Amiga

Amiga

The 1987 Amiga 500 was the bestselling model.
Manufacturer	Commodore International
Product family	Amiga
Type	Personal computer Game console (CD32)
Release date	July 23, 1985; 38 years ago (1985-07-23) (Amiga 1000)
Introductory price	Amiga 1000: US$1,295 (equivalent to $3,670 in 2023) Monitor: US$300 (equivalent to $850 in 2023)
Discontinued	1996 (Amiga 1200 & 4000T)
Units sold	4.85 million[1]
Operating system	AmigaOS on Kickstart
CPU	Motorola 680x0 @ ≈7+ MHz
Memory	256 KB and up, expandable
Predecessor	Commodore 128 Commodore 64

Amiga is a family of personal computers introduced by Commodore in 1985. The original model is one of a number of mid-1980s computers with 16- or 16/32-bit processors, 256 KB or more of RAM, mouse-based GUIs, and significantly improved graphics and audio compared to previous 8-bit systems. These systems include the Atari ST—released earlier the same year—as well as the Macintosh and Acorn Archimedes. Based on the Motorola 68000 microprocessor, the Amiga differs from its contemporaries through the inclusion of custom hardware to accelerate graphics and sound, including sprites and a blitter, and a pre-emptive multitasking operating system called AmigaOS.

The Amiga 1000 was released in July 1985, but production problems kept it from becoming widely available until early 1986. The best-selling model, the Amiga 500, was introduced in 1987 along with the more expandable Amiga 2000. The Amiga 3000 was introduced in 1990, followed by the Amiga 500 Plus, and Amiga 600 in March 1992. Finally, the Amiga 1200 and Amiga 4000 were released in late 1992. The Amiga line sold an estimated 4.85 million units.

Although early advertisements cast the computer as an all-purpose business machine,^{[2][3][4][5][6][7]} especially when outfitted with the Sidecar IBM PC compatibility add-on, the Amiga was most commercially successful as a home computer, with a wide range of games and creative software. It also found a niche in video production with the Video Toaster hardware and software, and Amiga's audio hardware made it a popular platform for music tracker software. The processor and memory capacity enabled 3D rendering packages, including LightWave 3D, Imagine, and Traces, a predecessor to Blender.

Poor marketing and the failure of later models to repeat the technological advances of the first systems resulted in Commodore quickly losing market share to the rapidly dropping prices of IBM PC compatibles, which gained 256 color graphics in 1987,^[8] as well as the fourth generation of video game consoles.

Commodore ultimately went bankrupt in April 1994 after a version of the Amiga packaged as a game console, the Amiga CD32, failed in the marketplace. Since the demise of Commodore, various groups have marketed successors to the original Amiga line, including Genesi, Eyetech, ACube Systems Srl and A-EON Technology. AmigaOS has influenced replacements, clones, and compatible systems such as MorphOS and AROS. Currently Belgian company Hyperion Entertainment maintains and develops AmigaOS 4, which is an official and direct descendant of AmigaOS 3.1 – the last system made by Commodore for the original Amiga Computers.

History[edit]

Concept and early development[edit]

Jay Miner joined Atari, Inc. in the 1970s to develop custom integrated circuits, and led development of the Atari Video Computer System's TIA.^[9] When complete, the team began developing a much more sophisticated set of chips, CTIA, ANTIC and POKEY, that formed the basis of the Atari 8-bit computers.^[10]

With the 8-bit line's launch in 1979, the team once again started looking at a next generation chipset. Nolan Bushnell had sold the company to Warner Communications in 1978, and the new management was much more interested in the existing lines than development of new products that might cut into their sales. Miner wanted to start work with the new Motorola 68000, but management was only interested in another 6502 based system. Miner left the company, and, for a time, the industry.^[10]

In 1979, Larry Kaplan left Atari and founded Activision. In 1982, Kaplan was approached by a number of investors who wanted to develop a new game platform. Kaplan hired Miner to run the hardware side of the newly formed company, "Hi-Toro". The system was code-named "Lorraine" in keeping with Miner's policy of giving systems female names, in this case the company president's wife, Lorraine Morse.^[11] When Kaplan left the company late in 1982, Miner was promoted to head engineer^[10] and the company relaunched as Amiga Corporation.^[12]

The Amiga hardware was designed by Miner, RJ Mical, and Dale Luck.^[13] A breadboard prototype for testing and development was largely completed by late 1983, and shown at the January 1984 Consumer Electronics Show (CES). At the time, the operating system was not ready, so the machine was demonstrated with the "Boing Ball" demo, a real-time animation showing a red-and-white spinning ball bouncing and casting a shadow; this bouncing ball later became the official logo of Escom subsidiary Amiga Technologies. CES attendees had trouble believing the computer being demonstrated had the power to display such a demo and searched in vain for the "real" computer behind it.^{[14][failed verification]}

