megaman 2 labels:

$1B: Signal VRAM update - Woodman midboss, others

$23: Held    button status Controller 1
$27: Pressed button status Controller 1

$2A: Current stage you are on
$2B: AI code to run for sprites on $400-41F (00-1F)

$2C: A major control byte for megaman
00 - Teleportation phase
01 - unused (sliding for custom patch)
02 - flashing/invulnerable status
03 - standing still/idle
04 - 1 foot in/stepping
05 - running
06 - in air/jumping
07 - sliding on ground when stopping walk
08 - grabbing onto ladders
09 - Ladders normal
0A - Ladders top of ladder edge
0B - ends a stage

$32-34: TSA/Slope Attribute check mechanics
00: air
01: wall

$36: Timer for how long megaman holds out buster/hand (shooting)

$3B-3C: Y speed to copy to mm for acts

$42: The direction your facing in. 00 = left 40 = right

$47: Signal CHR-RAM update

$4B: Timer for long invisibility lasts for

$51: Signal screen update - Quickman lasers, maybe others

$9A: 1st page weapons bits
$9B: 2nd page weapons bits
$9C-A6: Current life left for weapons

$A7: E tanks, max: 04 in game
$A8: Current lives
$A9: Current selected weapon in-game

$AA: Animation freeze flags - 01: Time Stopper, 03: Teleport, 04: Flashman's Time Stopper on mm, 07: energy
$AC: Heatman weapon charging timer, Mega Buster Charge

$BE: Previous Y position of mm + 2 pixels, for sliding physics
$BF: Sliding timer

$FD-FE: Current Cursor position in weapon menu
    FE: 00: 1st menu page, 01: 2nd menu page
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$356-375: Sprite & BG Palettes

$400-41F: Main sprite animation ID

$420-43F: Sprite Display flags.
Bit 7: Enable/Disable sprite
Bit 6: Right/Left facing
Bit 5:
Bit 4:
Bit 3: 
Bit 2:
Bit 1:
Bit 0: 

$440-45F: Current Screen Number for megaman/sprites, X Screen
$460-47F: X position for megaman/sprites left/right
$480-49F: When <=00 or FF=>, +1/-1 is added to X position's 360-37F

$4A0-4BF: Y position for megaman/sprites up/down
$4C0-4DF: Same as $460-$47F, +1/-1 is added to Y position's 3C0-3DF

$580-58F: Sound Effects/Music ID buffer

$590-59F: Hit detection.
Bit   7: Damage megaman 
Bit   6: Damage Enemey 
Bit   5: Repel hits (if bit 5-6 both 0, then hits go through enemy) 
Bit 4-0: Sprite Size
WARNING! only 90-9F is used for weapons ??

$600-61F: high byte of 16 bit sprite x speeds left/right, fast speed
$620-63F:  low byte of 16 bit sprite x speeds left/right, slow speed

$640-65F: high byte of 16 bit sprite y speeds up/down,    fast speed
$660-67F:  low byte of 16 bit sprite y speeds up/down,    slow speed

$680-69F: Animation Frame Speed Timer
$6A0-6BF: Sprite tile id phases for sprites

$6C0-6DF: HP for enemies/bosses
$6E0-6FF: Copy of 460-47F - X position for mm/sprites, hitbox sizes
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