The GP-BMK-25 will go into a sleep mode if the battery current drops below a certain level. To “wake” the GP-BMK-25 from this mode, press any key. The GP-BMK-25 screen will automatically wake once the battery starts charging or
discharging TURN OFF BACKLIGHT.
While charging the battery, the LCD screen's backlight will slowly flash. To
turn off the backlight, long press << to turn off the backlight, long press <<
again to wake up the backlight.