The C64 RetroPie Mod

The idea of gutting an original Commodore 64 and replacing the motherboard with a Raspberry Pi is far from new. In fact, I have already done it using an old breadbox case (link). However, during the modding process of that machine the case was completely destroyed and it will not be possible to restore it even if I wanted to 🙁 So when I was asked to do the mod all over again, now with the aid of a case friendly 3D printed conversion kit specifically made for modding a Commodore 64 C case with a RasPi, I immediately accepted! I received the 3D prints a few weeks ago from COREi64.com (link) and instantly made a dedicated post on them as they are very well made (link). The 3D conversion kit costs 65$ plus shipping from Canada and they can be ordered in a variety of colors.

I wanted the machine to look just like an original Commodore 64 C on the outside, but with its internals replaced by a Raspberry Pi 3 Model B and the original C64 power supply unit should be used to run the Raspberry Pi. As a little teaser of what to expect, the final mod ended up looking like this – The C64 RetroPie Mod:

Commodore 64 modded with a Raspberry Pi 3 model B. The machine runs RetroPie with emulators for the Commodore 64. Read about the mod on breadbox64.com.
Commodore 64 modded with a Raspberry Pi 3 model B. The machine runs RetroPie with emulators for the Commodore 64. Read about the mod on breadbox64.com.

Building the Machine:

The components used for making the Commodore 64 RetroPie Mod included an original beige Commodore 64C case, a green 3D printed conversion kit from COREi64.com, a Keyrah V2 from Individual Computers (link), a Neutrik HDMI plug (Neutrik NAHDMI-W-B), a 0.5m HDMI cable, two short USB cables (Type A/Micro B) and the power connector from a broken C64 motherboard.

The C64 RetroPie Mod

Powering the RasPi

I have a few broken Commodore 64 motherboards that I use for spare parts when doing repair jobs. Early on I decided to use the power plug from one of these spare boards for powering the RasPi. This way I did not have to go get one of them ugly wall warts! A Dremel was used to separate the female power plug from the mainboard.

Commodore 64 raspberry pi modification. Power connector from an original C64 motherboard for powering the raspberry pi. read more on breadbox64.com.

As the whole idea of the mod was to keep the Commodore 64 case intact, hereby retaining the option of converting the machine back to its original state, the rear side holes were used for all interface cables. Thus, the ‘Video’ port would accomodate the power inlet.

Commodore 64 raspberry pi modification. Power connector from an original C64 motherboard for powering the raspberry pi. read more on breadbox64.com.

The 3D printed material is a little brittle, so care should be taken when drilling holes. Heat is another issue that should be avoided (who would have thought…). Using a rotary tool will melt the material within seconds  – so be careful!
The C64 RetroPie Mod

The C64 RetroPie Mod

The female power plug is mounted using an original screw terminal in the case bottom. The black self-tapping screws are not included in the conversion kit from COREi64.com – I got them from China real cheap 🙂

Commodore 64 raspberry pi modification. Power connector from an original C64 motherboard for powering the raspberry pi. read more on breadbox64.com.

Two pin headers were soldered into the mounting holes of the removed power switch for easy access to Ground and 5V+. Finally a modified USB cable was used to power the RasPi board through a micro USB plug. The RasPi can run power hungry devices through its USB connections of up to 2.5A, but a power supply of 1.2A will provide ample power to run the Raspberry Pi for most applications. In this context, the C64 power supply can provide 1.7A@5V.  As I only intend to run a keyboard (and a green power LED) through the USB connection (and maybe a game controller) it should suffice. After about 6 hours of continuous use of the Raspberry Pi, the power supply did not even get lukewarm, so I am not too worried about overloading it 😉

The C64 RetroPie Mod

Commodore 64 raspberry pi modification. Power connector from an original C64 motherboard for powering the raspberry pi. read more on breadbox64.com.

HDMI Connection

The HDMI connection from the RasPi went through a Neutrik HDMI plug (Neutrik NAHDMI-W-B). Only the central part of the plug was used.

Commodore 64 modded with a Raspberry Pi. Neutrik HDMI plug (NAHDMI-W-B) used for passing the monitor signal to an external tv. read more on breadbox64.com

Commodore 64 modded with a Raspberry Pi. Neutrik HDMI plug (NAHDMI-W-B) used for passing the monitor signal to an external tv. read more on breadbox64.com

Commodore 64 modded with a Raspberry Pi. Neutrik HDMI plug (NAHDMI-W-B) used for passing the monitor signal to an external tv. read more on breadbox64.com

And look – it fits perfectly into the ‘Serial’ port of the original case without doing any modifications…

The C64 RetroPie Mod

Commodore 64 modded with a Raspberry Pi. Neutrik HDMI plug (NAHDMI-W-B) used for passing the monitor signal to an external tv. read more on breadbox64.com

Finally, some hot glue was used to make sure everything would stay in place. Care was taken that no glue touched the case hereby making it easier to remove everything if I should ever want to convert the machine back to its original state.

