Board pcb

N64 Pico Cart Reader V2

A simple, open-source N64 cartridge reader powered by a Raspberry Pi Pico. Plug it in via USB to dump ROMs and back up saves directly to your computer using a web browser or command line.

Features

• Full ROM dumping for retail N64 cartridges (up to 32 MB)
• Save read/write/restore for all retail save types:
  • SRAM (e.g. 1080 Snowboarding, Ocarina of Time)
  • EEPROM 4K/16K (e.g. GoldenEye, Super Mario 64)
  • FlashRAM (e.g. Majora's Mask, Pokemon Stadium) (For a full list of N64 games and their save types, see Micro-64's Game Save List)
• Controller Pak (MPK) export/import
• GameShark cartridge export/import/restore
• Web Serial GUI — runs in Chrome/Edge, no install required
• Python CLI for all other users
• 3.3V-native design — no level shifting needed, lower BOM cost
• Automatic cart identification — detects game, ROM size, and save type from a built-in catalog

Getting Started

See docs/GETTING_STARTED.md for full setup instructions.

Quick Start

1. Flash the pico_headless_demo.uf2 firmware to your Pico (hold BOOTSEL while plugging in USB, then drag the file onto the drive).
2. Insert an N64 cartridge.
3. Open the Web Serial UI in Chrome or Edge, or use a CLI:

Windows (PowerShell):

./host-tools/powershell/N64CartReader.ps1 -Port COM5

Windows/macOS/Linux (Python):

# example for windows
python3 host-tools/python/pico_pak_n64_magic_cli.py --port /dev/ttyCOM5 n64-cart-id --rescan
# example for linux
python3 host-tools/python/pico_pak_n64_magic_cli.py --port /dev/ttyACM0 n64-cart-id --rescan

Project Layout

firmware/
  rp2040/          C-based firmware for the Raspberry Pi Pico (timing-critical bus logic)
host-tools/
  powershell/      Native CLI for Windows (no setup needed); also supports macOS/Linux
  python/          Cross-platform CLI for validation, diagnostics, and batch scripts
  web/             Easiest, driverless browser-based interface using Web Serial
hardware/
  board/           V2 hardware project (KiCad PCB, schematics, and BOM)
enclosure/
  board/           3D-printable protective case (FreeCAD and STL files)
docs/              Technical guides, hardware documentation, and troubleshooting
LICENSES/          Third-party license texts for shared components

Web Serial UI

The browser-based interface is the easiest way to use the reader. It works in Chrome and Edge via the Web Serial API. No drivers or software installation required.

Open host-tools/web/index.html directly in your browser, click Connect, and the UI will detect your cartridge and present options for ROM dumping, save export/import, and GameShark operations.

See docs/WEB_SERIAL_UI.md for details.

Python CLI

The Python CLI provides full access to all device capabilities and is used for bench testing, validation, and scripted workflows.

cd host-tools/python

# Identify the cartridge
python3 pico_pak_n64_magic_cli.py --port /dev/ttyACM0 n64-cart-id --rescan

# Export a save
python3 pico_pak_n64_magic_cli.py --port /dev/ttyACM0 n64-export --out my_save.bin --sha256

# Import a save with verification
python3 pico_pak_n64_magic_cli.py --port /dev/ttyACM0 n64-import --in my_save.bin --verify

# Dump the full ROM
python3 pico_pak_n64_magic_cli.py --port /dev/ttyACM0 n64-rom-dump --out my_rom.z64

# Run the validation matrix
python3 n64_validation_matrix.py --port /dev/ttyACM0

PowerShell CLI

A native alternative for Windows users (no installation required). Works with the built-in PowerShell 5.1 or PowerShell 7+ (pwsh) on any platform. See Getting Started for Windows execution policy setup.

# Interactive menu (use COMx on Windows, /dev/ttyACM0 on Linux)
./host-tools/powershell/N64CartReader.ps1 -Port COM5

# Export a save
./host-tools/powershell/Export-Save.ps1 -Port COM5 -Out my_save.bin

# Import a save with verification
./host-tools/powershell/Import-Save.ps1 -Port COM5 -In my_save.bin -Verify

# Dump the full ROM
./host-tools/powershell/Dump-Rom.ps1 -Port COM5 -Out my_rom.z64

Building the Firmware

Requires the Pico SDK and CMake.

cd firmware/rp2040
export PICO_SDK_PATH=/path/to/pico-sdk
cmake -S . -B build
cmake --build build -j4 --target pico_headless_demo

Flash with picotool or drag build/pico_headless_demo.uf2 onto the Pico in BOOTSEL mode.

Hardware

The V2 board is a single PCB with an integrated N64 cartridge slot and Raspberry Pi Pico footprint. The design is in KiCad under hardware/board/kicad/.

Power is supplied through USB. The RP2040 runs at 3.3V, which matches N64 cartridge logic levels directly.

Pin mapping and board documentation are in docs/HARDWARE.md.

Troubleshooting

Cartridge not detected or garbled header: Remove the cartridge, clean the edge connector contacts with isopropyl alcohol and a cotton swab, and reseat firmly.

EEPROM save shows type=none after cart swap: Run n64-cart-id --rescan or retry 3-5 times. The Joybus bus needs a moment to settle after a physical swap.

Controller probe returns IO_ERR: EEPROM cartridges and controllers share the same Joybus data line. Unplug one to test the other.

Web Serial won't connect: Web Serial requires Chrome or Edge. Firefox and Safari are not supported. Make sure no other application (terminal, serial monitor) has the port open.

V1 Legacy

The original N64 Cart Reader was built on an Arduino Mega 2560 with an SD card for storage and a serial terminal interface. That design is preserved in the legacy/v1-arduino branch.

See docs/V1_LEGACY.md for details on the original hardware.

Acknowledgements

N64 Pico Cart Reader V2 was designed and implemented by Jayson Gazeley as an RP2040-based successor to the original Arduino N64 Cart Reader.

The project builds on prior open-source preservation work, especially:

• Sanni Cart Reader (GPL-3.0) — foundational N64 cartridge interfacing logic
• drmdmp64_mass / DreamDumper64 by nopjne (BSD-2-Clause) — Joybus PIO and EEPROM reference implementation
• skaman — multi-console cart-reader modules
• hkz & themanbehindthecurtain — FlashRAM command documentation
• Andrew Brown & Peter Den Hartog — N64 controller protocol
• libdragon — N64 controller checksums

See docs/CREDITS_AND_PRIOR_ART.md for full attribution and docs/LICENSING.md for license details.

References

• Joybus Protocol
• N64 Hardware Architecture