I’m a big fan of Retropie – an operating system for Raspberry Pi computers that contains a multitude of emulators for classic game systems. This allows for a multitude of homemade and retro games to be played on any display with an HDMI input.
I grew up with the Sega Master System II as my first console. It was an 8-bit console in a 16-bit era, and Sonic the Hedgehog was my first console game. Now, this wasn’t the famous Genesis/Mega Drive game that really launched Sonic into the mainstream but was similar enough that it was a great game in itself. It was also the game that loaded when I didn’t put a cartridge, so I played many, many hours of it. This story is actually also true of my fiancée, and we were each surprised to find we had it in common.
As such, my Retropie has pride of place in our TV stand. Unfortunately, it’s in an ugly little plastic case with a momentary switch I soldered on and a pathetic 30mm fan that just seems to draw power and not really keep it cool.

In order to make it a little more appropriate for the TV stand, I want to gut the insides of a Master System II console, modify the case to accept modern-day inputs, and mount the Raspberry Pi inside. This would make it a console worthy of sharing space with my modern black boxes.
So I bought a Master System II secondhand (my fiancée was not going to let me destroy hers) and got to planning my build.
Opening the Black Box

Holding it in my hands again after so many years, I was surprised to find how incredibly light the Master System II is. Once I opened it up, I understand why. After removing 5 external screws I was greeted with a sheet of metal covering the interesting bits. A few more screws and the brain of the system is revealed:

But I don’t want any of that! No cartridge socket, no old controller ports, no inputs or outputs – I want just the shell. Luckily, a few more screws and…

Without the board and protection inside, it’s surprising how cavernous it is. Perfect for doing this:

This tiny little Raspberry Pi board has so much more power than the console it’ll imitate. Now, if I wanted to be simple and ugly I would route the power, HDMI, and controller cables through the open cartridge slot on the top and be done with it.
But instead, I’m going to buy a coping saw, some files, and a bunch of cable extenders and make it as convenient as my Xbox One to setup.
Jack it up
I am currently using a Raspberry Pi 3B, but I hope to upgrade to a 4B when I have the spare cash. As such, I’m planning to have ports that suit both boards. Including:
- A USB 3.0 Type-C power jack
- A full-size HDMI port
- An RJ45 Ethernet port
- A MicroSD card extender
- A 4-pole 3.5mm audio port
- 2x USB 3.0 Type-A ports at the rear for a Logitech Unifying Receiver and for later expansion
- 2x USB 2.0 Type-A ports at the front for controllers
I want to have more than just a standard female-to-male cable for these ports though, I want to have the female ends mounted securely to the case with cutouts so I can plug and unplug the system easily.
Adapting it to upgrade the Raspberry Pi board
For my current board, the USB 3.0 Type-A ports are overkill but will work with the RP3 USB 2.0 ports just fine. However, in order to use the Type-C power jack, I’ll need to use a Type-C to MicroUSB adapter and remove it when I eventually upgrade.
Conversely, when I get the RP4 I will need to add a Micro HDMI to HDMI adapter inside when I swap the boards out – but that’ll help since otherwise, I’d need to use the same adapter on the outside to plug it into the TV anyway.
Next Step
The next step is to buy the cables I need! I’ve ordered some extensions from AliExpress and once they arrive I’ll cut out holes in the backplate of the Master System shell and screw/glue them in.
Once everything arrives I’ll make an update post and let you all know how it goes.