System Font

During system boot, the system-font is loaded by NS to LINEAR-memory(in the original 0x14000000 vmem region) which always gets allocated at SYSTEM_memregion+0. Due to it being located there, all of this is GPU accessible. The BCFNT is loaded from the font title for the system region into that memory. During loading, the font-data is modified: the magic-num at fontdata+0 is changed from "CFNT" to "CFNU", and all file offsets are converted to addresses in this allocated linearmem. Processes can get the sharedmem_handle+vaddr for mapping the sharedmem for this via APT:GetSharedFont.

With font-data title-version v0 for USA/EUR/JPN, the size of this entire sharedmem is 0x332000-bytes.

Shared mem structure:

Offset	Size	Description
0x0	0x80	Header
0x80	Font data size	The actual font data. There's also unknown data following the original decompressed font data.

Header structure:

Offset	Size	Description
0x0	0x4	Normally value 0x2?
0x4	0x4	Normally value 0x1?
0x8	0x4	Decompressed font data size.
0xC	0x34	Normally all-zero?

Unicode Private Use characters

Some of these characters are used for tutorial message boxes and notifications; they can also be generally used in Mii names, application titles, etc.

Most of these originated in the "icons" tab of the DS's standard software keyboard, and were extensively used in it's firmware UI.

Private Use Area
U+	0	1	2	3	4	5	6	7	8	9	A	B	C	D	E	F
E00x	A button	B button	X button	Y button	L button	R button	D-pad (unmarked)	DS alarm clock	Boxed emoticon :)	Boxed emoticon >(	Boxed emoticon :O	Boxed emoticon -_-	Sun	Cloud	Umbrella	Snowman
E01x	Negative boxed exclamation mark	Negative boxed question mark	Envelope	Cell phone	Thickly-boxed + (touch calibration mark)	Spades	Diamonds	Hearts	Flowers	Right arrow	Left arrow	Up arrow	Down arrow	Circled dot (like "your position" in smartphone maps)	Camera	Crossed-out square
E02x	Spinner up-left	Spinner up	Spinner up-right	Spinner right	Spinner down-right	Spinner down	Spinner down-left	Spinner left	Large cross	Boxed A (Pictochat room)	Boxed B (Pictochat room)	Boxed C (Pictochat room)	Boxed D (Pictochat room)	Negative boxed A (Automatic DS boot)	Negative boxed M (Manual DS boot)	Crossed-out square
E03x	"P" (Pictochat logo)	"I" (Pictochat logo)	"C" (Pictochat logo)	"T" (Pictochat logo)	"H" (Pictochat logo)	"A" (Pictochat logo)	Crossed-out square	Crossed-out square	Crossed-out square	Crossed-out square	Crossed-out square	Crossed-out square	Crossed-out square	Crossed-out square	Boxed negative X (small letter)	Boxed negative X (big bold letter)
E04x	Power button (Wiimote)	D-pad (Wiimote)	A button (Wiimote)	B button (Wiimote)	Home button (Wiimote)	Start button (Wiimote)	Select button (Wiimote)	1 button (Wiimote)	2 button (Wiimote)	Analog stick (Nunchuck)	C button (Nunchuck)	Z button (Nunchuck)	a button (Classic)	b button (Classic)	x button (Classic)	y button (Classic)
E05x	Left analog stick (Classic)	Right analog stick (Classic)	L button (Classic)	R button (Classic)	ZL button (Classic)	ZR button (Classic)	Return (keyboard symbol)	Space (keyboard symbol)	Wii pointer	Wii pointer "1"	Wii pointer "2"	Wii pointer "3"	Wii pointer "4"	Wii pointer dragging	Wii pointer dragging "1"	Wii pointer dragging "2"
E06x	Wii pointer dragging "3"	Wii pointer dragging "4"	Wii pointer panning	Wii pointer panning "1!	Wii pointer panning "2"	Wii pointer panning "3"	Wii pointer panning "4"	Wii logo	Superscripr "er"	Superscript "re"	Superscript "e"	Negative boxed question mark	nothing	nothing	nothing	nothing
E07x	Boxed X	Boxed negative X (Close button)	Back	Home	Steps	Play coin	Video camera	Analog stick (3DS)	Power button (O3DS)	D-pad up	D-pad down	D-pad left	D-pad right	D-pad vertical	D-pad horizontal	nothing

Table courtesy Wikibooks