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This article is about the family of home computers. For other uses, see Amiga (disambiguation). The Amiga is a family of home/personal computers originally developed by Amiga Corporation as an advanced home entertainment and productivity machine. Development on the Amiga began in 1982 with Jay Miner (1932-1994) as the principal hardware designer. Commodore International introduced the machine to the market in 1985, after having bought Amiga Corp. The machine sported a custom chipset with advanced graphics and sound capabilities, and a sophisticated pre-emptive multitasking operating system, now known as AmigaOS. It ceased production in 1996, but efforts to revive the OS on newer hardware have continued to the present day. Based on the Motorola 68k series of 16-bit and 32-bit microprocessors, the Amiga provided a significant upgrade from 8-bit computers such as the Commodore 64, and the Amiga quickly grew in popularity among computer enthusiasts, especially in Europe. It also found a prominent role in the video production and show control business. Many considered it "ahead of its time" due to multimedia and multitasking capabilities that made it a less-expensive alternative to the Apple Macintosh, but allegedly suffered from poor marketing. History The Amiga was originally designed by a small company called Amiga Corporation as the ultimate video game machine. Before the machine was released into the market, the company was purchased by Commodore, and it was redesigned into a general-purpose computer. The first model, called the Amiga 1000, was released in 1985 as a successor to the Commodore 64 and a rival to the Atari ST. Commodore later released several new Amiga models, both for low-end gaming use and high-end productivity use. Throughout the 1980s, the Amiga's combination of hardware and operating system software offered immense power, but in the late nineties and early twenty-first century, other platforms, most of all the PC, reduced or eliminated this advantage. Hardware At the time of its introduction in 1985, the Amiga had what was a complex overall architecture, featuring coprocessors suited for audio and visual tasks. With its stereo sound, comparatively large color palette and brisk performance (due largely to the custom chipset) - not to mention its multitasking abilities - the Amiga was considered by some to be superior to all competing systems, despite competitors offering faster CPUs, higher resolution (though monochrome) graphics and (in some cases) built-in MIDI. The platform had three significant upgrades (not counting later non-Commodore technologies), with the Amiga 2000 in 1987, Amiga 3000 in 1990 and the Amiga 4000 in 1992. These upgrades improved the platform's graphical abilities, allowing for more colors and different display modes, and added expansion slots and ports. The best selling models however, were the much cheaper but still remarkably versatile console models, the Amiga 500 (based on the 68000 CPU and OCS chipset, see below) and the later Amiga 1200 (with a 68EC020 and AGA chipset). The platform also introduced other innovations. For example, the Amiga CDTV was the first computer to feature a CD-ROM drive as standard. The Amiga was also one of the first computers for which one could buy cheap accessories for sound sampling and video digitization. This means that not only can the Amiga produce computer-generated images and sound, but users can input "real" images and sound for editing, composition, and use in computer games. Central processing unit All Commodore Amiga models make use of Motorola CPUs based on the Motorola 68k architecture. Introduced by Motorola in 1979, the 68k CPU family has powered numerous computer and game systems, including the Atari ST, Apple Macintosh, Sega Mega Drive, and Sun Microsystems workstations and servers. In desktop style Amiga models the CPU was fitted on a daughterboard, called a CPU card. Low cost Amiga models came with CPUs either socketed or embedded on the motherboard. On all Amiga models the CPU could be upgraded through an expansion card or direct CPU replacement. CPU cards were provided by both Commodore and third party manufacturers. These cards often came with onboard memory slots and hard drive interfaces, alleviating those tasks from the base Amiga. The Amiga was not limited to solely the 68k CPU architecture; it was also possible to install a PPC coprocessor that could be used by PPC aware software and libraries. PPC accelerators are arguably self contained computers that only use the base Amiga for compatibility with chipset depended software and hardware. Custom chipset The Amiga's custom chipset, as the name implies, consists of a number of chips. There are three generations of chipsets used in the various Amiga models. The first is OCS, followed by ECS and finally AGA. What all these chipsets have in common is that they handle raster graphics, digital audio and communication between various peripherals (e.g. CPU, memory and floppy disks) in the Amiga. Graphics Earlier Amigas could display graphics in 32, 64 (EHB Mode) or even its full complement of 4096 (HAM Mode) colors long before the IBM PC compatible or the Apple Macintosh. Its revolutionary visual processor made it one of the first home computers used to do digital effects for a TV programme. Later models sporting the AGA chipset (A1200 and A4000) added 128, 256 and 262,000 color modes from a 24-bit (16.8 million) color palette. Sound The sound chip, named Paula, supports four sound channels (2 for the left speaker and 2 for the right) with 8 bit resolution for each channel and a 6 bit volume control. The analogue part of the chip is connected with a low-pass filter, filtering out the many high frequencies often created in computer systems. Trivia: Speech synthesis The original Amiga was launched with