Amiga 1000

The story begins in 1982, at a small Californian company called Hi-Toro, which soon afterwards became Amiga Corporation. In charge of the hardware was Jay Miner, who had already designed the graphics chips for Atari's 8-bit consoles and computers. The original plan was a games console codenamed Lorraine; to pay the bills, the company sold peripherals for the Atari 2600, such as the Joyboard, a platform you played by moving your body.

The video game crash of 1983 forced a change of course: the console became a computer. Amiga ran out of money, accepted a loan from Atari and, in August 1984, was bought by Commodore, which paid off that loan and took over the team and the chips.

The Amiga 1000 was unveiled on 23 July 1985 at the Lincoln Center in New York, on an evening when Andy Warhol painted a portrait of Debbie Harry live, on the computer itself. It cost US$1,295, without a monitor.

The processor is a Motorola 68000 at 7.16 MHz (7.09 MHz in the European PAL versions), but the heavy lifting is done by three custom chips, the so-called OCS (Original Chip Set). Agnus controls memory access and includes the Blitter, which copies and combines blocks of image data without tying up the processor, and the Copper, a coprocessor that changes video registers in sync with the screen's beam. Denise generates the image and the sprites. Paula handles sound, the floppy drive and the serial ports.

The memory shared by the chips is called Chip RAM: the A1000 came with 256 KB, expandable to 512 KB with a card that slotted in at the front. In HAM (Hold-And-Modify) mode, Denise shows all 4,096 colours of the palette at once, something far ahead of any home computer of the time. Paula has four 8-bit digital sound channels, two for each side of the stereo image.

There is one quirk only the A1000 has: it does not have the Kickstart (the core of the system) in ROM. When you switch it on, it asks for a Kickstart disk and loads it into 256 KB of write-protected memory, the WOM (Write Once Memory). Only then does it ask for the Workbench disk. The disks are 3.5-inch, holding 880 KB.

AmigaOS 1.0 had pre-emptive multitasking, something home PCs would only get many years later. The kernel, Exec, was written by Carl Sassenrath; the graphical interface is called Intuition and the desktop environment, Workbench. The part of AmigaDOS that manages files was adapted from TRIPOS, an academic system written in BCPL.

Commodore sold the A1000 as a machine for creative work: graphics, animation, music and video. It did not sell as well as it deserved, but it was the foundation for everything that came after.