Sven Krasser’s Blog

Musings on technology, security, and sundries.

Assembling my Commodore 64

For this latest part of my series of posts on building a Commodore 64, it is time to assemble all the pieces. The Pixelwizard C64C case has since arrived in the mail, and now all parts (namely the Ultimate 64 board and an original keyboard) need to go into it. To that end, I ordered a mounting kit as well, which contains standoffs for the keyboard and a support for the U64 board. And that’s where the problems start…

The mounting kit I ordered consists of 3D-printed plastic parts. When I took them out of the box, they were severely warped. Presumably, having them tour Los Angeles during summertime inside a package for the better of two weeks did not help matters. After a quick stop by Thingiverse, I downloaded files to print alternative standoffs and another circuit board support using my 3D printer at home. I chopped the latter into two parts in my slicer since my printer bed isn’t large enough. Unfortunately, the design I found didn’t fit my version of the U64 board. A shrouded header was in the way, and a couple of other items didn’t align well either. Since the supports are mainly important when pushing SID chips into the empty sockets to prevent the board from flexing, I’m foregoing adding those for now. The U64 manual has a link to some simpler 3D-printable clips that can serve the same purpose that I’ll try out if the need arises.

The keyboard standoffs worked mostly fine. For the left one, I’m using a washer so the screw can actually hold it in place. For the right one, I had to cut out a small chunk of material so it properly fits over the control port. Also, the keyboard needs to be plugged in before securing the standoff since the standoff is right over the keyboard connector. (This was a nice property of the professionally printed version I had ordered—it doesn’t mount directly over the board.) After securing everything in place, the last two steps are to mount the power/status LED into the top part of the case and to connect it to the board before screwing the case together.

So far, so good. The machine works nicely. Off to try some games. Which brings me to the next problem. The DE-9 connector I’m using for my joystick doesn’t fit into the control port anymore now that the board is in the case. The DE-9 variant used by old joysticks doesn’t have the shields and screws regular DE-9 connectors feature, and the receptacle in the computer is flush with the case (it does not stick out like a regular DE-9 connector). The result is that the parts of the connector backshell that hold the actual metal connector in place get in the way when trying to plug it into the receptacle.

Cutting those away is quickly done, but something else then needs to hold the metal connector in place. Since I don’t use the screw holes, attaching some nuts to the back of the shield would allow me to use a screw through the backshell to hold it in place. Attempt one was to solder nuts onto the shield. That turned out to not work particularly well. The nuts kept coming off with little force, and the solder would not bond well with the nuts. Acknowledging my insufficient soldering skills, it was time to get the big guns out… or rather, the glue gun. Two blobs of hot glue did the trick, and after the nuts were in place, I used them to reattach the backshell with screws. That worked, but the result isn’t great. The connector sits still somewhat loose in the receptacle, and it does not look particularly visually appealing.

I’ve ordered DE-9 extension cords designed for joysticks, and they fit perfectly into the case with their retro joystick style plug while the receptacle at the other end is more forgiving about regular non-joystick DE-9 connectors. In addition, I’ve ordered two cable assemblies similar to the ones used by actual old joysticks. I suspect that these are new old stock (NOS), and I would prefer working with parts that are still in production. The picture above shows the difference between the unmodified DE-9, the modified makeshift one, and a joystick DE-9 (also note how the plug is longer).

Lastly, I’ve bought a copy of Sam’s Journey, released in 2017 for the C64. I’d say they don’t make games like this anymore, but they do—released 35 years after the machine it is running on was first introduced! And if you’re interested in playing it without the hassle of building an 8-bit computer first, the download comes packaged with a preconfigured emulator to run the game on Windows and Linux.