• -1) Start by flashing the latest Cart Reader code to the Arduino like shown here.
• 0) Next watch this video
• 1) Now desolder the transistor and the 5V voltage regulator from the Arduino board. Don't skip this step, it's important.
• 2) Solder SMD parts.
• 3) Solder the GBA slot, the switches, the male pin-headers and the female pin-headers for the clock generator and for the mSD and/or full-size SD module.
• 4) Place the SNES spacer underneath the SNES slot and solder it together with the Mega Drive slot and N64 slot. Next solder the two pushbuttons.
• 5) Solder OLED and configure the two OLED solder jumpers depending on whether pin 1 of the OLED is GND or VCC.
• 6) Install the SD spacer using some double-sided sticky tape or hot glue and solder the legs of the LED as shown, be careful not to short anything.
• 7) Solder N64 controller plug.
• 8) Install the Adafruit Clock Generator and the SD module.
• 9) Solder two wires to connect the Arduino to the Cart Reader shield.
• 10) Plug-in the Arduino.
• 11) Screw the backplate and sidewall in place.
• 12) Add the N64 slot sleeve.
• 13) Picture of a soldered Cart Reader PCB (22uF tantalum cap was replaced by 47uF electrolytic since I didn't have the tantalum at hand and a 470uF cap was added between 5V and GND to improve SA-1 compatibility).