A History of Atari’s 8-bit Personal Computers

The Atari 2600 was once the king of gaming consoles, but Atari was a late entrant to the personal computing field.

Atari Pong arcade consoleAtari got its start in 1972 with Pong, one of the earliest video consoles aimed at the arcade community. Pong was loosely based on ping-pong, and there were soon copycat games competing with it.

Pong home console

In 1975, you could play Pong on your TV.

In 1975, Atari sold a Home Pong game through Sears, which could be connected to a TV set and let people play Pong at home. Home Pong had the Sears Tele-Games brand; in 1976, Atari sold the same system under its own brand name.

Pong was too easy to copy, so Atari encouraged its team to develop more interesting games that would be harder to copy. Nolan Bushnell, one of Atari’s founders, started looking at how the company could create a video game console that would be able to play all of Atari’s games – four at that point in its history.

Atari Video Computer System

Atari VCS 2600The development team was stymied by the complexity of this project, and then in early 1976 MOS Technology introduced the 6502 CPU. This chip made it possible for Atari to develop its first gaming console, the Atari Video Computer System (VCS) – later to be known as the Atari 2600.

Atari Combat cartridgeThe VCS debuted on September 11, 1977 at US$199 with two joysticks, two paddles, and the Combat game cartridge. It was also sold as the Sears Video Arcade. The genius of the system was its use of game cartridges, which made it easy to switch games but initially difficult for other companies to produce.

Atari had 8 other titles when the VCS launched and sold 250,000 units in 1977. In 1978, an additional 800,000 were manufactured but only 550,000 sold. In 1979, Atari sold 1 million units.

In January 1980, Atari released Space Invaders, which it had licensed from Taito. Sales surpassed 2 million systems in 1980 and doubled that in 1981. By 1982, Atari had sold 10 million consoles, and it had also sold 7 million Pac Man cartridges for the VCS.

Problem was, Atari’s Pac Man wasn’t nearly as good as the arcade game, and then Atari’s E.T. the Extra-Terrestrial, rushed to market for the 1982 holiday season, became the biggest commercial failure in video game history.

The video game crash of 1983-85 is in part attributed to this disaster. The industry peaked with revenues of $3.2 billion in 1983 and then went into freefall, dropping to roughly $100 million in 1985. This pretty much marked the end of the line for second generation consoles such as the Atari 2600, Magnavox Oddyssey2, ColecoVision, and Mattel Intellivision.

Atari’s First Computers

Video game consoles were also seeing competition from personal computers, such as the Commodore VIC-20 and 64, Radio Shack TRS-80 Color Computer, TI 99/4A, and Atari 400.

Atari’s 8-bit computers grew out of a project to build a next generation successor to the Atari 2600. With home computers taking off, Atari decided to add a keyboard to the new device, resulting in the Atari 400 and 800 home computers – complete with game cartridge slots. These were released in November 1979 and built around the same 6502 processor used in the Atari VCS, the Apple II, and Commodore’s early personal computers.

Atari 800

Atari 800

The Atari 800 was the US$999 flagship model with a full keyboard, a 1.79 MHz CPU (competitors ran at 1 MHz), 16-color graphics with a resolution of 320 x 192 pixels, four game controller ports, two cartridge slots, and 8 KB of memory (with a 48 KB maximum). By changing the color palette on each scan line, the Atari computer could display 128 colors with the original CTIA graphics chip and 256 colors with the later GTIA graphics chip.

Atari BASIC came on a separate cartridge. Unlike competitive computers, BASIC was not built into the Atari 800 or 400.

Atari 400

Atari 400Introduced at the same time as the Atari 800, the 400 was its cheaper (US$495), compromised sibling. Instead of a keyboard with real keys, the 400 had a membrane keyboard – okay for games, but not for coding or word processing. Once cartridge slot instead of two – although the second slot was rarely used. No composite video port, just an RF modulator so it could be hooked up to a TV.

The 400 originally shipped with 4 KB of memory, then with 8 KB, later with 16 KB, and Atari later released an upgrade to 48 KB of memory. The 4 KB version didn’t have enough RAM to support a floppy drive.

Third-party manufacturers offered real keyboards and memory expansion modules, and it was fairly easy to hack the Atari 400 and give it composite video output.

Despite its limitations and because of its much lower cost, the Atari 400 outsold the 800 by a 2-to-1 ratio.


Peripherals were connected to the Ataris using its Serial Input/Output (SIO) bus, which allowed devices to be daisy-chained – similar to the far later USB. The drawback was that devices needed to be intelligent to communicate with the computer, which drove up prices. When the system booted up, it would download drivers from devices on the SIO bus.

SIO devices included floppy drives, tape decks, printers, modems, and expansion boxes.

Sweet 16 and the Atari 1000

In April 1982, the first draft for Atari’s next generation of home computers was written that would replace the expensive Atari 400 and 800. Known as the Sweet 16 Project, these documents were updated until June 11, 1982 and proposed a new model to be known as the Atari 1000.

