Retro Home Computers – Commodore Amiga 1000



Commodore Amiga 1000,
1985 – 1987

Generations Ahead of the Competition

At the time of its introduction in 1985, the Amiga had what was a complex overall architecture, featuring coprocessors designed for audio, video, ports, and DMA tasks (25 channels). The custom chipsets’ two primary functions were to reduce CPU overhead, and to perform specialized tasks for which they were highly optimized. This accounted for much of the speed and throughput improvement of this open architecture design.

Commodore Amiga 1000

Above: The first Amiga – the Commodore Amiga 1000

It is interesting to note that while the CPU was triggered on the rising edge of the clock, the custom chips were triggered on the falling edge, architecture similar to the DDR memory scheme. With its stereo sound, comparatively large colour palette and brisk performance, and its multitasking abilities, the Amiga was arguably 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: 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 colours 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, 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.

Lincoln Center

Commodore introduced the Amiga 1000 with much fanfare at the Lincoln Center in New York on July 23, 1985. It was the most advanced computer of its day. The Amiga 1000 was originally conceived a few years earlier by a small California company called Amiga Inc. and was financed by a group of Florida doctors looking to invest in a killer game machine. The prototype machine was codenamed ‘Lorraine’.

Commodore 128D

Above: Andy Warhol and Debra Harry at the launch of the Amiga 1000

During the design phase the company ran into financial difficulties and ran out of money. They soon were looking for a buyer to bail them out. Two interested buyers came to the forefront. In early 1984 Jack Tramiel, the founder of Commodore Business Machines, left the company and sold all his stock over a power struggle with Irving Gould, the CEO of Commodore.

Jack Tramiel

Tramiel purchased the Atari Consumer Division subsidiary from Time-Warner, he folded into Tramiel Technology Ltd (TTL), which was then renamed in to Atari Inc. Time-Warner was happy to be rid of it as it was losing lots of money. Seeing that the 8-bit computer market was beginning to collapse, Tramiel saw Lorraine as a golden opportunity to get a new advanced technology without spending any money or time on research and design. He made an extremely low offer to buy the outstanding stock of Amiga Inc. and gain access to the Lorraine technology behind the computer. Being desperate this offer was tentatively accepted by the Amiga Company.

Commodore, also realizing that it’s position in the home computer market was in jeopardy unless they came up with the new technology to replace the aging but still popular C-64, saw the golden opportunity.

Atari, was not interested in a purchase of the company Amiga. Atari was more interested in the technology behind the Amiga prototype. Negotiations between Atari (Time Warner) and Amiga Inc started in the Fall of 1983. Negotiations continued with Amiga during the January 1984 CES and signed in early March of 1984. The deal was for Warner and Atari to join the already several investors Amiga had, by providing a $500,000 payment. The payment and contract were for several things:

1) a guarantee that in return they’d do a full licensing contract together in late June when the chipset was to be delivered. As part of the guarantee, all technical documents were kept in escrow until the signing of the contract. If Amiga were to fold, as Atari believe was a high probability, Atari Inc. would gain access to the documents in escrow and no longer need to negotiate a license as a recoup of it’s investment;

2) To gain access to Amiga’s engineers and the still in development chipset. The initial contract was for Atari to develop a game console based on the Amiga chipset, to be released that Fall that was codenamed Mickey. Mickey would then be expandable in to a full computer, which would be due out sometime in 1986. Atari also intended to use the chipset in coin-op boards as well; and

3) Upon delivery of the three chips in late June and signing of the licensing agreement, Atari would pay $500,000 per chip. They also agreed to buy 1,000,000 preferred shares at $3 a share, and pay a license fee of $2 per unit royalties on consumer and computer products, plus a guaranteed minimum of $100,000 per year from coin-op sales at $15 per unit sold.

The Amiga was an amazing computer in its time and for several years thereafter. It was based on the Motorola 68000, a 32-bit processor with 16-bit pathways. The Apple Macintosh used the same processor in its 1984 Macintosh computer. The Amiga was half the price of the Mac, but offered several technology improvements.

GUI Operating System

Like the Macintosh, the Amiga came with a graphical operating system, however, the Amiga’s operating system went one step further, it offered pre-emptive multitasking <96> a first for the home computer market, which was years ahead of other major platforms by as much as 10 years.

Although the Amiga used the same processor at about the same clock speed of the Mac, it was considerably faster due mostly to the several custom chips inside acting as coprocessors to handle such things as video, graphics, IO and sound processing, relieving the burden on the CPU.

Commodore 128D

Above: Amiga 1000 operating system called Workbench

It had a 4096 colour pallet 4096 with a resolution of 640 x 400 bits, while the PC and its compatibles were still wallowing in CGA with 16 colours at 3 times the cost. The Amiga came with a four-channel 8-bit stereo sound capable of sampling rates of 44,000KHz.

The Amiga came standard with 256KB RAM with room for a 256KB plug in RAM cartridge to bring the total to 512k, though the total RAM accessible by the processor was 9 MB. The 96 key keyboard of the Amiga 1000 is connected through a port on the back of the computer and the keyboard slides into a unique ‘garage’ built for it under the front of the computer.

The rear of the computer has a row of D-type plugs for hooking up the peripherals of the computer. Starting from the left side is the modular telephone style keyboard plug, next is the industry standard Centronics parallel port for a standard PC printer, then the disk drive port for connecting an external floppy drive, a standard RS-232 port for connecting a modem, right and left RCA type plugs for stereo audio outputs, and three video ports.

The Amiga’s video output ports made the Amiga very versatile. The first is a 23 pin D-plug for hooking to an analogue RGB monitor such as the Amiga 1080 monitor, the second is a 9 pin round DIN plug for hooking to a composite colour monitor , and an RCA type plug outputting an RF composite video signal.

Built into the Amiga is an 880-kilobyte double-sided double-density floppy drive. The start up files for the computer curiously was not included in ROM but on a disk called Kickstart. This was probably because at the time of its release the OS and startup program were not completely ready and had a few bugs.

Atari 520ST

Atari 520ST

Above: Atari 520ST

Commodore rushed the Amiga out to market early due to pressure from the Atari 520ST, which was released several months earlier by Jack Tramiel, who felt that Commodore stole the Lorraine from him with a last minute bid. Commodore was afraid that they would lose valuable market share and be unable to regain it.

Amiga Lorraine Breadboard Prototype

Above: Amiga prototype codenamed Lorraine. This prototype was presented at the CES show in 1984.

The Amiga prototype was rushed into production and the buggy Kickstart 1.0 was sent with it. Commodore figured if they didn’t burn it into RAM it would be easier to fix it later with an upgrade disk (where have we heard that before!).