[Deji]

Native Button ID's

2nd param of 00E1. It's so much easier when you use the PS2 button name, since it's one name for on-foot/in-vehicle...

Constant	Value	Function OnFoot/InVehicle
LEFTSTICKX	0	Turn/Steer
LEFTSTICKY	1	Move/Lean
RIGHTSTICKX	2	Look/Special CTRL LR
RIGHTSTICKY	3	Look/Special CTRL UD
LEFTSHOULDER1	4	Action/SecFire
LEFTSHOULDER2	5	Scroll Weapon/Look Left
RIGHTSHOULDER1	6	Aim/Handbrake
RIGHTSHOULDER2	7	Scroll Weapon/Look Right
DPADUP	8	Group CTRL Forward/Next Radio Station
DPADDOWN	9	Group CTRL Backward/Prev Radio Station
DPADLEFT	10	No
DPADRIGHT	11	Yes
START	12	Pause (not set in the PC version)
SELECT	13	Change Cam Mode
SQUARE	14	Jump/Brake
TRIANGLE	15	Enter/Exit
CROSS	16	Sprint/Accelerate
CIRCLE	17	Fire Weapon
LEFTSHOCK	18	Crouch/Horn
RIGHTSHOCK	19	Look Behind/Submission

Oh look, ID 12 is actually the START button. Used for the PS2 Pool missions by player 2 to join the game.

BONUS: Pad ID's:

PAD1 - 0
PAD2 - 1

[Wesser]

Here is my documentation.

[Deji]

They also have ON and OFF set to 1/0. Used for 01B4 a lot. Wish they had used enums for car missions and driving styles, though...