Avidyne IFD540 Pilot's Manual page 127

The center of the page will display the datablock options list for
that given slot. Those items that are displayed in bright green
text can be selected for the given slot. Those items that are
displayed in subdued grey text are not selectable for that slot –
the typical reason is that there is not enough space for the item
given the content above and/or below the slot.
Restoring factory defaults is accomplished by pressing the bottom
right IFD knob and then accepting the Confirm dialog box.
Potential datablock selections are listed below (factory defaults
identified by asterisks). The format of many of the blocks
changes if they are selected to be displayed along the top
datastrip.
Datablock Item Title
and Image
Primary Com/VLOC
(Note: This selection is
permanently greyed out
and is not actually
selectable)
VLOC Radio
Com/Nav Standby #2
AUX Pages 4-19
Defines the position of the top two
datablocks along the left side. These
are permanently dedicated to
Com/VLOC control and display.
Provides a means to display the Active
and #1 Standby Nav frequencies in
slots 3 and 4 (2 lines)
Provides a means to display a 3rd com
or nav frequency (2nd standby slot) (2
lines)
Only available on left side datablocks
Note: If this field is currently in
datablock edit mode as indicated by a
blue background, then com/nav tuning
Content