SRAM Map

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Overview

All offsets presented here are relative to the start of each save slot. There are $500 bytes for each slot. Note that each slot is mirrored, at a later point in SRAM.

  • Slot 1: $000; Mirror: $F00
  • Slot 2: $500; Mirror: $1400
  • Slot 3: $A00; Mirror: $1900

Only edits to the main copy will be recognized by the game unless the main copy fails its checksum. Each copy has its own checksum.

Addresses $1E00 to $1FFE in SRAM are not used. No not assume that the free addresses are initialized to any specific or sensible value. The values from these addresses should be treated as undefined until initialized. Address $1FFF is used by the game to store temporary data.

$1FFE is used as the offset to know where the memory will be stored in the SRAM (02 is the first file, 04 the second and 06 the third)

These offsets directly correspond to $7E:F--- for a particular save file is being played. When the game is finished it writes the information into bank $70 in the corresponding slot + offsets presented here. (e.g. For the second save file, the information will be saved to $70:0500 to $70:09FF, and mirrored at $70:1400 to $70:18FF.)

Warning

The SRAM save loading routing relies upon an inverse checksum. Additions to any byte in the .srm file, must be subtracted from that save game's checksum to maintain integrity. Failure to observe this precaution will cause the game to attempt to load the mirror copy. Should the mirror copy also fail the checksum verification, the save slot will be cleared.

SRAM Map

$000 to $24F = Data for Rooms

Room Information: There are $128 (296) rooms in in the ROM. Each room has one word of information devoted to it.

High Byte d d d d b k ck cr

Low Byte c c c c q q q q


  • c - chest, big key chest, or big key lock. Any combination of them totaling to 6 is valid.
  • q - quadrants visited:
  • k - key or item (such as a 300 rupee gift)
  • d - door opened (either unlocked, bombed or other means)
  • r - special rupee tiles, whether they've been obtained or not.
  • b - boss battle won

qqqq corresponds to 4321, so if quadrants 4 and 1 have been "seen" by Link, then qqqq will look like 1001. The quadrants are laid out like so in each room:

4 3
2 1

$250 to $27F = Unused

This area is believed to have been left to store additional room information that was not included in the final game. This would bring the grand total to $140 (320) possible rooms.

$280 to $2FF = Overworld Event Information

(one byte per area)

?ho???s?

  • o - If set, the area will draw its designated overlay when you enter it. e.g. If you're triggered misery mire then the entrance shows up there the next time you enter that area. You can view overlays in the latest release of Hyrule Magic (v0.963). Other overlays include stairs leading underground, and the removal of the weather vane after it has exploded.
  • s - If set, the area will draw its secondary overlay when you enter it.
  • h - If set, heart piece has been collected in this area already. Also used for a handful of other sprites.
  • ? - unknown and probably unused.

$300 to $33F = Unused

This area is believed to have been left to store additional overworld data that was not included in the final game. This would allow for $C0 (192) overworld areas in total. Note areas $80 and $82 are used but don't save data the way the other areas do. (i.e. not here)

