Avidyne IFD540 Pilot's Manual page 141

User Option Item Title
Bezel Mode
Bezel Backlight
Display Mode
AUX Pages 4-33
Description
Auto* - the bezel backlighting
will rely on the ambient light
sensor in the bezel until a low
threshold is reached, at which
time it uses the dimming bus;
DimBus – the bezel
backlighting will only be
responsive to the cockpit
dimming bus control;
User Control – the bezel
backlighting is completely
controlled by you using the
bottom right IFD knob.
A brightness bar that
represents the bezel brightness
setting when User Control is
selected. This item has no
default value.
Auto* - the LCD display
backlighting will rely on the
ambient light sensor in the
bezel until a low threshold is
reached, at which time it uses
the dimming bus;
DimBus – the LCD display
backlighting will only be
responsive to the cockpit
dimming bus control;
User Control – the LCD display
backlighting is completely
controlled by you using the
bottom right IFD knob.