Inside the Atari 800

This is the computer that started it all. The original, the OG, the Atari 800. First released in 1979 (along with the Atari 400), the Atari 800 was a powerful personal computer with ground-breaking graphics capabilities. I recently picked up an Atari 800 on Facebook Marketplace, so let’s take a closer look at it.

The first thing to notice if you’ve never seen one in person is that the Atari 800 is a big boy. Here you can see it on my desk next to my 130XE. It absolutely towers over it. It could swallow up the 130XE inside its rusty innards with room to spare.

The next immediate observation is that the keyboard is amazing to type on. The keys are tall, sculpted and have great feedback. That poor 130XE keyboard is no match for it.

This Atari 800 works very well, with only a couple issues I noted, both having to do with the keyboard. First is that the return key requires a firm press for it to register. And the break key, just above it, does not seem to work at all.

I was finally able to test my Gorf cartridge, which is not compatible with XL/XE machines, and it worked great on the 800.

If you need some cartridges for you Atari 8-bit, there are still several available in the Goto 10 Store, including Star Raiders, Pac-Man, Donkey Kong and more.

Looking at the outside of the Atari 800, its ports are on the front and the right side. The front contains the four joystick ports. Subsequent Atari 8-bits had just two joysticks ports.

The right side contains everything else. From left to right, there is the monitor port, Serial I/O port, TV channel selector, power switch and power port.

I guess you could say the cartridge slots are also ports and they are on the top, under a trap door. Yes, the 800 is the only Atari with two cartridge slots.

Also on the back is a fixed RF wire for connecting to a TV. It’s annoying that this cannot be unplugged from the outside, but it can be unplugged from the inside and once I got everything open, I disconnected and removed it since I’ll only be using the monitor port.

At the bottom of the unit you can see the original sticker. This Atari 800 was made in the US.

With it upside down, there are four screws that can be removed to take off the bottom cover.

The motherboard is actually attached the top of the computer, unlike the other Atari computer designs. Another thing to note is the built-in speaker, which makes a chirping noise as you type. Later Ataris did not have a built-in speaker as all sound was sent to the TV or monitor.

To detach the top case, you first have to remove the secret cover that is over the expansion cards. Yes, the 800 was the only Atari 8-bit computer with internal expansion capabilities.

It is really cool that the OS was on its own expansion card. And the RAM cards were also neat and incredibly well designed. The three 16K cards gave this Atari 800 its maximum of 48K RAM. I especially like the little diagrams printed on them to show you how they can be installed.

This the “trap door” part of the top case after it has been removed.

And here is a view with the expansion cards all removed.

With all these cards removed, there are more screws on the back to take out so that the top cover completely comes off. This reveals the main core of the computer.

Here’s a close-up of the circuit board on the right side.

The main motherboard is actually underneath that giant aluminum shielding. I decided I didn’t want to take it apart further at this point. This is an old computer and although it doesn’t seem particularly fragile, I didn’t want to risk damaging anything. Here is a picture from Wikicommons that shows what is under there, though:

And now, here are all the parts that I disassembled.

I then buttoned it all back up and tested it to make sure it all still worked. Fortunately, that was successful!

I look forward to playing with this 800 more and testing it out with the various software, games and programs I have.