A further developed version of the system was demonstrated at the June 1984 CES and shown to many companies in hopes of garnering further funding, but found little interest in a market that was in the final stages of the video game crash of 1983.^[11][15]

In March, Atari expressed a tepid interest in Lorraine for its potential use in a games console or home computer tentatively known as the 1850XLD. The talks were progressing slowly,^[16] and Amiga was running out of money. A temporary arrangement in June led to a $500,000 loan from Atari to Amiga to keep the company going. The terms required the loan to be repaid at the end of the month, otherwise Amiga would forfeit the Lorraine design to Atari.^[17]

Commodore[edit]

During 1983, Atari lost over $1 million a week, due to the combined effects of the crash and the ongoing price war in the home computer market. By the end of the year, Warner was desperate to sell the company. In January 1984, Jack Tramiel resigned from Commodore due to internal battles over the future direction of the company. A number of Commodore employees followed him to his new company, Tramel Technology. This included a number of the senior technical staff, where they began development of a 68000-based machine of their own. In June, Tramiel arranged a no-cash deal to take over Atari, reforming Tramel Technology as Atari Corporation.

As many Commodore technical staff had moved to Atari, Commodore was left with no workable path to design their own next-generation computer. The company approached Amiga offering to fund development as a home computer system. They quickly arranged to repay the Atari loan, ending that threat. The two companies were initially arranging a $4 million license agreement before Commodore offered $24 million to purchase Amiga outright.^[17]

By late 1984, the prototype breadboard chipset had successfully been turned into integrated circuits, and the system hardware was being readied for production. At this time the operating system (OS) was not as ready, and led to a deal to port an OS known as TRIPOS to the platform. TRIPOS was a multitasking system that had been written in BCPL during the 1970s for the PDP-11 minicomputer, but later experimentally ported to the 68000. This early version was known as AmigaDOS and the GUI as Workbench. The BCPL parts were later rewritten in the C language, and the entire system became AmigaOS.

The system was enclosed in a pizza box form factor case; a late change was the introduction of vertical supports on either side of the case to provide a "garage" under the main section of the system where the keyboard could be stored.^[18]

Launch[edit]

The first model was announced in 1985 as simply "The Amiga from Commodore", later to be retroactively dubbed the Amiga 1000.^[a] They were first offered for sale in August, but by October only 50 had been built, all of which were used by Commodore. Machines only began to arrive in quantity in mid-November, meaning they missed the Christmas buying rush.^[19] By the end of the year, they had sold 35,000 machines, and severe cashflow problems made the company pull out of the January 1986 CES.^[20] Bad or entirely missing marketing, forcing the development team to move to the east coast, notorious stability problems and other blunders limited sales in early 1986 to between 10,000 and 15,000 units a month.^[18] 120,000 units were reported as having been sold from the machine's launch up to the end of 1986.^[21]

Later models[edit]

In late 1985, Thomas Rattigan was promoted to COO of Commodore, and then to CEO in February 1986. He immediately implemented an ambitious plan that covered almost all of the company's operations. Among these was the long-overdue cancellation of the now outdated PET and VIC-20 lines, as well as a variety of poorly selling Commodore 64 offshoots and the Commodore 900 workstation effort.^[22]

Another one of the changes was to split the Amiga into two products, a new high-end version of the Amiga aimed at the creative market, and a cost-reduced version that would take over for the Commodore 64 in the low-end market.^[22] These new designs were released in 1987 as the Amiga 2000 and Amiga 500, the latter of which went on to widespread success and became their best selling model.

Similar high-end/low-end models would make up the Amiga line for the rest of its history; follow-on designs included the Amiga 3000/Amiga 500 Plus/Amiga 600, and the Amiga 4000/Amiga 1200. These models incorporated a series of technical upgrades known as the ECS and AGA, which added higher resolution displays among many other improvements and simplifications.^[23]

The Amiga line sold an estimated 4,850,000 machines over its lifetime.^[1] The machines were most popular in the UK and Germany, with about 1.5 million sold in each country, and sales in the high hundreds of thousands in other European nations. The machine was less popular in North America, where an estimated 700,000 were sold.^[1][24] In the United States, the Amiga found a niche with enthusiasts and in vertical markets for video processing and editing.^[25] In Europe, it was more broadly popular as a home computer and often used for video games.^[13] Beginning in 1988 it overlapped with the 16-bit Mega Drive, then the Super Nintendo Entertainment System in the early 1990s. Commodore UK's Kelly Sumner did not see Sega or Nintendo as competitors, but instead credited their marketing campaigns which spent over £40 million or $60,000,000 (equivalent to $130,000,000 in 2023) for promoting video games as a whole and thus helping to boost Amiga sales.^[24]

