware
Hardware is a general term for equipment such as keys, locks, hinges, latches, handles, wire, chains, plumbing supplies, tools, utensils, cutlery and machine parts. Household hardware is typically sold in hardware stores....
would support.
Phar Lap is now part of IntervalZero
IntervalZero
IntervalZero, Inc. - Formerly Ardence, a Citrix Company - develops embedded software products that deliver real-time control capability for the embedded technology market. Founded in July 2008 by a group of former Ardence executives, IntervalZero is headed by CEO Jeffrey D...
, formerly Ardence
Ardence
Ardence, a Citrix Company, is a technology company headquartered in Waltham, Massachusetts with representatives in Washington, D.C.; Virginia Beach, VA; Chicago, IL; Denton, TX; and Europe, Middle East, Africa and India....
, which produces, among other products, the Phar Lap ETS real-time operating system
Real-time operating system
A real-time operating system is an operating system intended to serve real-time application requests.A key characteristic of a RTOS is the level of its consistency concerning the amount of time it takes to accept and complete an application's task; the variability is jitter...
, used for instance on LabVIEW
LabVIEW
LabVIEW is a system design platform and development environment for a visual programming language from National Instruments. LabVIEW provides engineers and scientists with the tools needed to create and deploy measurement and control systems.The graphical language is named "G"...
real-time targets.