Mega Man 2/RAM map

The following article is a RAM map for Mega Man 2.

General

RAM	Function	Details
$0022	Vertical position of screen scrolling
$0023	Controller 1 Poll
$0025	Controller 1 Mirror
$0027	Controller 1 Poll	Only changes on first frame of state change. Crash Man checks this for jump code.
$002A	Area selected
$0030	Gravity
$004B	Invincibility timer	When above $00, invincibility frames will start and this will count down at a rate of $01 per frame.

Controller values for $0023/$0025/$0027:

Bits	Button
0000 0001	A
0000 0010	B
0000 0100	Select
0000 1000	Start
0001 0000	Up
0010 0000	Down
0100 0000	Left
1000 0000	Right

Sound

RAM	Function	Details
$0066	Sound effects strobe	Write $01 to play the SFX ID in address $0580
$0067	Music strobe	Write $01 to play the Music in address $0000
$0580	Sound effect queue

Player properties

RAM	Function	Details
$06C0	Mega Man's HP
$0460	Mega Man's X location
$04A0	Mega Man's Y location
$0036	Shooting pose timer
$0032	Ground type Mega Man is on (feet)	Value Type $00 Air $01 Ground $02 Ground $05 Right Conveyer $02 Left Conveyer $07 Ice
$0032	Ground type Mega Man is on (center)	See above
$003D	Is Mega Man shooting?
$009A	Unlocked Weapons	Bits Hex Weapon 0000 0001 $01 Atomic Fire 0000 0010 $02 Air Shooter 0000 0100 $04 Leaf Shield 0000 1000 $08 Bubble Lead 0001 0000 $10 Quick Boomerang 0010 0000 $20 Time Stopper 0100 0000 $40 Metal Blade 1000 0000 $80 Crash Bomb
$009B	Unlocked Items	Bits Hex Item 0000 0001 $01 Item 1 (Helicopter Platform) 0000 0010 $02 Item 2 (Jet Sled) 0000 0100 $04 Item 3 (Climbing Platform)
$009C	Atomic Fire Ammo
$009D	Air Shooter Ammo
$009E	Leaf Shield Ammo
$009F	Bubble Lead Ammo
$00A0	Quick Boomerang Ammo
$00A1	Time Stopper Ammo
$00A2	Metal Blade Ammo
$00A3	Crash Bomb Ammo
$00A4	Item 1 Ammo
$00A5	Item 2 Ammo
$00A6	Item 3 Ammo
$00A7	Number of Energy Tanks Remaining	Can go above $04, but will break passwords.
$00A8	Number of Lives remaining	Looks glichy on the pause menu if greater than $64.
$00CB	Difficulty setting	When an enemy takes damage, if this value is $00 (Normal) the damage given will be bitshifted left, doubling it.
$0367-0369	Mega Man's Color Palette

Stage Select

RAM	Function	Details
$002A	Cursor position	$00 is Dr. Wily, $01-$08 goes clockwise starting from Bubble Man.
$0200 - $0203	Heat Man's left eye sprite data	Address Property $0200 Y $0201 Tile $0202 Palette $0203 X
$0200 - $0203	Heat Man's right eye sprite data	Address Property $0204 Y $0205 Tile $0206 Palette $0207 X

Password Screen

RAM	Function	Details
$0420 - $0438	If 01, this grid space contains a dot.	Goes from left to right, top to bottom.
$0680	Number of dots left on Password entering
$0680	Position of cursor on Password entering