Sprout open-source motherboard adds Linux, Wi-Fi, streaming to vintage iPods

London-based Certain Things has unveiled Sprout, an open-source hardware and software project that replaces the original motherboard in select iPod models while preserving the stock screen, click wheel, and enclosure. The board adds modern connectivity including Wi-Fi, Bluetooth headphone support, USB-C audio with a HiFi DAC, and music streaming from Spotify and Apple Music, plus casting via AirPlay and Google Cast. Two variants will be offered: Sprout Pico built around the Raspberry Pi RP2350 microcontroller, and Sprout Pi which pairs the RP2350 with a Raspberry Pi Compute Module Zero running Linux for more demanding applications.

The project targets iPod mini 1st/2nd generation, iPod 3rd generation, and iPod 4th generation models, using a microSD card to replace the factory-soldered flash storage. The dual-architecture Sprout Pi offloads audio playback to the RP2350 for power efficiency while running resource-intensive Linux applications including 3D games and OS emulators on the Compute Module Zero. The custom interface recreates the classic iPod navigation experience with click wheel-driven menus, Cover Flow, and even clones of original iPod games, with full schematics, board layouts, firmware, and reverse-engineering documentation published as open source.

Hardware architecture and open-source design

• Dual-architecture compute: Sprout Pi uses the Raspberry Pi RP2350 microcontroller dedicated to audio playback for battery efficiency, while the Raspberry Pi Compute Module Zero handles Linux-based applications including 3D games and OS emulators.
• Storage replacement: The original soldered iPod flash storage is replaced with a microSD card slot, enabling capacity expansion far beyond the original 20GB factory configurations.
• Reverse-engineered peripherals: The project required reverse-engineering the iPod's proprietary display, click wheel, and headphone jack interfaces, with documentation published openly.
• Complete open-source release: Schematics, PCB layouts, firmware, the Sprout Pi runtime software, and reverse-engineering notes are all released as open-source hardware and software.
• Reversible installation: The motherboard swap requires no soldering and is fully reversible, allowing restoration of the original hardware configuration.

Why it matters

Sprout demonstrates a mature model for open-source hardware preservation, combining published schematics with Linux-capable compute modules to extend the lifespan of consumer electronics otherwise abandoned by their manufacturer. For the open hardware community, the project's documented reverse-engineering of Apple's proprietary iPod subsystems provides a reference for similar embedded interface challenges, while the dual-MCU-plus-Linux architecture offers a template for power-sensitive portable devices that occasionally need general-purpose compute.