RAD Expansion Unit for the Commodore 64

For anyone that has known anything about “CubicleNate” for any period of time will know that I am a huge fan of all things Commodore 64. Maybe not everything but most things, I absolutely am. I am also a fan of open source and the communities that have developed around it. When you combine open source and vintage, that makes it all so much more exciting. Which makes me think… I need to build a list of open source vintage tech projects…

Bottom line up front: This is an open source project that leverages Raspberry Pi technology to extend the the Commodore 64 usefulness through two types of RAM expansion, the Commodore REU flavor and the NeoRAM / GeoRAM expansion. This has the capability of providing an accelerated “Turbo mode” but it is not yet included as part of the software download from the Github Project. I see a lot of fantastic capability with this project. I really enjoy the merging of old and new tech where the result is something far more interesting the the devices alone.

What is it?

This is a cartridge port expansion device has some circuitry, buttons and headers to accommodate your choice of Raspberry Pi models, Pi 3A+/3B+ and Zero W 2 models.

This is not a product you can buy from any vendor at this time, you would have to make your own which would require some more advanced soldiering skills as most of the components are surface mount devices.

What this will do for you is give you up to 16 Mbytes of the Commodore style RAM Expansion often called “REU” as well as the 4 Mbytes of NeoRAM / GeoRAM style of expansion that has become more common as of late.

The great thing about the REU is that it will allow you to play some of these newer games that take advantage of it like Sonic the Hedgehog or the PETSCII Robots REU version.

These features of the RAD Expansion are accessed through a menu driven user interface. Here the type of memory expansion can be selected along with a file browser where applications can be selected and run.

Another very interesting feature that the RAD Expansion can do is to play NUVIE movies. I hadn’t heard of these before but they are 16 Mbyte movies that can be run by any Commodore 64 with a 16 Mbyte RAM Expansion Unit.

There is a very informative Review of the RAD Expansion on YouTube that is what brought my attention to this. If such a thing interests you, check out this video and the associated Github project.

RAD Expansion Project on Github

Commodore RAD Expansion Unit Review

It will be interesting to see what else the developer can do with this. I’d like to see some sort of merger with a similar project called the SideKick64 that does just about everything else except for the 16 Mbyte REU function.

Sidekick64 Project on Github

Final Thoughts

Devices like this really get my imagination juiced up and wondering, what else can I do with such a thing? I often think about what it would take to have a kind of all-in-one expansion for the Commodore 64 to give you multiple SIDs, MIDI, faster CPU, more RAM and add some USB, Network and perhaps even some extended video modes. Why? Not sure, it just sounds like a fun thought experiment.

I am hoping to continue to see more things like this. It’s fun to see the work done by incredibly smart people and equally as amazing to see the talent that creates these magnificent projects make it open source. The Commodore 64 is truly in its prime. I am looking forward to what comes next.


RAD Expansion Project on Github
Commodore RAD Expansion Unit Review
Collection of NUVIE movies
Sonic the Hedgehog on TheC64 with SNES Style Gamepad

One thought on “RAD Expansion Unit for the Commodore 64

Leave a Reply