Apple II processor cards (or co-processor cards) were special cards that could be used to allow the Apple II to use different processors on the (otherwise) same computer hardware. This allowed other operating systems to run on the Apple II.
Here are some processors that were available on coprocessor cards for the Apple II:
The Apple II series of microcomputers was initially designed by Steve Wozniak, manufactured by Apple Computer, and launched in 1977 with the Apple II model that gave the series its name. It was followed by the Apple II Plus, Apple IIe, Apple IIc, and Apple IIc Plus, with the 1983 IIe being the most popular. The name is trademarked with square brackets as Apple ][, then, beginning with the IIe, as Apple //. In terms of ease of use, features, and expandability, the Apple II was a major advancement over its predecessor, the Apple I, a limited-production bare circuit board computer for electronics hobbyists.
The Motorola 6809 ("sixty-eight-oh-nine") is an 8-bit microprocessor with some 16-bit features. It was designed by Motorola's Terry Ritter and Joel Boney and introduced in 1978. Although source compatible with the earlier Motorola 6800, the 6809 offered significant improvements over it and 8-bit contemporaries like the MOS Technology 6502, including a hardware multiplication instruction, 16-bit arithmetic, system and user stack registers allowing re-entrant code, improved interrupts, position-independent code, and an orthogonal instruction set architecture with a comprehensive set of addressing modes.
CP/M, originally standing for Control Program/Monitor and later Control Program for Microcomputers, is a mass-market operating system created in 1974 for Intel 8080/85-based microcomputers by Gary Kildall of Digital Research, Inc. CP/M is a disk operating system and its purpose is to organize files on a magnetic storage medium, and to load and run programs stored on a disk. Initially confined to single-tasking on 8-bit processors and no more than 64 kilobytes of memory, later versions of CP/M added multi-user variations and were migrated to 16-bit processors.
Wintel is the partnership of Microsoft Windows and Intel producing personal computers using Intel x86-compatible processors running Microsoft Windows.
Microsoft BASIC is the foundation software product of the Microsoft company and evolved into a line of BASIC interpreters and compiler(s) adapted for many different microcomputers. It first appeared in 1975 as Altair BASIC, which was the first version of BASIC published by Microsoft as well as the first high-level programming language available for the Altair 8800 microcomputer.
A coprocessor is a computer processor used to supplement the functions of the primary processor. Operations performed by the coprocessor may be floating-point arithmetic, graphics, signal processing, string processing, cryptography or I/O interfacing with peripheral devices. By offloading processor-intensive tasks from the main processor, coprocessors can accelerate system performance. Coprocessors allow a line of computers to be customized, so that customers who do not need the extra performance do not need to pay for it.
The Tandy 2000 is a personal computer introduced by Radio Shack in September 1983 based on the 8 MHz Intel 80186 microprocessor running MS-DOS. By comparison, the IBM PC XT used the older 4.77 MHz Intel 8088 processor, and the IBM PC/AT would later use the newer 6 MHz Intel 80286. Due to the 16-bit data bus and more efficient instruction decoding of the 80186, the Tandy 2000 ran significantly faster than other PC compatibles, and slightly faster than the PC AT. The Tandy 2000 was the company's first computer built around an Intel x86 series microprocessor; previous models used the Zilog Z80 and Motorola 6809 CPUs.
The Rainbow 100 is a microcomputer introduced by Digital Equipment Corporation (DEC) in 1982. This desktop unit had a monitor similar to the VT220 and a dual-CPU box with both 4 MHz Zilog Z80 and 4.81 MHz Intel 8088 CPUs. The Rainbow 100 was a triple-use machine: VT100 mode, 8-bit CP/M mode, and CP/M-86 or MS-DOS mode using the 8088. It ultimately failed to in the marketplace which became dominated by the simpler IBM PC and its clones which established the industry standard as compatibility with CP/M became less important than IBM PC compatibility. Writer David Ahl called it a disastrous foray into the personal computer market. The Rainbow was launched along with the similarly packaged DEC Professional and DECmate II which were also not successful. The failure of DEC to gain a significant foothold in the high-volume PC market would be the beginning of the end of the computer hardware industry in New England, as nearly all computer companies located there were focused on minicomputers for large organizations, from DEC to Data General, Wang, Prime, Computervision, Honeywell, and Symbolics Inc.
A/ROSE is a small embedded operating system that runs on Apple Computer's "Macintosh Coprocessor Platform", an expansion card for the Macintosh.
The Amiga computer can be used to emulate several other computer platforms, including legacy platforms such as the Commodore 64, and its contemporary rivals such as the IBM PC and the Macintosh.
The Mac286 was an Intel 80286-based MS-DOS coprocessor expansion card for one of Apple Computer's first expandable Macintosh computers, the 1987 Macintosh II. It was developed by Phoenix Technologies under contract to Apple Computer and sold by AST Research in an effort to close the gap between the Macintosh and IBM PC computing worlds. AST also introduced the related Mac86 card for the Macintosh SE.
The Apple II Plus is the second model of the Apple II series of personal computers produced by Apple Computer. It was sold from June 1979 to December 1982. Approximately 380,000 II Pluses were sold during its four years in production before being replaced by the Apple IIe in January 1983.
The Z-80 SoftCard is a plug-in Apple II processor card developed by Microsoft to turn the computer into a CP/M system based upon the Zilog Z80 central processing unit (CPU). Becoming the most popular CP/M platform and Microsoft's top revenue source for 1980, it was eventually renamed the Microsoft SoftCard, and was succeeded by Microsoft's Premium Softcard IIe for the Apple IIe.
Following the introduction of the IBM Personal Computer, or IBM PC, many other personal computer architectures became extinct within just a few years. It led to a wave of IBM PC compatible systems being released.
DOS is a family of disk-based operating systems for IBM PC compatible computers. The DOS family primarily consists of IBM PC DOS and a rebranded version, Microsoft's MS-DOS, both of which were introduced in 1981. Later compatible systems from other manufacturers include DR-DOS (1988), ROM-DOS (1989), PTS-DOS (1993), and FreeDOS (1998). MS-DOS dominated the IBM PC compatible market between 1981 and 1995.
The ICL DRS was a range of departmental computers from International Computers Limited (ICL). Standing originally for Distributed Resource System, the full name was later dropped in favour of the abbreviation.
ALF Products Inc., or ALF, was a Colorado company primarily known for its computer-controlled music synthesizers and floppy disk supplies and duplicators.
The Dimension 68000 is a microcomputer introduced by the Micro Craft Corporation in 1983 that sought to emulate the Apple II, the IBM PC, and various CP/M-centric computers through a family of coprocessor expansion cards and emulation software. The Dimension 68000 can also run as a standalone computer based on the Motorola 68000 from which it gets its namesake. The computer is mostly the brainchild of Mike Carpenter, a former executive of a scientific instrument manufacturer who incorporated Micro Craft in Dallas, Texas, to develop the Dimension 68000. It had a market lifespan of three years and received mixed, mostly positive, reception from the technology press. Criticism was leveled at the $6,250 price tag for the computer with the full deck of coprocessor cards, as well as the extent of the emulation power of those cards.