Adding a Right Stick to the Saturn 3D Control Pad — USB Extension Unit XV

Editor’s note: This is an English translation of an article originally published in Japanese in May 2025 (the original Japanese article). For the latest information on the product covered here, see its product page.

I built the Saturn 3D Control Pad USB Extension Unit XV, a USB unit that adds a right stick to the Saturn 3D Control Pad — known in Japan as the Sega “Multi Controller,” or “Marucon.”

With a right stick on the pad, camera control in 3D games becomes much more comfortable, so you can now play a wider range of games on the Saturn 3D Control Pad.

For the original Saturn 3D Control Pad USB Extension Unit Plus, check out this article.

Tindie　

What’s New in the Saturn 3D Control Pad USB Extension Unit XV

Adding a Right Stick

I added a right stick to the Saturn 3D Control Pad USB Extension Unit.

Now you can comfortably play games that need a right stick — for things like camera control — on the Saturn 3D Control Pad.

For the right stick, I used a 5-way micro switch from Alps Alpine, the SKRHAAE010.

This micro switch is a digital-input part with 5 directions (4 directions plus a center push), so you can’t do slow, fine camera movements the way an analog stick can — but it has an upside too: it never suffers from stick drift.

Inner-Color Shell

While adding the right stick, I figured I might as well rethink the design too, so I gave the bottom shell a new design.

Since it’s a right stick, I tried to work its functional role — aiming and shifting your view — into the design.

The circular rim has an inner color in it, so the color shifts depending on your viewing angle — a design that’s only possible with multicolor 3D printing.
Looks great.

Technical Details

The Circuit

Here’s the circuit.

Basically, I wired each input from the micro switch to the spare pins on the PIC microcontroller.

The Board

The Saturn 3D Control Pad USB Extension Unit’s board is pretty small, so finding a spot for the right-stick micro switch was a struggle.

After nudging each part around, I managed to fit everything into a good layout.

Since it’s a right stick, the key was to place it as far toward the right-hand side as possible.
On the Saturn 3D Control Pad USB Extension Unit Plus the extra buttons sat on the left-hand side, so reworking the layout took quite a bit of effort.

Making the Right-Stick Cover

There was no off-the-shelf stick cover that fit the right-stick micro switch, so this time I designed an original stick cover.

Here’s the stick cover I designed.

Printed on a 3D printer and attached, it looks like this.

It’s compact but sized to be easy to operate, and I designed it so your finger doesn’t start to hurt while you’re using it.

It’s a simple, rounded shape, but it’s the result of a lot of prototyping and trial and error.

By the way, the shell went through the same process — many prototypes before it reached its current design.

Test Play

I actually tried out a few 3D games.

With the right stick on board, 3D games are now comfortable to play on the Saturn 3D Control Pad.

Of the ones I played, Zelda: Breath of the Wild was a bit tricky: fine-tuning your aim when shooting the bow took some getting used to.
On top of that, Breath of the Wild is a game that uses the full button layout of an official controller, so there were moments where I simply ran out of buttons and found it a little hard.

Wrapping Up

I think adding the right stick this time has opened up even more possibilities for the Saturn 3D Control Pad.

It’s not an analog stick, so I can’t call it perfect for every game, but I did confirm that it plays comfortably across a lot of titles.

I also sweated the small details, like the stick cover and the refreshed shell design.

I’m planning to release it for sale soon, so stay tuned.
→ It’s now on sale! It’s available on Tindie, which ships worldwide, so you can order it from outside Japan.

Tindie　

I announce launches on X (formerly Twitter), so give me a follow if you’re interested.

フォロワーいっぱい増えたので改めて今まで作ってきたもの紹介

●サターンパッドUSB化基板
●マルコンUSB拡張ユニット
●SFCコントローラーUSB化基板
●マルコン専用スタンド
などなど

これからもますますものづくりで生きていきます🎮 pic.twitter.com/0QSAKuTobs

— たくさん 🐦 GEEKY Fab. (@takusanToIssho) January 12, 2025

That’s it for this time.
Thanks for reading.