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Atari 400 vs Commodore VIC-20

When we think of Atari versus Commodore, the Commodore 64 generally comes to mind. But there is an argument that the Commodore VIC-20 did as much damage to Atari as the Commodore 64 did, and possibly more. Let’s compare and contrast the Atari 400 vs Commodore VIC-20, which is a classic case of winning the battle but losing the war.

Entry level computers

Atari 400 vs Commodore VIC-20

In 1982, the Commodore VIC-20 had a price advantage over the Atari 400. In 1984 when that reversed, VIC-20 sales nosedived.

Both the Commodore VIC-20 and Atari 400 were designed to be entry level computers. But the two companies came at them from a very different angle.

In 1979, Atari set out to design the best computer they could at a price point of about $1,000. That computer was the Atari 800.

They planned a video game console based on the same architecture that would be compatible. Then they changed plans and added a membrane keyboard to it to turn it into a low end computer. The result was a lot like the 800 with a cheaper keyboard. It lacked the monitor port, the second cartridge slot and had less memory. The result was a cut down version, the Atari 400, for several hundred dollars less.

Commodore took a different approach. They wanted to build a computer with color that cost $299. It wasn’t an entirely new design. They were certainly able to borrow heavily from the existing pet computer line, but the VIC-20 wasn’t fully compatible with anything else Commodore made before or after. It was similar enough that porting software between the machines was straightforward. But the VIC-20 was built with the minimum viable product mindset.

Market positioning

The VIC-20 undercut the Atari 400 in price, but Commodore didn’t go after the 400. They went after the Atari 2600 game console. The pitch was that you could buy a video game console, or you can pay a little bit more and get an actual computer, and then you could play video games and you could use it for more serious things too, like writing letters, doing homework, and even entering the world of telecommunications.

Commodore sold about 3 million units, most of them between 1981 and 1983. That’s just a dent in Atari 2600 sales. That console sold 20 million units. But it represented a lost opportunity for Atari.

The reason I say that is because when the US video game crash happened in 1983, Atari was not positioned to capitalize much on it. Commodore won with an inferior machine because Commodore was able to define the terms, and characterize Atari as a maker of game consoles. And I will argue that Atari did not do a good enough job telling consumers that they also make great computers, not just video game consoles.

And yes, I said it. In every regard except for the keyboard and the price, the Atari 400 was a much better computer.

Atari 400 vs Commodore VIC-20: Graphics

The VIC-20 didn’t have the worst graphics capability of its generation, but the Atari 400 had the best. The Atari 400 could display up to 128 colors and had the ability to display sprites. It lended itself exceptionally well to the types of games that were common in the early 1980s, and Atari ported very good versions of its arcade hits, along with other hit titles that it licensed. The Atari 400 was the first system that could claim to be able to play arcade quality games at home, because it was doing it in 1979 and 1980.

The VIC-20 had rudimentary graphics capabilities. It could display 16 colors, but there were limitations on how you could use 8 of them. But it didn’t have hardware sprites. And it lacked a true bitmapped graphics mode. Instead, it had a redefineable character set. You could fake bitmapped graphics by filling the screen with characters and then redefining the characters, or you could use the characters as tiles, program them to look how you want, and then build the screen with those. And since the display was only 22×23, a single character was nearly the size of a sprite on other systems.

It was possible to make good games on the VIC-20 in spite of its limitations, but the 400 gave developers a lot more to work with.

Atari 400 vs Commodore VIC-20: Sound

The VIC-20 could only do square waves on three of its voices and noise on its fourth voice. Atari had 4 voices, and you could play square waves on any of them. Getting more complex waveforms was doable by pairing voices. Both sound chips had limitations but the Atari was more versatile.

The sound on the VIC-20 was competitive with the TI and AY sound chips used in so many of the game consoles and other home computers of this generation, but Atari outclassed it.

