Saturn 3D Control Pad USB Extension Unit XV

This is an extension unit that turns the Sega Saturn 3D Control Pad (aka the Sega “Multi Controller” or “Marucon” (マルコン) in Japan) into a USB device.
In one step, your Saturn 3D Control Pad becomes usable as a USB gamepad.

The XV comes with a right stick.
The right stick is digital 4-way plus center push.

The USB connector is Type-C.

TOC

Where to Buy

Kaden no Ken-chan 
GEEKY Fab. BOOTH Shop 

If you’re outside Japan, you can still order from BOOTH through its overseas forwarding services (Buyee / tenso.com).

Demo (Standard Version)

Features

Turn Your Saturn 3D Control Pad into USB in One Step

By swapping the standard unit for this product, your Saturn 3D Control Pad becomes usable as a USB gamepad.

Please connect the USB cable while this product is attached to the Saturn 3D Control Pad.
If you connect this product to a PC or similar with a USB cable while it is not attached to the Saturn 3D Control Pad, it will start up in firmware flashing mode.

Right Stick on the Back of the Unit

We added a right stick to the Marucon USB Extension Unit.
Now you can comfortably play games that need a right stick—such as ones with camera control—on the Saturn 3D Control Pad.

Because this microswitch is a 5-way (4-way plus center push) digital input, you can’t do slow camera movements the way an analog stick can, but it also has the upside that stick drift never happens.

Supports the Mode Switch

It supports the mode switch on the Saturn 3D Control Pad itself.
The button assignments in + mode / 〇 mode are as follows (with the standard firmware).

3D Control Pad Button+ Mode〇 Mode
A11
B22
C33
X44
Y55
Z66
L7L Trigger (Z axis)
R8R Trigger (Z rotation axis)
start99
Analog stickNot activeLeft stick (X axis / Y axis)
D-padHat switchHat switch
Back-of-unit stickRight stick (X/Y rotation axis)Right stick (X/Y rotation axis)
Back-of-unit stick press1212

Freely Rewritable Firmware

The firmware source code is published as open source.
https://github.com/takusan213/usb-ss3d-gamepad

Firmware can be flashed over USB.
By connecting this product to a PC while it is not plugged into the Saturn 3D Control Pad, it starts up in firmware flashing mode.

Product Photos

Verified OS / Consoles

  • Retro Freak
  • Windows10
  • Windows11
  • Raspberry PI 3
    • Raspberry Pi OS
    • Recalbox for RASPBERRY PI 3
    • RetroPi 4.7.1 for RASPBERRY PI 2/3
  • Raspberry PI 4
    • Raspberry Pi OS
    • Recalbox for RASPBERRY PI 4/400
    • RetroPi 4.7.1 for RASPBERRY PI 4/400
  • switch (requires flashing the firmware listed at the end of this article)

Consoles Reported Working by Users

The following consoles have been reported as working by our users.

  • POLYMEGA
    • Requires flashing the Xinput firmware (the firmware is listed at the end of this article)
    • Turning on the analog setting in the in-game controller settings makes the analog stick work

About Controller Settings on Steam

If you use it on Steam with the standard firmware, please configure it from Big Picture mode.
If the controller isn’t recognized in Big Picture mode, open Steam’s Settings → Controller → General Controller Settings, select “SS3D Gamepad,” and assign the buttons.

If you use the xinput firmware, the above setup isn’t needed.

About Flashing Firmware

Web Tool for Flashing Firmware

We provide a firmware flashing tool.
You can use it with no installation required.

Try the firmware flashing tool

See this page for how to use it.

List of Released Firmware

You can find the latest firmware on the page below.

Latest Firmware List

Below are descriptions of each firmware.

Original Firmware

This is the firmware flashed at the time of purchase.
It works as a DirectInput gamepad.
It supports the button mapping tool.

ABXY Swap Function

By holding the start button and D-pad up for one second or more, you can swap the button assignments of A and B, and X and Y.

Xinput Version

This is a version that supports Xinput.

Button Assignments

3D Control Pad Button+ Mode〇 Mode
AAA
BBB
CR1R1
XXX
YYY
ZL1L1
LLeft stick pressL Trigger
RRight stick pressR Trigger
startstartstart
Analog stickNot activeLeft stick
D-padD-padD-pad
Back-of-unit stickRight stick Right stick
Back-of-unit stick pressbackback

ABXY Swap Function

By holding the start button and D-pad up for one second or more, you can swap the button assignments of A and B, and X and Y.

LR / CZ Swap Function

By holding the start button and D-pad down for one second or more, you can swap the button assignments of L and Z, and R and C.

D-pad Switch Function

By holding the start button and D-pad left for one second or more, you can switch the D-pad’s function from “D-pad” to “right stick.”

To summarize the functions:

Button Combo (Hold)Function
start + ↑AB / XY swap
start + ↓LR / CZ swap
start + ←D-pad mode change

Switch Version

This is a version that supports the Switch.
It supports the button mapping tool.

Button Assignments

3D Control Pad Button+ Mode〇 Mode
AAA
BBB
CRR
XXX
YYY
ZZZ
LZLZL
RZRZR
startplusplus
Analog stickNot activeLeft stick
D-padD-padD-pad
Back-of-unit stickRight stickRight stick
Back-of-unit stick pressminusminus

ABXY Swap Function

By holding the start button and D-pad up for one second or more, you can swap the button assignments of A and B, and X and Y.

LR / CZ Swap Function

By holding the start button and D-pad down for one second or more, you can swap the button assignments of L and Z, and R and C.

D-pad Switch Function

By holding the start button and D-pad left for one second or more, you can switch the D-pad’s function from “D-pad” to “right stick.”

To summarize the functions:

Button Combo (Hold)Function
start + ↑AB / XY swap
start + ↓LR / CZ swap
start + ←D-pad mode change

Firmware Release History

Release VersionSummary
v.1.0.0Initial release
v.1.1.0Added ABXY swap function
v.2.0.0Added support for the Plus version (the version with buttons added on the back of the unit)
v.3.0.0Added XV support
v.4.0.0Added mapping tool support

Xinput Firmware Release History

Release VersionSummary
v.xin.1.0.0Initial release
v.xin.1.1.0– Added ABXY swap function
– Added analog stick mode switch function
v.xin.1.2.0Changed the analog stick switch function to a D-pad switch function
v.xin.1.3.0– Swapped the assignments of C/Z and the L/R buttons in + mode
– Added LR / CZ swap function
v.xin.2.0.0Added support for the Plus version (the version with buttons added on the back of the unit)
v.xin.2.0.1Fixed a bug where the ABXY swap function was on by default
v.xin.3.0.0Added XV support

Switch Firmware Release History

Release VersionSummary
v.switch.1.0.0Initial release
v.switch.1.1.0Added LR / CZ swap function
v.switch.1.2.0– Changed so that in + mode, C, Y, Z are assigned to select, capture, home
– Changed the analog stick mode switch function to a D-pad mode switch function
v.switch.2.0.0Added support for the Plus version (the version with buttons added on the back of the unit)
v.switch.3.0.0Added XV support
v.switch.4.0.0Added mapping tool support

Build Log

TOC