Housing a Linux computer inside a broken Atari 2600 cartridge

 I started thinking pretty soon after completing the custom cable channel project of housing a Raspberry Pi UNO into a repurposed cable box from the 1980s about other novel and interesting ideas to house single board computers. I recently was tidying up my work space and my eyes fell on a stack of Atari 2600 cartridges that failed to boot when testing them. It was during the process of taking the casing for a fairly grimy copy of Surround apart it dawned on me that these cases are the perfect size to house a Raspberry Pi Zero W, which I happened to have a couple just sitting on the desk mocking me for not using them.

The first stage was to completely disassemble the old cartridge, which honestly is a bit more challenging than it probably should be. I got pretty lucky removing the original labels, so I was able to reuse them after everything is assemble. There is only 1 phillips head screw to remove, but there are 6 plastic clips which require you to deal with before the casing will come apart. I used a small sized slotted screwdriver to carefully push the clips in and manage to get the thing apart, but I could definitely see people breaking the tabs and/or scarring up the plastic of the cartridge while trying to get these things disengaged. After that it's pretty straightforward. The dust cover assembly slides out, and nothing is holding the game ROM in place. I opted to save my ROM, since I'm still going to see if I can rehab the pins to check if it might actually boot after a good scrubbing.

The next step was to hot glue the offsets in place inside the cartridge to mount the Raspberry Pi. I decided to run a very bare bones distro of the Raspberry Pi OS Lite (32-bit) which comes with no desktop. My goal here is a totally basic Linux system hidden inside an old Atari cartridge. Maybe I'll install Stella or some other 2600 emulator on it at some point - I imagine it would be pretty cool to play 2600 games on a computer housed inside an actually 2600 game.

After testing to make sure everything worked, I reassemble the case and glued the orginal labels back into place. Since the Pi Zero W uses 2 micro USB connections (one for USB stuff and one to power the board) I decided to put a red dot of paint underneath the power connection, since you can't easily read the board to prevent me from inadvertently mixing up the connections.

 Fun project that was totally a spontaneous use of time that I should have allocated to doing something else. 

Are You Keeping Up With the Commodore?

The Commodore 64 was an amazing computer, for a number of reasons. It's arguably not only the best-selling home computer of all time, but the one machine that really was able to change the opinion of the masses in terms of how computers could be used. It was the perfect fusion of game machine and home computer, something that other companies during the 1980s had a hard time keeping up with.

 

The downside of all old technology is that things break. I had noticed that the sound quality produced by my Commodore 64 was distorted during some programs. A good example would be the introduction to Activision's "Ghostbusters", when it plays the theme song. Some parts were fine, but others were either extremely distorted or in extreme cases not even present. This is a classic symptom of a failing SID chip in the old Commodores. The SID chip, otherwise known as the "Sound Interface Device", is the IC responsible for producing the lush, 80's sound that the C64's were renown for. The SID was extremely advanced in terms of its ability to produce a wide range of sounds, combining both analog and digital circuitry. The downside, it that overtime, these SID chips have a tendency to fail, causing the same distorted or dropped audio that I have been experiencing on my machine. In serious cases, the chip fails completely producing no sound whatsoever. Also, unfortunately, these chips have not been produced in decades, so fully functional old-stock SID chips can fetch a handsome prince on eBay. So what is one to do if they desire to keep their beige time machine singing sweet tunes? There are some after market options which can emulate the sound of a classic SID, but they are not perfect in their emulation and they can be a bit pricey as well. While pondering this conundrum it occurred to me that I actually had another Commodore 64 that I had acquired in a lot of used and mostly broken electronics. I decided to roll the dice and do a SID swap to see if the chip from the donor machine would work.

 

The actual process of swapping chips is extremely easy. Just open up the case, locate the chip (the year range of my 2 C64s the SID chip used was a 6581, which is printed on the top of the chip.), pull the chips using a chip puller - which is essentially a large set of tweezers - plug the donor chip into the socket. You want to make sure the chip is align *exactly* as it was when you pulled it from the donor machine. Mine had a dot on the chip which made it easier to see which end should be pointed "up" in the socket. After completely the swap I turned on the 64 and loaded up "Ghostbusters" and to my infinite pleasure I was treated to the entire tune during the opening screen. I then loaded up a new Commodore 64 game called "Galencia" - yes, people are still making software for these old workhorses - and was treated to lush sound dripping with that certain je na sais pas that only a fully functional SID chip can produce. After running "SID Bench", a piece of software that tests all of the registers in the chip for functionality and sound quality, I was off to the races! Luckily, the donor machine had a functioning chip. Fixing stuff is fun!