Libre Board

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Why Libre Board ​

A control board decides what a miner is allowed to be. Closed boards keep the firmware, the display, the network, and the hashboard connector inside one vendor's machine. Libre Board publishes that layer.

The motherboard ​

Libre Board is the motherboard of a miner. It takes 12–24 V DC, runs a full Linux system on a swappable compute module, and brings the I/O out to documented connectors: Ethernet, the CM5's Wi-Fi and Bluetooth, HDMI, a MIPI camera or display, NVMe, a Raspberry Pi HAT header, Qwiic, fan headers, and USB-C for the hashboards.

The current module is a Raspberry Pi CM5, on two standard 100-pin connectors. The same connectors are how another module would fit. Trying ARM, x86, and RISC-V modules is a design goal. The board in the repository is drawn and tested around the CM5.

Run it, or cut it down ​

Libre Board is a reference design and a board you can run as-is. The KiCad project, the bill of materials, and the fabrication files are published under CERN-OHL-S-2.0. Build that board. Or delete the parts you do not need and change the outline. The license is what makes the second path allowed.

The rest of the stack ​

Libre Board is one layer of the 256 Foundation open mining stack.

  • Ember One is the hashboard. It connects over the USB 2.0 Type-C ports.
  • Mujina is the mining firmware. It runs on the compute module.
  • Hydrapool is pool software. A local pool can run on the same Linux system as the firmware, because the board is a computer and not only a mining controller.

Specifications is the connector list. Where Libre Board is today is the state of Revision 3. Design goals is the work after that.

See also ​