The new model would come in 16 KB and 64 KB versions but otherwise be identical. They would come in a slimmer case with enhanced SIO connectors and a new PBI (Parallel Bus Interface) that would provide 8-bit access to every chip in the system. Atari also planned a 5-slot Atari 1090 XL Expansion System, which would let it compete with the Apple IIe.

However, the Atari 1000 never saw the light of day, and the computer Atari did release, the 1200XL, lacked most of the high-end features planned for the 1000.

Atari 1200XL

Atari 1200XLThe US$899 Atari 1200XL (the XL stood for Extended Line), shipped in March 1983 with 64 KB of memory standard, an improved keyboard over the Atari 800, and the slimmer case design proposed for the Atari 1000 – Atari moved the cartridge slot from the top to the left side. It was the first computer to use the 6502C CPU, a modified version of the 6502 with a HALT signal on pin 35 and a second R/W on pin 36.

One of the big improvements is that sounds formerly heard from the Atari’s built-in speaker were now routed to a connected TV, monitor, or set of external speakers.

One of the big problems is that because of all the changes, many third-party and even some Atari programs were not compatible with the 1200 XL, and losing two of the four game ports on earlier models was seen as a step backward by many gamers on the Atari platform.

Except for the SIO ports, the 1200XL was a closed system – fine for consumers but not what hobbyists wanted. Some consider this the Edsel of the Atari 8-bit line because of this. Sales of the Atari 800 actually increased after the introduction of the 1200XL. (By July 2983, the Atari 800 was selling for US$165!)

Some consider the keyboard on the 1200XL to be the best on any 8-bit Atari. The 1200XL was only produced for the NTSC market; there was no PAL version for the European market. It was discontinued in June 1983, just three months after its release.

Commodore Kills Off Texas Instruments’ Home Computer

The most important development in 1983 was the home computing price war. Texas Instruments had nearly destroyed Commodore International when it began selling fully assembled calculators for less than Commodore and other calculator manufacturers paid for components.

Texas Instruments TI-99/4A computer system

Commodore had purchased MOS Technology, which produced the popular 6502 CPU used in Apple, Atari, and Commodore computers, along with other chips. This gave Commodore the edge it needed to do to Texas Instruments in the personal computer world what TI had done to Commodore in calculators.

In June 1983, Commodore slashed the Commodore 64 to $299, and some retailers sold it for as little as $199. At the time, Commodore was selling as many home computers as the rest of the industry. Texas Instruments was ready to launch its budget 99/2 for $99, but the 99/4A had already been slashed to that price.

Texas Instruments was losing money on every computer sold, losing hundreds of millions of dollars in the 1983 PC price war. TI threw in the towel in October 1983. At one point it had accounted for one-third of the home computer market, but even the mighty TI could not compete with Commodore – which hurt itself financially in order to get back at it former supplier.

And, of course, Atari had to slash prices in this environment.

Atari 600XL and 800 XL

Atari 600XLThe Atari 1200XL had bombed, and the Atari 800 had been unloaded for as little as $165 in the PC price war. Atari needed to move forward, and at the Summer 1983 Consumer Electronics Show (CES), it announced the Atari 600XL and 800 XL. The new models had similar styling to the 1200XL but were less deep front-t0-back, and they had built-in Atari BASIC. They also included the Parallel Bus Interface (PBI) that Atari had developed as part of its Sweet 16/Atari 1000 project.

Two other models, the 1400XL and 1450XL, were announced at the same time but never made it to market.

Atari 800XLTo compete in the ongoing price war, Atari moved production to the Far East, which created some delays. The new models, planned for mid-1983, didn’t arrive until late 1983. Even then, they were in limited supply, while the Commodore 64 was available everywhere.

Between the video game crash and the PC price war, Atari was hurting, losing millions of dollars every day.

Atari 65XE and 130XE

In January 1984, Commodore got rid of Jack Tramiel, who went on to purchase the Atari home computer and video game division from Warner Communications in July 1984 for a song. In 1985, the 600XL and 800XL were replaced by more economical versions while Tramiel put the focus on the next generation Atari ST, which would compete with Macintosh and Amiga computers starting in 1985.

Atari 130XEThe Atari 65XE was essentially an 800XL without its parallel bus (PBI), while the 130XE was a 128 KB version of the 800XL and had a parallel interface – ECI for Enhanced Cartridge Interface – that wasn’t compatible with PBI. Later revisions of the 65XE included ECI. The 65XE was sold as the 800XE in some European markets to benefit from the success of the Atari 800XL there.

The end came for Atari’s 8-bit line on January 1, 1992 – 20 years after Pong, 15 years after the Atari VCS, and 12 years after it entered the home computer market. The Atari ST line would only go on for another year as Atari chose to put its focus back on gaming consoles.

Further Reading

Keywords: #atari #atarivcs #atari2600 #atari400 #atari800 #atari1200xl #atari65xe #atari130xe #atarihistory #6502 #6502cpu #mostech6502

Short link: http://goo.gl/HcCPAZ

searchword: 8bitatari