U50V2&U20V2 reset factory
1.reset whole system,step as follow
- turn off device
- press the reset button and turn on the device,release the reset button after about 6-8s until the sys led goes on
- wait about 8mintues,system will bootup again smoothly if it is correct
2.reset only application
- device is on working status,and sys indicator is blinking once per second
- press Reset button about 6s-8s,then relese and it will recovery application,
- but usually we didnt use this ,and prefer to reset from GUI