nes-snes-arcade-stick

How the NES & SNES controllers function: https://gamesx.com/wiki/doku.php?id=controls:nes_snes_controller

The link above contains controller port pinouts. Use a multimeter to identify the wires in the extension cable, as they differ by manufacturer.

Bill of Materials

• CD4021 (x2)
• Schottsky diodes (x2)
• SPDT switch (x1)
• 10k resistors (x16)
• Joystick (x1) AliExpress
• Buttons (x8) AliExpress
• NES controller extension cable (x1)
• SNES controller extension cable (x1)

Schematic (KiCad)

Note: the Y button for SNES will be the B button for NES, and the B button for SNES will by the A button for NES.

Stripboard Layout (DIY Layout Creator)

Case (OpenSCAD)