Bankruptcy[edit]

In spite of his successes in making the company profitable and bringing the Amiga line to market, Rattigan was soon forced out in a power struggle with majority shareholder, Irving Gould. This is widely regarded as the turning point, as further improvements to the Amiga were eroded by rapid improvements in other platforms.^[26]

Commodore shut down the Amiga division on April 26, 1994, and filed for bankruptcy three days later. Commodore's assets were purchased by Escom, a German PC manufacturer, who created the subsidiary company Amiga Technologies. They re-released the A1200 and A4000T, and introduced a new 68060 version of the A4000T. In 1996, it was reported that Escom had sold the Amiga intellectual property to VIScorp for $40m (equivalent to $71,750,000 in 2023).^[13] Amiga Technologies researched and developed the Amiga Walker prototype. They presented the machine publicly at CeBit,^[27][28] but this deal fell through, and Escom, in turn, went bankrupt in 1997.^[29][30]

A U.S. Wintel PC manufacturer, Gateway 2000, then purchased the Amiga branch and technology.^[13] In 2000, Gateway sold the Amiga brand to Amiga, Inc., without having released any products. Amiga, Inc. licensed the rights to sell hardware using the AmigaOne brand to Eyetech Group and Hyperion Entertainment. In 2019, Amiga, Inc. sold its intellectual property to Amiga Corporation.^[31][32]

Hardware[edit]

The Amiga has a custom chipset consisting of several coprocessors which handle audio, video, and direct memory access independently of the Central Processing Unit (CPU). This architecture gave the Amiga a performance edge over its competitors, particularly for graphics-intensive applications and games.^[33]

The architecture uses two distinct bus subsystems: the chipset bus and the CPU bus. The chipset bus allows the coprocessors and CPU to address "Chip RAM". The CPU bus provides addressing to conventional RAM, ROM and the Zorro II or Zorro III expansion subsystems. This enables independent operation of the subsystems. The CPU bus can be much faster than the chipset bus. CPU expansion boards may provide additional custom buses. Additionally, "busboards" or "bridgeboards" may provide ISA or PCI buses.^[33]

Central processing unit[edit]

The most popular models from Commodore, including the Amiga 1000, Amiga 500, and Amiga 2000, use the Motorola 68000 as the CPU. From a developer's point of view, the 68000 provides a full suite of 32-bit operations, but the chip can address only 16 MB of physical memory and is implemented using a 16-bit arithmetic logic unit and has a 16-bit external data bus, so 32-bit computations are transparently handled as multiple 16-bit values at a performance cost.^[34][35] The later Amiga 2500 and the Amiga 3000 models use fully 32-bit, 68000 compatible, processors from Motorola improved performance and larger addressing capability.

CPU upgrades were offered by both Commodore and third-party manufacturers. Most Amiga models can be upgraded either by direct CPU replacement or through expansion boards. Such boards often included faster and higher capacity memory interfaces and hard disk controllers.

Towards the end of Commodore's time in charge of Amiga development, there were suggestions that Commodore intended to move away from the 68000 series to higher performance RISC processors, such as the PA-RISC.^[36][37] Those ideas were never developed before Commodore filed for bankruptcy. Despite this, third-party manufacturers designed upgrades featuring a combination of 68000 series and PowerPC processors along with a PowerPC native microkernel and software.^[38][39] Later Amiga clones featured PowerPC processors only.

Custom chipset[edit]

The custom chipset at the core of the Amiga design appeared in three distinct generations, with a large degree of backward-compatibility. The Original Chip Set (OCS) appeared with the launch of the A1000 in 1985. OCS was eventually followed by the modestly improved Enhanced Chip Set (ECS) in 1990 and finally by the partly 32-bit Advanced Graphics Architecture (AGA) in 1992. Each chipset consists of several coprocessors that handle graphics acceleration, digital audio, direct memory access and communication between various peripherals (e.g., CPU, memory and floppy disks). In addition, some models featured auxiliary custom chips that performed tasks such as SCSI control and display de-interlacing.

Graphics[edit]

All Amiga systems can display full-screen animated planar graphics with 2, 4, 8, 16, 32, 64 (EHB Mode), or 4096 colors (HAM Mode). Models with the AGA chipset (A1200 and A4000) also have non-EHB 64, 128, 256, and 262144 (HAM8 Mode) color modes and a palette expanded from 4096 to 16.8 million colors.