$340 to $38B = Items & Equipment

Address Item Values Notes
$340 Bow 0 - Nothing 1 - Bow 2 - Bow & Arrows 3 - Silver Arrow Bow 4 - Bow & Silver Arrows Confirmed correct 4/19/16.
$341 Boomerang 0 - Nothing 1 - Blue Boomerang 2 - Red Boomerang
$342 Hookshot 0 - Nothing 1 - Hookshot
$343 How many bombs you have   Can exceed 0x32 (50), up to 0xFF (255).
$344 Magic Powder 0 - Nothing 1 - Mushroom 2 - Magic Powder
$345 Fire Rod 0 - Nothing 1 - Fire Rod
$346 Ice Rod 0 - Nothing 1 - Ice Rod
$347 Bombos Medallion 0 - Nothing 1 - Bombos Medallion
$348 Ether Medallion 0 - Nothing 1 - Ether Medallion
$349 Quake Medallion 0 - Nothing 1 - Quake Medallion
$34A Lamp 0 - Nothing 1 - Lamp
$34B Magic Hammer 0 - Nothing 1 - Magic Hammer
$34C Flute 0 - Nothing 1 - Shovel 2 - Flute 3 - Flute & Bird
$34D Bug Catching Net 0 - Nothing 1 - Bug Catching Net
$34E Book of Mudora 0 - Nothing 1 - Book of Mudora
$34F Bottles 0 - Nothing 1 - Bottle 1 ($7EF35C) 2 - Bottle 2 ($7EF35D) 3 - Bottle 3 ($7EF35E) 4 - Bottle 4 ($7EF35F)
$350 Cane of Somaria 0 - Nothing 1 - Cane of Somaria
$351 Cane of Byrna 0 - Nothing 1 - Cane of Byrna
$352 Magic Cape 0 - Nothing 1 - Magic Cape
$353 Magic Mirror 0 - Nothing 1 - Magic Scroll 2 - Magic Mirror
$354 Gloves 0 - Nothing 1 - Power Glove 2 - Titan's Mitt
$355 Pegasus Boots 0 - Nothing 1 - Pegasus Boots   Just having the boots isn't enough to dash. The player must have the "Run" ability flag set as well. See $379.
$356 Zora's Flippers 0 - Nothing 1 - Zora's Flippers   Having this allows you to swim, but doesn't make the swim ability text show up by itself. See $379. Unlike with the Pegasus Boots, the ability to swim is granted as long as the player has this item.
$357 Moon Pearl 0 - Nothing 1 - Moon Pearl
$358 Unused (See note)   Can be clobbered by fairy fountains.
$359 Sword 0 - No sword 1 - Fighter's Sword 2 - Master Sword 3 - Tempered Sword 4 - Golden Sword ***See Side Note 2***
$35A Shield 0 - No shield 1 - Blue Shield 2 - Hero's Shield 3 - Mirror Shield   ***See Side Note 2***
$35B Armor 0 - Green Jerkin 1 - Blue Mail 2 - Red Mail   ***See Side Note 2***
$35C to $35F Bottle Contents 0 - No bottle 1 - Mushroom 2 - Empty bottle 3 - Red Potion 4 - Green Potion
5 - Blue Potion 6 - Fairy 7 - Bee 8 - Good Bee
$360 to $361 Wallet Capacity   This number can be set above the 999 limit.
$362 to $363 Rupee Count

THE COMPASS, BIG KEY, AND DUNGEON MAP WORD LOCATIONS ARE ALL MAPPED OUT THE SAME WAY, AS YOU WILL OBSERVE.


Item Address Bit 0 Bit 1 Bit 2 Bit 3 Bit 4 Bit 5 Bit 6 Bit 7
Compass1 $364 Unused Unused Ganon's Tower Turtle Rock Gargoyle's domain Tower of Hera Ice Palace Skull Woods.
BigKey1 $366
Dungeon map1 $368
Compass2 $365 Misery Mire. Dark Palace Swamp Palace Hyrule Castle 2 (doesn't exist) Desert Palace Eastern Palace Hyrule Castle (doesn't exist) Sewer Passage (doesn't exist)
BigKey2 $367
Dungeon map2 $369

Wishing Pond Rupee $36A

  • Number of rupees in the pond Count

Heart pieces collected:

  • $36B. Number of heart pieces (out of four) you have earned

Health: $36C

  • Goal (capacity) Health. Each increment of $08 is worth one heart.
  • $04 is a half heart. The max is generally $A0. The game is coded to not accept health values beyond this.
  • $36D. Actual Health. Same as above, but this reflects your current health status rather than potential.

Magic Power: $36E

  • Magic power ranges from $0 to $80 (128). Each small bottle refills $10. Setting Magic above $80 causes the magic meter to glitch and you can't use special items.

Keys: $36F

  • Number of Keys you have in the dungeon you are currently in. You can earn keys on the overworld but they don't do anything. If you're in a non-keyed dungeon it will generally read $FF.

Bomb Upgrades: $370

  • Number of upgrades your bomb capacity has received. Behavior varies after a while. Will probably need recoding to be consistent.

Arrow Upgrades: $371

  • Number of upgrades your arrow capacity has received. Same as above, more or less.

Hearts filler: $372

  • Write to this location to fill in a set number of hearts. Make sure to write in a multiple of $08 Otherwise, you will end up filling the whole life meter.

Magic filler: $373

  • Write to this location how much magic power you want filled up. The maximum effective value is $80.