speech synthesis software, developed by Softvoice, Inc. * This could be broken into three main components: narrator.device, which could enunciate phonemes, translator.library which could translate English text to American English phonemes, and the SPEAK: handler, which command-line users could redirect output to, to have it spoken. In the original 1.x AmigaOS releases, a Say program demo was included with AmigaBASIC programming examples. For 2.0, Say became a standard utility program which did not need AmigaBASIC. Third party hardware Many expansion boards were produced for Amigas to improve the performance and capability of the hardware, such as memory expansions, SCSI controllers, CPU boards, graphics boards; famous third party hardware manufacturers were Great Valley Products (GVP) and Phase5. Later small manufacturers include Individual Computers. Other upgrades included genlocks, ethernet cards, modems, sound cards and samplers, video digitisers, USB cards, extra serial ports, and IDE controllers. The most popular upgrades were memory, SCSI controllers and CPU accelerator cards. These were sometimes combined into the one device, particularly on big box Amigas like the A2000, A3000 and A4000. Early CPU accelerator cards featured full 32bit CPUs of the 68000 family such as the 68020 and 68030, almost always with 32bit memory and usually with FPUs and MMUs or the facility to add them. Later designs featured the 68040 and 68060. Both CPUs featured integrated FPUs and MMUs. Many CPU accelerator cards also had integrated SCSI controllers. Phase5 designed the PowerUp boards (BlizzardPPC and CyberstormPPC) featuring both a 68k (a 68040 or 68060) and a PPC (603 or 604) CPU, which are able to run the two CPUs at the same time (and share the system memory). The PPC CPU on PowerUp boards is usually used as a coprocessor for heavy computations (a powerful CPU is needed to run for example MAME, but even decoding JPEG pictures and MP3 audio was considered heavy computation in those years). It is also possible to ignore the 68k CPU and run Linux on the PPC (project Linux APUS), but a PPC native Amiga OS was not available when the PPC boards first appeared. There were/are also available 24 bit graphics cards and video cards. Graphics cards are designed primarily for 2D artwork production, workstation use, and later, gaming. Video cards are designed for inputting and outputting video signals, and processing and manipulating video. Perhaps the most famous video card in the North American market was the Newtek Video Toaster. This was a powerful video effects board which turned the Amiga into an affordable video processing computer which found its way into many professional video environments. Due to its NTSC only design it did not find a market in countries that used the PAL standard, such as in Europe. In PAL countries the Opalvision card was popular, although less featured and supported than the Video Toaster. Various manufacturers started producing PCI busboards for the A1200 and A4000, allowing standard Amigas to use PCI cards such as Voodoo graphic cards, Soundblaster sound cards, 10/100 ethernet and TV tuners. PowerPC upgrades with Wide SCSI controllers, PCI busboards with ethernet, sound and 3D graphics cards, and towerised cases allowed the A1200 and A4000 to survive well into the late nineties as modern and competitive machines. Models and variants Classic Amiga models, from the 1000 to the 4000T, were produced from 1985 to 1996. Since then, no new generations of Classic Amigas have been produced. In addition, some companies released unofficial Amiga clones. AmigaOS 4 and beyond will run on both Amigas equipped with CyberstormPPC or BlizzardPPC accelerator boards, and on the PPC Teron series based AmigaOne computers. Emulating the Amiga Some modern-day "Amiga users" actually emulate the machine on modern hardware rather than running their software on the original hardware. AmigaOS
*NIX Commodore-Amiga produced Amiga Unix, informally known as Amix, based on AT&T SVR4. It supported the Amiga 2500 and Amiga 3000 and was included with the Amiga 3000UX. There are still enthusiasts running Amix but it was never supported on the later Amiga systems based on 68040 or 68060. Amix was sold primarily to college students. Among other unusual features of Amix was a hardware-accelerated windowing system which could scroll windows without copying data. Other, still maintained, operating systems are available for the classic Amiga platform, including Linux and NetBSD. Both require a CPU with MMU such as the 68020 with 68851 or full versions of the 68030, 68040 or 68060. There is a version of Linux for PPC accelerator cards. Debian and Yellow Dog Linux can run on the AmigaOne. There is an official, older version of OpenBSD. The last Amiga release is 3.2. The bootblock The very first production Amiga, the Amiga 1000, needs to load Kickstart from floppy disk into 256 kilobytes of RAM reserved for this purpose. Some games (notably Dragon's Lair) provide an alternative codebase to install, in order to use the extra 256 kilobytes of RAM for game material. However, subsequent Amigas hold Kickstart in a ROM chip. Kickstart selects a boot device (floppy or HD), loads the first two sectors of the disk or partition, and passes control to it. Some entertainment software contains a bootblock that loads the rest of the software from the disk and then pass control to it. The game or demo then summarily take control of memory and resources to suit itself, effectively disabling AmigaOS. The GUI can never be invoked. Therefore, some games and demos do not use the operating system at all. Alternatively, it can be said that they install their own custom operating system since any such program must install custom interrupt handlers and so on in order to be of any use. Such programs often had problems running on newer hardware. A floppy disk