input.h File Reference

SNES Controller Input. More...

#include <snes/types.h>

Go to the source code of this file.

Macros
#define	KEY_A   BIT(7)
#define	KEY_B   BIT(15)
#define	KEY_DOWN   BIT(10)
#define	KEY_DPAD   (KEY_UP | KEY_DOWN | KEY_LEFT | KEY_RIGHT)
	All D-pad directions.
#define	KEY_FACE   (KEY_A | KEY_B | KEY_X | KEY_Y)
	All face buttons.
#define	KEY_L   BIT(5)
#define	KEY_LEFT   BIT(9)
#define	KEY_R   BIT(4)
#define	KEY_RIGHT   BIT(8)
#define	KEY_SELECT   BIT(13)
#define	KEY_START   BIT(12)
#define	KEY_UP   BIT(11)
#define	KEY_X   BIT(6)
#define	KEY_Y   BIT(14)
#define	MOUSE_BUTTON_LEFT   0x01
#define	MOUSE_BUTTON_RIGHT   0x02
#define	MOUSE_SENS_HIGH   2
#define	MOUSE_SENS_LOW   0
#define	MOUSE_SENS_MEDIUM   1
#define	padHeld(pad)
#define	padPressed(pad)
#define	SSC_CURSOR   0x4000
#define	SSC_FIRE   0x8000
#define	SSC_NOISE   0x0100
#define	SSC_OFFSCREEN   0x0200
#define	SSC_PAUSE   0x1000
#define	SSC_TURBO   0x2000

Functions
u8	mouseButtonsHeld (u8 port)
	Get currently held mouse buttons.
u8	mouseButtonsPressed (u8 port)
	Get newly pressed mouse buttons this frame.
u8	mouseGetSensitivity (u8 port)
	Get current mouse sensitivity.
s16	mouseGetX (u8 port)
	Get X displacement since last frame.
s16	mouseGetY (u8 port)
	Get Y displacement since last frame.
u8	mouseInit (u8 port)
	Initialize mouse on given port.
u8	mouseIsConnected (u8 port)
	Check if mouse is connected on port.
void	mouseSetSensitivity (u8 port, u8 sensitivity)
	Set mouse sensitivity.
u16	padHeld (u8 pad)
	Get buttons currently held.
u8	padIsConnected (u8 pad)
	Check if controller is connected.
u16	padPressed (u8 pad)
	Get buttons pressed this frame.
u16	padReleased (u8 pad)
	Get buttons released this frame.
u16	scopeButtonsHeld (void)
	Buttons currently down — the same meaning as padHeld() and mouseButtonsHeld().
u16	scopeButtonsPressed (void)
	Get newly pressed buttons this frame.
u16	scopeButtonsRepeat (void)
	Buttons held past the hold delay, re-triggering every repeat delay (see scopeSetRepeatDelay()) — a keyboard-style auto-repeat.
void	scopeCalibrate (void)
	Calibrate aim from a center-screen shot.
u16	scopeGetRawX (void)
	Get raw (uncalibrated) H position from PPU.
u16	scopeGetRawY (void)
	Get raw (uncalibrated) V position from PPU.
u16	scopeGetX (void)
	Get calibration-adjusted H position.
u16	scopeGetY (void)
	Get calibration-adjusted V position.
u8	scopeInit (void)
	Detect Super Scope on port 2.
u8	scopeIsConnected (void)
	Check if Super Scope is connected.
void	scopeSetHoldDelay (u16 frames)
	Set hold delay (frames before hold triggers).
void	scopeSetRepeatDelay (u16 frames)
	Set repeat delay (frames between repeat fires after hold).
u16	scopeSinceShot (void)
	Get frames since last detected shot.

Variables
u16	pad_keys [5]
u16	pad_keysdown [5]
u16	pad_keysold [5]

Detailed Description

SNES Controller Input.

Functions for reading controller input.

