Controllers, GameCube Adapters & Keyboard Setup

8-player SDL3, XInput & native GameCube controller support

OpenSmash-Ultimate supports up to 8 simultaneous players across GameCube controllers, Nintendo Switch Pro Controllers, Sony DualSense / DualShock 4, Xbox Wireless Controllers, 2.4 GHz Hall/TMR pads, fightsticks, and keyboard. Press F2 during play or open Esc → Controllers to inspect every detected device, player slot, and GUID.

• Automatic hot-plug slot memory: Each controller that connects claims the next open player slot; unplugging and reconnecting restores the exact same player number.
• Positional vs printed-label buttons: By default (layout = positional), face buttons follow the physical Nintendo Switch diamond (right button = A, bottom button = B). If you prefer Xbox printed letters, switch Layout to labels in Esc → Controllers.
• Ensure SDL3.dll is present: Without SDL3.dll beside build\ssbu.exe, Windows falls back to XInput only (Xbox pads in slots 1–4). Both OpenSmash-Setup.exe and Install WindowSmash.bat install SDL3 automatically.

GameCube controller & 4-port USB adapter setup

Competitive Smash players can use original GameCube controllers with native octagonal gate coordinates, true analog L/R shoulder travel, dedicated Z macro behavior, and in-game Options → Controls → GameCube Controller profiles:

1. Nintendo Wii U / Switch USB Adapter or Mayflash 4-Port GameCube Controller USB Adapter: Slide the hardware switch on the adapter to Wii U (not PC) for native 4-port direct polling. Unlike emulators that force a driver swap, OpenSmash works with both Windows’ built-in HID driver and the WinUSB driver installed by Zadig for Dolphin. Plug in the second (grey) USB cable as well to enable controller rumble. (Third-party adapters switched to PC mode also work as standard SDL pads.)
2. Nintendo Switch 2 USB GameCube Controller (USB cable only; Bluetooth unsupported): This pad requires an initialization handshake on USB Interface 1. If build\play.log reports its interface 1 has no WinUSB driver, open Zadig, choose Options → List All Devices, select Interface 1 (USB ID 057E 2073 01: do not replace Interface 0!), and install WinUSB. On restart, play.log confirms Switch 2 GameCube controller started.
3. Apple silicon macOS GameCube adapters: Enable GCAdapterDriver and install libusb (brew install libusb) with the adapter set to Wii U mode.
4. Give any standard pad GameCube controls: Set style = gamecube under [device xboxone] or [device ps5] in config\controllers.ini to map triggers to L/R and bumpers to Z.

Default keyboard bindings, Shift walk & Super Smash Flash 2 mode

Keyboard defaults to Player 1 alongside Pad 1 (set keyboard_player = 0 in config\controllers.ini if you want Player 1 exclusively on a controller and Player 2 on another):

Because digital keys push the virtual stick to 100% immediately, holding Shift (WALK) scales stick tilt partway so you can walk, perform forward/up/down tilts without smashing, and crouch on platforms without dropping through. Alternatively, added in PR #126 (v0.3.0-alpha.2), setting movement = ssf2 under [keyboard] enables Super Smash Flash 2 tap-to-walk, double-tap-to-dash, and tap-Up short-hop logic.

Advanced config/controllers.ini customization

Open config\controllers.ini from Esc → Controllers → Open controllers.ini to configure per-device sections ([device default], [device ps5], [device switchpro], [device gamecube], or specific GUIDs):

[general]
keyboard_player = 0
background = 1

[device default]
layout = positional

[device ps5]
rumble = 60

[keyboard]
movement = ssf2
LSTICK_LEFT = A
LSTICK_UP = W
LSTICK_RIGHT = D
LSTICK_DOWN = S
X = Space
L = Shift
R = Ctrl
ZR = E

Steam Input & Big Picture launch parameters

To launch a Windows build directly through Steam Input for exotic controllers, add "C:\OpenSmash\build\ssbu.exe" as a Non-Steam Game, set Start In to "C:\OpenSmash", and set Launch Options to dump\modules --status 30 --online (omit --online for offline play).