bootblock may alternatively contain code to load the dos.library (AmigaDOS) and then exit to it, invoking the GUI. Any such disk, no matter what the other contents of the disk, is known as a "DOS disk". The bootblock became an obvious target for virus writers. Custom bootblock loaders started to be created, which check for the presence of routines pointed by the reboot vectors or hooks in libraries before loading the dos.library, in order to detect viruses. Emulating other systems The Amiga is able to emulate other computer platforms which were in its same price range, or even far more expensive most notably the IBM PC, the Apple Macintosh and the Atari ST. There are also emulators available for many 8 bit systems such as the Commodore 64, Apple II and even the TRS-80. MAME (the arcade machine emulator) is also available for Amigas with PPC accelerator card upgrades. Amiga software The Amiga was a primary target for productivity and game development during the late 1980s and early 1990s. Software was often developed for the Amiga and the Atari ST simultaneously, since the ST shared a similar architecture. All Amiga software is 32 bit on all Amiga models including the original 1985 A1000 and the economy A500. All Amiga CPUs contain 16 general purpose 32-bit registers. All Amiga CPUs and software may easily move 32 bits of data from point A to point B in a single machine instruction. 32 bit addressing limited the Amiga 1200 to a maximum of 4096 MB of directly addressable ram. Unfortunately the AmigaOS only truly supports 2048 MB, and older Amigas such as Amiga 500 only have 24 bits of addressing, so they can only directly address 16 MB. Much of the freely available software was available on Aminet. Until around 1996, Aminet was the largest public archive of software for any platform. Amiga community When Commodore went bankrupt in 1994, there was still a very active Amiga community, and it continued to support the platform long after mainstream commercial vendors abandoned it. The most popular Amiga magazine, Amiga Format, continued to publish editions until 2000, some six years after Commodore filed for bankruptcy. One reason for this loyalty is the multiple strengths of the machine: it has a relatively compact, efficient, multitasking OS, it is relatively easy to program for, software has easy access to the hardware (the base hardware was fixed so software could be coded specifically to the hardware), there is wealth of software, and it was an affordable multimedia machine. The Amiga also allows an unusual degree of control over its environment and functions which makes it both highly configurable and remarkably versatile, so that it can be tailored to a user's unique needs and preferences, much more so in many ways than a modern PC. However as time wore on, the hardware was overtaken and as the PC improved in software and hardware the Amiga started to look dated. Despite this, its solid user base continues to produce software and get as much as they possibly can out of the machine. Amiga users manage to squeeze every drop of performance and capability out of the machines, with software and hardware expansions to enhance its capabilities. Even today (2nd qtr. 2006) there is enough demand for expansion hardware to keep some small scale manufacturers in business. After Commodore went bankrupt The bankruptcy of Commodore in 1994 severely stunted the Amiga's growth. Production was halted briefly, until it was restarted for a short time under Escom's Amiga Technologies. Though the machines had been upgraded and had plentiful hardware and software support, the lack of new Amigas meant that vendors sooner or later moved on. Most of the 'leading edge' technology hobbyists and productivity market moved to PC architecture. Due to the fierce loyalty of some Amiga fans, the 'scene' continued, many years even after the last original Amiga was sold. Inevitably, though, the PC eventually became the undisputed leading home computing technology, and the console wars also left the CD32 for dead. The rights to the Amiga platform were successively sold to Escom and later Gateway 2000, but Escom almost immediately went bankrupt itself (due to non-Amiga related problems) and Gateway merely vacillated over what to do with its new acquisition. Finally, an entirely new company called Amiga, Inc. (no relation to the original Amiga Corporation) was founded to manage the Amiga product line. Even though Amiga, Inc. has paid considerably more attention to the Amiga product line than Escom or Gateway 2000, because of the extremely small demand in the mainstream market and limited funds, development has been slow and sales poor. In 2002, Eyetech in cooperation with Amiga Inc, began selling a small number of AmigaOnes. The "AmigaOne SE" was based on Mai Logic's Teron CX motherboard from 2001 based on the POP (PowerPC Open Platform) design, and development to adapt AmigaOS 4 to this hardware began. The AmigaOne SE was succeeded by AmigaOne XE, which was based on the Teron PX, a newer design with a replaceable CPU module which came in G3 and G4 flavours. In 2004, Eyetech began selling the Micro-A1, based on the Teron Mini, a mini-ITX model with a 750GX G3 CPU. The older Amigas are sometimes referred to as "Classic Amigas" to avoid possible confusion with the AmigaOnes. AmigaOnes are not currently being produced or sold. It is not known whether more will be made. AmigaOS 4 is still under development, and reports are that it is quite stable and usable. It is hoped that it may be ported to other hardware, possibly another evaluation board, the Pegasos or some kind of Cell based device. AmigaOS clones Following Commodore's bankruptcy, two main clones of AmigaOS were developed: MorphOS, which runs on Pegasos machines, and the free software AROS project. Trivia See also | |||||||||
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