The C64 RetroPie Mod

Mounting the Raspberry Pi

Next up was mounting the bracket which holds the Raspberry Pi. The 3D printed conversion kit included some 3D printed washers to keep everything in place – nice detail!

3D prints for the Commodore 64 Raspberry Pi modification. The 3D printed conversion kit makes it easy to do the mod. read more on breabox64.com

3D prints for the Commodore 64 Raspberry Pi modification. The 3D printed conversion kit makes it easy to do the mod. read more on breabox64.com

The kit also includes black oxide screws and some stainless steel washers which makes it very easy to fasten the Raspberry Pi using the brass heat-set inserts.

Commodore 64 raspberry pi 3 model b installed in a C64C case. read the whole build on breadbox64.com

Commodore 64 raspberry pi 3 model b installed in a C64C case. read the whole build on breadbox64.com

The micro SD card of the RasPi can easily be reached from the outside using the small slot in the Cassette port…

3D prints for the Commodore 64 Raspberry Pi modification. The 3D printed conversion kit makes it easy to do the mod. read more on breabox64.com

Keyboard Installation

In order to have the original Commodore 64 keyboard work as a modern USB PC keyboard, a Keyrah V2 was installed. The Keyrah PCB allows connection of classic computer keyboards (like the Commodore 64) to modern computers via USB. It also supports digital joysticks by translating the joystick events to key strokes.

Commodore 64 with a raspberry pi and an Individual Computers Keyrah V2 for connecting the original C64 keyboard to the computer. read more on breadbox64.com

Commodore 64 with a raspberry pi and an Individual Computers Keyrah V2 for connecting the original C64 keyboard to the computer. read more on breadbox64.com

The conversion kit came with a plate that seals off the gap surrounding the USB connection of the Keyrah.

Commodore 64 with a raspberry pi and an Individual Computers Keyrah V2 for connecting the original C64 keyboard to the computer. read more on breadbox64.com

To connect the C64 keyboard internally, four pin headers were soldered into the Keyrah for the USB connection.

Commodore 64 with a raspberry pi and an Individual Computers Keyrah V2 for connecting the original C64 keyboard to the computer. read more on breadbox64.com

Commodore 64 with a raspberry pi and an Individual Computers Keyrah V2 for connecting the original C64 keyboard to the computer. read more on breadbox64.com

The second USB cable was modifed with plugs that fitted the pin headers and connected the keyboard to the RasPi. No drivers need to be installed as everything is plug and play…

The C64 RetroPie Mod

Power LED mod

To finish off the hardware part of the build, a green power LED was made as the cables of the original LED was too short. The LED cable was made based on this post (link)

Commodore 64 LED mod for the raspberry Pi modification. Breadbox64.com.

See the finished machine and a video of the system in action on the next page…

8 comments on “The C64 RetroPie Mod

  1. Hi there. Yes, it can also be done to a breadbox case. However, the dimensions of the 3D printed conversion kit is a little different for that case. At the COREi64.com store (link) look for the ‘Commodore 64 Raspberry Pi Conversion Kit for Breadbin Style 64‘. That version will accommodate the old style C64 case 🙂

  2. Hi, is it possible to share the 3d printer files so I can print myself and attempt this mod?

  3. Hi Robert, I don’t have the 3D printing files 🙂 COREi64, who created the prints, also owns them. But the prints can be purchased on his website or on Ebay.

  4. Hi, I have a pressing question… Is it possible to use real sid-chips (two of them), rather than emulation with a Pi or Odroid?

  5. I’ve seen people play SID tunes using the GPIO on the RaspPi. However, custom drivers were used in order to make it work. So it should be possible, but may include a bit of coding to make it work 🙂

  6. Nice clean look to your mod. I’m aspiring for a similar finished product… Where did you get the panel mounted HDMI port? It seems to fit the C64C’s default hole perfectly. Did you have to modify it to get it flush with the case? Many thanks.

  7. Hi there and thanks! I got mine online – just search for ‘Neutrik NAHDMI-W-B’. Neutrik has retailers worldwide, so it should be quite easy to obtain a copy. The Neutrik HDMI plug does fit perfectly and no modifications were done to make it fit. I just removed the bracket and used some hot glue to make it stay in place. It does not get much easier than that! Good luck with your RasPi-mod 🙂

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