The AvalonMiner A9 series hash board maintenance course tutorial mainly explains the working principle of the hash board and the troubleshooting method of specific faults. Easy-to-understand courses can help you quickly understand the principles and maintenance ideas. The specific courses include the powering process of the A921 hash board, the transmission direction of the signals, the demonstration of the voltage test point, etc. The combination of theoretical courses and operation exercises can make it easy for you to learn. Quick to master. The Avalon online course launched by ZMRC can help newbies become ASIC Avalon repair masters.