... F,L,E,0,1,2,3,4,5,6,7,8,9 “Black”), can randomly be one among them ... 6,7,8,9 “Black”)as displaying contents of the high digit of the LCD;then press F_KEY button to switch to low ... LCD.4.2 Factory default:Press F_KEY button to display FL, and 00 blinks at the same time,press C_KEY to increase to 32 ... This set value will have nothing to do with the setting of F1. 4.7 Exit of programming Keep pressing F_KEY ...