There was a good reason for this. Atari had a single chip dedicated just to producing sound. The graphics functions were split between two chips. Commodore crammed the sound and graphics onto a single chip. With 1/3 as much silicon to work with, they weren’t going to go head to head with Atari on capability.

Atari 400 vs Commodore VIC-20: Memory

The Atari came with 8K or 16K of RAM, depending on when you bought it. It was officially possible to upgrade to 32K, and unofficially to 48k.

The VIC-20 came with an oddball 5K of memory, and that decision was based on the surplus parts Commodore head in its warehouse at the time. When Commodore didn’t expect a machine to last long in the marketplace, it would make design decisions like that.

Commodore provided memory upgrades in 8K increments. The maximum amount of memory you can put on a VIC-20 varies, but modern memory expansions can expand a VIC-20 to 35K of usable memory.

The CPU in both machines could address up to 64K of RAM, but both of them had to allocate some of that address space to ROM and I/O. The VIC-20 had the Basic programming language in ROM, so that was part of the reason you couldn’t expand a VIC-20 to 48k like the 400.


When you powered on the VIC-20, it booted into a programming language called Basic. The Atari 400 didn’t include Basic, you had to buy a separate cartridge. It also made it difficult to sell commercial programs written in Atari Basic, because you couldn’t necessarily assume everyone had the Basic cartridge.

Commodore also included a manual that taught you how to program it.

It seems that Atari wasn’t sure if consumers would want to program their computers themselves, while Commodore actively encouraged it. Not all of the software people created themselves for their VIC-20 was a masterpiece, of course, but it did help create a large ecosystem around the machine.

We didn’t call it open source at the time, but there was a thriving seen around home computers that resembled the modern open source movement. A large number of monthly magazines published computer programs that you could type in yourself, save to tape or disk, modify for your own purposes, or just use.
Many of the magazines employed staff programmers, but as time moved on, and increasing amount of the software they published was contributed by readers.

For a computer that had maybe two and a half Good years on the market, the VIC-20 built up a very impressive software library in a very short time frame.

Sales figures

We don’t have exact sales figures for either machine. Based on what Commodore did say, we can estimate about 3 million VIC-20 computers sold between 1981 and 1985, with the majority of those sales occurring in 1983 and earlier. Estimates on Atari 400 sales are really hard to find, but I found an estimate of 1.3 million units.

Naturally, the Atari 400 was one of the machines Commodore expected to compete with, but the VIC-20 was really aimed more directly at Texas Instruments. Commodore’s strategy for competing with the 400 was to pretend it didn’t exist, and instead aim at the Atari game consoles in its advertising.

Atari sold around 4-5 million across its 8-bit line. The Atari 400 machines were a pretty hefty chunk of that. The 800XL, at 2 million units, was the only model in the line that outsold the 400.

The end of the VIC-20

VIC-20 sales nosedived in 1984. The conventional wisdom is that the Commodore 64 was cheap enough by 1984 that the VIC-20 no longer made sense. But I think Atari had something to do with it.

Over the course of 1984, Atari, under the new ownership of Jack Tramiel, flooded the market with 400, 800, 600XL, and 800XL computers at blowout prices. At $70, the 400 cost less than a VIC-20 in spite of being a better computer in every way other than the keyboard. At $100, the 600XL cost about the same as a VIC-20 and addressed the keyboard problem.

Atari was trying to compete with the Commodore 64, but they really ended up competing with the VIC-20. They gave off a vibe of giving up, because they didn’t advertise the computers at all, they just slashed the prices and the retailers bragged about buying truckloads of machines and blowing them out.

What about today?

Both computers have a compelling homebrew scene today, although for slightly different reasons. Both of them are challenging to program, and that’s part of the reason modern programmers are drawn to both machines.
The difference is the 400 isn’t the optimal Atari 8-bit for running modern homebrew software. It looks neat as a display piece, and it can run the older software But the other machines and the product line are nicer to use. They have more memory, take more memory, and have nicer keyboards.

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