The Amiga chipset can genlock, which is the ability to adjust its own screen refresh timing to match an incoming NTSC or PAL video signal. When combined with setting transparency, this allows an Amiga to overlay an external video source with graphics. This ability made the Amiga popular for many applications, and provides the ability to do character generation and CGI effects far more cheaply than earlier systems. This ability has been frequently utilized by wedding videographers, TV stations and their weather forecasting divisions (for weather graphics and radar), advertising channels, music video production, and desktop videographers. The NewTek Video Toaster was made possible by the genlock ability of the Amiga.

In 1988, the release of the Amiga A2024 fixed-frequency monochrome monitor with built-in framebuffer and flicker fixer hardware provided the Amiga with a choice of high-resolution graphic modes (1024×800 for NTSC and 1024×1024 for PAL).^[40]

ReTargetable Graphics[edit]

ReTargetable Graphics is an API for device drivers mainly used by 3rd party graphics hardware to interface with AmigaOS via a set of libraries. The software libraries may include software tools to adjust resolution, screen colors, pointers and screenmodes. The standard Intuition interface is limited to display depths of 8 bits, while RTG makes it possible to handle higher depths like 24-bits.

Sound[edit]

The sound chip, named Paula, supports four PCM sound channels (two for the left speaker and two for the right) with 8-bit resolution for each channel and a 6-bit volume control per channel. The analog output is connected to a low-pass filter, which filters out high-frequency aliasing when the Amiga is using a lower sampling rate (see Nyquist frequency). The brightness of the Amiga's power LED is used to indicate the status of the Amiga's low-pass filter. The filter is active when the LED is at normal brightness, and deactivated when dimmed (or off on older A500 Amigas). On Amiga 1000 (and first Amiga 500 and Amiga 2000 model), the power LED had no relation to the filter's status, and a wire needed to be manually soldered between pins on the sound chip to disable the filter. Paula can read arbitrary waveforms at arbitrary rates and amplitudes directly from the system's RAM, using direct memory access (DMA), making sound playback without CPU intervention possible.

Although the hardware is limited to four separate sound channels, software such as OctaMED uses software mixing to allow eight or more virtual channels, and it was possible for software to mix two hardware channels to achieve a single 14-bit resolution channel by playing with the volumes of the channels in such a way that one of the source channels contributes the most significant bits and the other the least.

The quality of the Amiga's sound output, and the fact that sound hardware is part of the standard chipset and easily addressed by software, were standout features of Amiga hardware unavailable on PC platforms for years^[b]. Third-party sound cards exist that provide DSP functions^{[citation needed]}, multi-track direct-to-disk recording^{[citation needed]}, multiple hardware sound channels and 16-bit and beyond resolutions. A retargetable sound API called AHI was developed allowing these cards to be used transparently by the OS and software.^[41]

Kickstart firmware[edit]

Kickstart is the firmware upon which AmigaOS is bootstrapped. Its purpose is to initialize the Amiga hardware and core components of AmigaOS and then attempt to boot from a bootable volume, such as a floppy disk or hard disk drive. Most models (excluding the Amiga 1000) come equipped with Kickstart on an embedded ROM-chip.

Keyboard and mouse[edit]

The keyboard on Amiga computers is similar to that found on a mid-80s IBM PC: Ten function keys, a numeric keypad, and four separate directional arrow keys. Caps Lock and Control share space to the left of A. Absent are Home, End, Page Up, and Page Down keys: These functions are accomplished on Amigas by pressing shift and the appropriate arrow key. The Amiga keyboard adds a Help key, which a function key usually acts as on PCs (usually F1). In addition to the Control and Alt modifier keys, the Amiga has 2 "Amiga" keys, rendered as "Open Amiga" and "Closed Amiga" similar to the Open/Closed Apple logo keys on Apple II keyboards. The left is used to manipulate the operating system (moving screens and the like) and the right delivers commands to the application. The absence of Num lock frees space for more mathematical symbols around the numeric pad.

Like IBM-compatible computers, the mouse has two buttons, but in AmigaOS, pressing and holding the right button replaces the system status line at the top of the screen with a Maclike menu bar. As with Apple's Mac OS prior to Mac OS 8, menu options are selected by releasing the button over that option, not by left clicking. Menu items that have a Boolean toggle state can be left clicked whilst the menu is kept open with the right button, which allows the user – for example – to set some selected text to bold, underline and italics in one visit to the menus.

The mouse plugs into one of two Atari joystick ports used for joysticks, game paddles, and graphics tablets. Although compatible with analog joysticks, Atari-style digital joysticks became standard.^[42] Unusually, two independent mice can be connected to the joystick ports; some games, such as Lemmings, were designed to take advantage of this.^[43]

Other peripherals and expansions[edit