1、Prepare ARM board programming
Computer install “One-click install Android driver”first.
Connect the Android cable to ARM board and computer.
Press and hold the PWR button on the ARM board and power on system same time. After 7s, release the PWR button.
Double-click"(L0-H-1.0.001) storage file" and click "点我_烧写存储文件.bat".
System restart, Don't do anything during this period until it is automatically turned off.
After restarting system, select the app below, click ALWAYS, and enter the application system.
Enter the password, to the application setting interface, set the volume to the maximum, click the OK button,
return to the working interface, and turn off the machine.
2、Main board System Programming

Under the shutdown state, the main board is connected to the offline Downloader.
Note the 3.3V interface on the system main board corresponds to the 3.3V interface of the offline Downloader.
Open the system, press the button on the offline Downloader, after the red light flashes, the blue light is always bright,
the system main board software upgrade is completed, turn off, and restart.
3、Handpiece programming
Power-off, disassemble the case of the handpiece, and connect the handpiece main board to the offline Downloader.
Note the 3.3V interface on the handpiece main board corresponds to the 3.3V nterface of the offline Downloader. 
Power on system and handpiece, press the button on the offline Downlaoder, after the red light of the it flashes,
the blue light is always on, the software of the handpiece is finished, shut down system and restart.