Button Constants

Use these constants with padPressed(), padHeld(), etc:

Constant	Button
KEY_A	A button
KEY_B	B button
KEY_X	X button
KEY_Y	Y button
KEY_L	L shoulder
KEY_R	R shoulder
KEY_START	Start
KEY_SELECT	Select
KEY_UP	D-pad up
KEY_DOWN	D-pad down
KEY_LEFT	D-pad left
KEY_RIGHT	D-pad right

Usage

// Check for button press (just pressed this frame)
if (padPressed(0) & KEY_A) {
    playerJump();
}
 
// Check for button held (continuously pressed)
if (padHeld(0) & KEY_RIGHT) {
    playerMoveRight();
}

Author

OpenSNES Team

Copyright

MIT License

Macro Definition Documentation

padHeld

#define padHeld

(

pad

)

Value:

(pad_keys[(pad)])

padPressed

#define padPressed

(

pad

)

Value:

(pad_keysdown[(pad)])

Function Documentation

padHeld()

u16 padHeld

(

u8

pad

)

Get buttons currently held.

Returns all buttons currently being pressed.

Parameters

pad	Controller number: 0 or 1. Indices 2-4 are accepted and always read 0 — the multitap path cannot be armed (KNOWN_LIMITATIONS.md)

Returns

Button mask of held buttons

if (padHeld(0) & KEY_RIGHT) {
    player_x++;
}

See also

Measured frame costs — what this call costs per frame in five real scenes.

padIsConnected()

u8 padIsConnected

(

u8

pad

)

Check if controller is connected.

Parameters

pad	Controller number: 0 or 1. Indices 2-4 are accepted and always read 0 — the multitap path cannot be armed (KNOWN_LIMITATIONS.md)

Returns

1 if a standard pad answered on that port during the last VBlank, 0 otherwise (0xFF for "yes" until 2026-09-22)

The NMI handler reads one serial bit past the 16 of auto-joypad reading: a joypad returns 1s after its 16 bits (anomie's register doc, Joypads), which is how the snesdev-wiki Multitap page detects controllers. A port holding another device (mouse, Super Scope) reads 0: it is not a pad. Valid from the first VBlank after consoleInit() / setScreenOn().

Note

Until 2026-09-26 it answered 1 for an empty port: an empty port and an idle pad both auto-read $0000, and only the 17th bit tells them apart. What an empty port returns there is modelled as 0 by luna, ares and Mesen2; no reference states it and it is not yet measured on a console.

Warning

Reading the serial ports yourself: mask them first. REG_JOYA ($4016) and REG_JOYB ($4017) are whole-byte reads; only bits 0-1 are the port's data lines. On $4017 bits 2-4 are tied and always read 1, bits 5-7 are open bus; on $4016 bits 2-7 are open bus (fullsnes, "Unused bits in ports"; snesdev-wiki, JOYSER1: "D4-2 always 1"). So if (REG_JOYB) is true on every console and every emulator — test REG_JOYB & 1.

padPressed()

u16 padPressed

(

u8

pad

)

Get buttons pressed this frame.

Returns buttons that were just pressed (not held from previous frame).

Parameters

pad	Controller number: 0 or 1. Indices 2-4 are accepted and always read 0 — the multitap path cannot be armed (KNOWN_LIMITATIONS.md)

Returns

Button mask of newly pressed buttons

if (padPressed(0) & KEY_A) {
    // A was just pressed
}

See also

Measured frame costs — what this call costs per frame in five real scenes.

padReleased()

u16 padReleased

(

u8

pad

)

Get buttons released this frame.

Returns buttons that were just released (held last frame, not now).

Parameters

pad	Controller number: 0 or 1. Indices 2-4 are accepted and always read 0 — the multitap path cannot be armed (KNOWN_LIMITATIONS.md)

Returns

Button mask of released buttons

Variable Documentation

pad_keys

u16 pad_keys[5]

extern

Buttons down, per pad (written by the NMI handler)

pad_keysdown

u16 pad_keysdown[5]

extern

Buttons that went down on this frame

pad_keysold

u16 pad_keysold[5]

extern

Buttons down on the previous frame