Use the SNES/NES controllers: Difference between revisions
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(→Usage: fixed the NES example code externally linked and added the 2x core delays when triggering in the text examples on this wiki page) |
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<pre> | <pre> | ||
POKE(PAD_CTRL, 0b10000001); //trigger, nes mode, enabled | POKE(PAD_CTRL, 0b10000001); //trigger, nes mode, enabled | ||
ASM("NOP"); //a necessary delay with the 2x speed core | |||
ASM("NOP"); //a necessary delay with the 2x speed core | |||
POKE(PAD_CTRL, 0b00000001); //clear trigger | POKE(PAD_CTRL, 0b00000001); //clear trigger | ||
while((PEEK(PAD_STAT) & 0x40) == 0) //loop while this bit is cleared | while((PEEK(PAD_STAT) & 0x40) == 0) //loop while this bit is cleared | ||
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<pre> | <pre> | ||
POKE(PAD_CTRL, 0b10000101); //trigger, snes mode, enabled | POKE(PAD_CTRL, 0b10000101); //trigger, snes mode, enabled | ||
ASM("NOP"); //a necessary delay with the 2x speed core | |||
ASM("NOP"); //a necessary delay with the 2x speed core | |||
POKE(PAD_CTRL, 0b00000101); //clear trigger | POKE(PAD_CTRL, 0b00000101); //clear trigger | ||
while((PEEK(PAD_STAT) & 0x40) == 0) //loop while this bit is cleared | while((PEEK(PAD_STAT) & 0x40) == 0) //loop while this bit is cleared | ||
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//NES section | //NES section | ||
POKE(PAD_CTRL, 0b10000001); //trigger, nes mode, enabled | POKE(PAD_CTRL, 0b10000001); //trigger, nes mode, enabled | ||
ASM("NOP"); //a necessary delay with the 2x speed core | |||
ASM("NOP"); //a necessary delay with the 2x speed core | |||
POKE(PAD_CTRL, 0b00000001); //clear trigger | POKE(PAD_CTRL, 0b00000001); //clear trigger | ||
while((PEEK(PAD_STAT) & 0x40) == 0) //loop while this bit is cleared | while((PEEK(PAD_STAT) & 0x40) == 0) //loop while this bit is cleared | ||
| Line 351: | Line 357: | ||
//SNES section | //SNES section | ||
POKE(PAD_CTRL, 0b10000101); //trigger, snes mode, enabled | POKE(PAD_CTRL, 0b10000101); //trigger, snes mode, enabled | ||
ASM("NOP"); //a necessary delay with the 2x speed core | |||
ASM("NOP"); //a necessary delay with the 2x speed core | |||
POKE(PAD_CTRL, 0b00000101); //clear trigger | POKE(PAD_CTRL, 0b00000101); //clear trigger | ||
while((PEEK(PAD_STAT) & 0x40) == 0) //loop while this bit is cleared | while((PEEK(PAD_STAT) & 0x40) == 0) //loop while this bit is cleared | ||
Revision as of 14:50, 13 January 2026
NES and SNES controllers
The F256 machines can use these controllers provided they are equipped with an optional FNX4N4S breakout adapter.
The official gamepads of yesteryear work without issue with this and are plentiful in the used market.
Third party modern recreations are sometimes flaky or not working at all. Share you discoveries in the discord!
Super famicom gamepads work very well as substitute for regular SNES gamepads.
