Antminer AMLOGIC Control Board Firmware Unlocking Kit

A two-piece kit for Antminer S19 and S21-series miners whose AMLOGIC control boards were locked by Bitmain from March 2024. Connected to the control board's micro-USB port, it writes an older Antminer S19k Pro firmware to the board. The board can then take aftermarket firmware: LuxOS (via Commander), Braiins OS (via BOS Toolbox) or Vnish (via Hashcore).

Compatibility

• Antminer S19 and S21-series miners with AMLOGIC control boards
• Does not work on miners running Bitmain firmware released after September 2025 (see Notes)

Specifications

• Contents: OTG micro-USB cable; USB stick with older Antminer S19k Pro firmware
• Connection: micro-USB port on the control board

Notes

• Unlocking procedure: power the miner off, plug the micro-USB end of the OTG cable into the control board, power the miner on and wait for the board's LED to turn solid green, then power off and remove the cable.
• Bitmain firmware released in September 2025 blocks the micro-USB port the kit uses, so the kit cannot unlock miners already running that firmware or later.
• Installing aftermarket firmware after unlocking can still be difficult.