... modification:set 0 as binary,1 as gray code.4.4 Select to display company LOGO Press F_KEY to display ... nothing to do with the setting of F2. 4.6 Set the mark if F2 is effective Press F_KEY to display FL ... modification:set it as 1, when there is input in F2 pin, it will display the mark “INSPECTION”; Set ... it will display “STOP”; Set it as 4, when there is input in F2 pin, it will display “FIRE”; Set it ...