HID Shared Memory

This page describes the format of the HID shared memory.

The data for each of the below entries(PAD state, circle-pad, touch-screen, etc) is originally read by the HID module at different times per frame.

size: 0x2b0 (FIRM 4.4)

Offset 0x0

Relative offset	Description
0x1C	PAD state. Bit set = button pressed, bit clear = button not pressed.
0x28	Second PAD state entry.
0x34	This stores circle-pad info: the low s16 is the X coordinate, the high s16 is the Y coordinate. The circle-pad center is ~0 for these fields. The range for these fields is approximately: -0x9C(bottom/left) - 0x9C(top/right).
0x38	Third PAD state entry.
0x44	Second circle-pad info entry.
0x48	Fourth PAD state entry.
0x54	Third circle-pad info entry.
0x58	Fifth PAD state entry.
0x64	Fourth circle-pad info entry.
0x68	Sixth PAD state entry.
0x74	Fifth circle-pad info entry.
0x78	Seventh PAD state entry.
0x84	Sixth circle-pad info entry.
0x88	Eighth PAD state entry.
0x94	Seventh circle-pad info entry.
0x98	Ninth PAD state entry.
0xB8	first used entry number in the touch-screen position info buffer?

Offset 0xC0

This 0x48-byte region stores entries for touch-screen position info. Each entry is 0x8-bytes, there's a total of 9 entries. When the touch-screen is not being touched, this region is all-zero.

The last 8 entries contain the pixel coordinates, while the first entry seems to contain the raw coordinate data prior to being converted to pixel coordinates.

Entry format

Relative offset	Size	Description
0x0	0x2	X coordinate.
0x2	0x2	Y coordinate.
0x4	0x4	This is 0x0 when this entry doesn't contain any actual data, value 0x1 indicates that this entry contains actual data.