Amiga 500

Amiga 500
Type	Home computer
Key terms	custom graphics/audio chips; preemptive multitasking; demo scene
Related	AmigaOS; Motorola 68000; Amiga 1200
Domain	Computers
Introduced	1987
Manufacturer	Commodore
Examples	Deluxe Paint; Shadow of the Beast; Workbench 1.3
Wikidata	Q384656

Definition and Scope

The Amiga 500 (A500) is a home computer introduced by Commodore in 1987. It combined a Motorola 68000 CPU with custom chips for advanced graphics and sound. Its operating system (AmigaOS) offered true preemptive multitasking and a graphical desktop environment – features rare in consumer machines at the time. This made the A500 exceptionally capable for multimedia tasks. Indeed, it gave consumers audio-visual “multimedia” power years before that term was common in PCs.

The Amiga 500 went on to become Commodore’s best-selling Amiga model and a popular platform for gaming, animation, and the demo scene. It was followed by minor revisions (the Amiga 500 Plus in 1991 and the Amiga 600 in 1992), but the original 1987 A500 remains the classic model. In total, the Amiga line sold around 5 million units, with the A500 as the most numerous model.

Historical Context and Evolution

Commodore acquired Amiga Corporation in 1984 (around the time founder Jack Tramiel left the company) and completed development of its 16-bit chipset. The Amiga 1000 debuted in 1985, and the Amiga 500 was introduced in April 1987 as a lower-cost successor. By packaging the CPU, custom graphics/audio chips, and keyboard in a single “pizza-box” case, Commodore aimed the A500 squarely at home users and gamers. It quickly became very popular in Europe (selling millions of units) and was often promoted as a “computer of the future,” with live demonstrations of video editing, animation, and music production. For example, Commodore’s 1987 ads boasted video creation and sound synthesis running simultaneously – feats beyond any rival PC of the era. Key competitors were the Atari 520ST and early IBM PC compatibles.

Later Amiga models (such as the 500 Plus, 600, and 1200) added more memory and improved graphics chips, but Commodore’s financial troubles meant the Amiga line faltered by the mid-1990s. Still, during its heyday the Amiga 500 stood out for its capabilities and remained popular well into the early 1990s.

Architecture and Core Features

The Amiga 500’s hardware was unusual: it combined a 68000 CPU with specialized coprocessors for graphics and sound. Denise, the video display chip, managed the screen output. It processed multiple bitplane (pixel) layers and up to eight hardware sprites in real time. In normal mode the A500 could show 32 colors at once (from a 4,096-color palette) on two independently scrolling backgrounds, all handled by Denise’s hardware. A special “Hold-and-Modify” mode even allowed all 4,096 palette colors to be used in one image. In practice, this meant the CPU was largely free from drawing tasks, since Denise did the rendering internally.

Agnus contained two coprocessors: the blitter and the copper. The blitter was a hardware engine that could very quickly copy or fill blocks of video memory – useful for moving images (sprites) and filling shapes – without CPU intervention. The copper was a tiny self-running program synchronized with the video beam. Programmers wrote “copper lists” that told it to change graphics registers at specific times during the screen refresh. For example, the copper could automatically adjust colors or scrolling partway down the display, creating special effects (color gradients, split-screen modes, etc.) without extra CPU overhead.

Paula was the audio-and-I/O chip. It offered four independent 8-bit PCM sound channels (effectively two stereo pairs), allowing the A500 to play four digital audio samples or music tracks simultaneously – unheard of on most PCs then. Paula also managed the floppy drive and serial/parallel ports. Because Paula used DMA (Direct Memory Access), sound playback and disk I/O happened in parallel while the CPU continued running programs.

In a stock Amiga 500, the CPU and these chips shared 512 KB of “chip RAM” on the motherboard (expandable to 1 MB via a memory upgrade), and the system used a 256 KB ROM (the Kickstart) for the core OS. A wide range of expansions (hard-drive controllers, modems, CPU-accelerator cards, etc.) were available on the market. By offloading video and audio work to its dedicated hardware, the Amiga 500 achieved smooth animation and rich stereo music that few other home computers of the late 1980s could match.

Operating System and Software

On startup, the Amiga 500 loaded Workbench, its graphical desktop environment with icons and windows controlled by a mouse. AmigaOS supported true preemptive multitasking: users could run multiple applications at once (for example, editing text in one window while a music player ran in the background). Part of the OS lived in ROM (Kickstart), and additional software modules loaded from floppy disk as needed.

The A500’s software library was broad. Many games took advantage of its hardware: for example, the puzzle game Lemmings and the platformer Shadow of the Beast featured detailed graphics and multi-channel sound unique to the Amiga. Artists commonly used Deluxe Paint for graphics and frame-by-frame animation. Musicians used tracker programs (like ProTracker) to compose music that fully exploited the Amiga’s four audio channels. Productivity titles – word processors, spreadsheets, and early desktop-publishing tools – were also available, though the machine’s niche remained creative and entertainment software. (Later Amiga models – especially when fitted with add-ons like the Video Toaster – were used for video editing and broadcast graphics, blurring the line between home and studio computers.)

Gaming and the Demo Scene

The Amiga 500 found a passionate audience in gaming and in the demoscene. In the demoscene, hobbyist programmers created non-interactive demo programs to showcase impressive graphics and music. These demos often included dazzling effects – color bars, copper-driven visual tricks, and 3D wireframe animations – all set to multi-channel soundtrack. The A500’s advanced audio/video hardware made it one of the premier demo platforms of the time, inspiring techniques that later spread to other platforms.

Commercial games also leveraged the A500’s strengths. Beyond Lemmings and Shadow of the Beast, titles like Another World (1991) and Wings (1990) used smooth animations and rich sound to great effect. Interestingly, many demo coders became game developers, so innovations in demos (fast blitter-graphics routines, tracker music) often appeared in Amiga games. The synergy between the demo and gaming communities highlighted the A500’s multimedia prowess and helped build its legendary reputation.

Legacy and Impact

The Amiga 500’s influence on technology and culture is still evident. It was one of the first home computers built expressly for multimedia: having dedicated audio channels and graphics hardware in one box was revolutionary. (By comparison, mainstream PCs did not gain true preemptive multitasking until the mid-1990s.) Many concepts from the Amiga – hardware sprites, blitters, coprocessors – anticipated ideas in later graphics and sound systems. Its affordability and power helped train a generation of game developers, musicians and digital artists.

After Commodore went bankrupt in 1994, a loyal community kept the Amiga spirit alive. Software emulators (such as WinUAE) allow Amiga 500 programs to run on modern PCs. New hardware projects and OS ports (like AmigaOS 4 and the open-source AROS) continue the platform’s vision. Even decades later, the A500’s graphics-and-sound combination still impresses retrocomputing fans. For example, early CGI space scenes in the TV series Babylon 5 were rendered on Amiga workstations. The creativity the Amiga 500 enabled – in games, demos, and animation – maintains a devoted following, and its legacy as a pioneering multimedia home computer is firmly cemented in computing history. It even allowed small studios and hobbyists to attempt video and graphics effects previously limited to expensive workstations.