Registers
| Register Name | R/W | Address | NES/SNES | Description |
|---|---|---|---|---|
| PAD_CTRL | W | 0xD880 | both | Used to trigger a reading and setting the NES/SNES mode |
| PAD_STAT | R | 0xD880 | both | Used to verify if the triggered polling of gamepad state is done yet |
| PAD0 | R | 0xD884 | both | Buttons statuses: if cleared, they are pressed. If set, they are unpressed. |
| PAD0_S | R | 0xD885 | SNES | Same deal; unused by NES. Consult button table below |
| PAD1 | R | 0xD886 | both | Buttons statuses: if cleared, they are pressed. If set, they are unpressed. |
| PAD1_S | R | 0xD887 | SNES | Same deal; unused by NES. Consult button table below |
| PAD2 | R | 0xD888 | both | Buttons statuses: if cleared, they are pressed. If set, they are unpressed. |
| PAD2_S | R | 0xD889 | SNES | Same deal; unused by NES. Consult button table below |
| PAD3 | R | 0xD88A | both | Buttons statuses: if cleared, they are pressed. If set, they are unpressed. |
| PAD3_S | R | 0xD88B | SNES | Same deal; unused by NES. Consult button table below |
Control register
| Register Name | R/W | Address | Bit7 | Bit6 | Bit5 | Bit4 | Bit3 | Bit2 | Bit1 | Bit0 |
|---|---|---|---|---|---|---|---|---|---|---|
| PAD_CTRL | W | 0xD880 | NES_TRIG | - | - | - | - | MODE | - | EN |
| PAD_STAT | R | 0xD880 | NES_TRIG | DONE | - | - | - | MODE | - | EN |
Control register bit states:
| Bit Name | If set to 1 | If cleared to 0 |
|---|---|---|
| NES_TRIG | Launches the polling of the states of all buttons | Stops polling the states of all buttons |
| DONE | The states of the buttons are ready to be read | The states of the buttons are not ready |
| MODE | SNES data will be used to populate the PAD registers | NES data will be used to populate the PAD registers |
| EN | Enables the gamepads | Disables the gamepads |
Button table
| MODE | NES/SNES | Address | Pad | Bit7 | Bit6 | Bit5 | Bit4 | Bit3 | Bit2 | Bit1 | Bit0 |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 0 | NES | 0xD884 | 0 | A | B | Select | Start | Up | Down | Left | Right |
| 0 | NES | 0xD886 | 1 | A | B | Select | Start | Up | Down | Left | Right |
| 0 | NES | 0xD888 | 2 | A | B | Select | Start | Up | Down | Left | Right |
| 0 | NES | 0xD88A | 3 | A | B | Select | Start | Up | Down | Left | Right |
| 1 | SNES | 0xD884 | 0 | B | Y | Select | Start | Up | Down | Left | Right |
| 1 | SNES | 0xD885 | 0 | A | X | L | R | ||||
| 1 | SNES | 0xD886 | 1 | B | Y | Select | Start | Up | Down | Left | Right |
| 1 | SNES | 0xD887 | 1 | A | X | L | R | ||||
| 1 | SNES | 0xD888 | 2 | B | Y | Select | Start | Up | Down | Left | Right |
| 1 | SNES | 0xD889 | 2 | A | X | L | R | ||||
| 1 | SNES | 0xD88A | 3 | B | Y | Select | Start | Up | Down | Left | Right |
| 1 | SNES | 0xD88B | 3 | A | X | L | R |
Note: L refers to the left shoulder button and R refers to the right shoulder button.
Usage
Example 1: polling a NES controller in PAD0 position and checking if A is pressed:
POKE(PAD_CTRL, 0b10000001); //trigger, nes mode, enabled
ASM("NOP"); //a necessary delay with the 2x speed core
ASM("NOP"); //a necessary delay with the 2x speed core
POKE(PAD_CTRL, 0b00000001); //clear trigger
while((PEEK(PAD_STAT) & 0x40) == 0) //loop while this bit is cleared
;
if((PEEK(PAD0) & 0x80) == 0) reactToAPressed();
Example 2: polling a SNES controller in PAD2 position and checking if X is pressed:
POKE(PAD_CTRL, 0b10000101); //trigger, snes mode, enabled
ASM("NOP"); //a necessary delay with the 2x speed core
ASM("NOP"); //a necessary delay with the 2x speed core
POKE(PAD_CTRL, 0b00000101); //clear trigger
while((PEEK(PAD_STAT) & 0x40) == 0) //loop while this bit is cleared
;
if((PEEK(PAD2_S) & 0x04) == 0) reactToXPressed();
Example 3: polling both types of controller in rapid succession (allows the usage of all 8 controllers!)
//NES section
POKE(PAD_CTRL, 0b10000001); //trigger, nes mode, enabled
ASM("NOP"); //a necessary delay with the 2x speed core
ASM("NOP"); //a necessary delay with the 2x speed core
POKE(PAD_CTRL, 0b00000001); //clear trigger
while((PEEK(PAD_STAT) & 0x40) == 0) //loop while this bit is cleared
;
//section where reactions are made to the various NES presses
//SNES section
POKE(PAD_CTRL, 0b10000101); //trigger, snes mode, enabled
ASM("NOP"); //a necessary delay with the 2x speed core
ASM("NOP"); //a necessary delay with the 2x speed core
POKE(PAD_CTRL, 0b00000101); //clear trigger
while((PEEK(PAD_STAT) & 0x40) == 0) //loop while this bit is cleared
;
//section where reactions are made to the various SNES presses
Source code example in C:
Check out this simple example displaying the statuses of all 4 NES pads on screen, using hex: https://github.com/Mu0n/F256KsimpleCdoodles/tree/main/NES/src