Pendants: $374

  • Bit 0: Red/Wisdom/Hera
  • Bit 1: Blue/Power/Desert
  • Bit 2: Green/Courage/Eastern Palace

Bomb filler: $375

  • Write to this location to add X bombs to your arsenal. It will not exceed your maximum, as defined with $370.

Arrow filler: $376

  • Write to this location to add X arrows to your arsenal. It will not exceed your maximum, as defined with $371.

Arrows: $377

  • Can exceed 70.

????: $378

  •  ????

Ability Flags: $379

  • Bit 0:
  • Bit 1: Swim
  • Bit 2: Run / Dash
  • Bit 3: Pull
  • Bit 4: ----
  • Bit 5: Talk
  • Bit 6: Read
  • Bit 7: ----

Crystals: $37A

  • Bit 0: Misery Mire
  • Bit 1: Dark Palace
  • Bit 2: Ice Palace
  • Bit 3: Turtle Rock
  • Bit 4: Swamp Palace
  • Bit 5: Gargoyle's Domain
  • Bit 6: Skull Woods

Magic usage: $$37B

  • $0: normal consumption
  • $1: 1/2 consumption
  • $2: 1/4 consumption

Keys earned per dungeon:

  • $37C = Sewer Passage
  • $37D = Hyrule Castle
  • $37E = Eastern Palace
  • $37F = Desert Palace
  • $380 = Hyrule Castle 2
  • $381 = Swamp Palace
  • $382 = Dark Palace
  • $383 = Misery Mire
  • $384 = Skull Woods
  • $385 = Ice Palace
  • $386 = Tower of Hera
  • $387 = Gargoyle's Domain
  • $388 = Turtle Rock
  • $389 = Ganon's Tower
  • $38A = ??? possibly unused. (Were they planning two extra dungeons perhaps?)
  • $38B = ??? possibly unused.

Game Event Information

Progress Indicator $3C5 (value, not bitwise):

  • $0 = Unset, Will put Link in his bed state at the beginning of the game. (Also can't use sword or shield)
  • $1 = You have a sword and start in the castle on start up.
  • $2 = Indicates you have completed the first Hyrule Castle dungeon.
  • $3 = Indicates you have beaten Agahnim and are now searching for crystals.
  • $4 and above = meaningless. Though, you could write code using them to expand the event system perhaps.

Progress Flags (bitwise)$3C6:

  • 0 = Set after your Uncle gives you his gear in the secret passage. Prevents him from showing up there again.
  • 1 = Indicates that you've touched the dying priest in Sanctuary.
  • 2 = Set after you bring Zelda to sanctuary?
  • 3 = Unused? (98% certainty)
  • 4 = Set after Link's Uncle leaves your house. It's used to prevent him from respawning there.
  • 5 = Set after you obtain the Book of Mudora (this is a guess)
  • 6 = Seems to be a persistent flag that toggles between two possible statements that a fortune teller can give you during your "reading". In other words, don't expect this to stay in one state if you're using fortune tellers. Has no other known purpose.
  • 7 = Unused? (98% certainty)

Map Icons Indicator 2 (value, not bitwise) $3C7:

  • 0x00 = ????
  • 0x01 = ????
  • 0x02 = ????
  • 0x03 = The Three Pendants
  • 0x04 = Master Sword in Lost Woods
  • 0x05 = Agahnim (skull icon at Hyrule Castle)
  • 0x06 = Just crystal 1 shown (Sahasrala's idea)
  • 0x07 = All crystals shown
  • 0x08 = Agahnim (skull icon at Ganon's Tower)

All values beyond 8 are invalid, it seems.

Starting Entrance to use: $3C8: Abbreviations:

  • LH = Link's House;
  • SA = Sanctuary;
  • MC = Mountain Cave;
  • PP = Pyramid of Power in DW;
  • 0 = Start the game in Link's house always.
  • 1 = SA.
  • 2 = Start in Zelda's Cell (entrance index sanc?).
  • 3 = Secret passage under HC garden (near dying uncle).
  • 5 = LH or SA or MC.


Progress Indicator 3 (bitwise) $3C9:

  • 0 = If set, means the bum gave you his bottle already.
  • 1 = If set, means that the salesman in the village sold you a bottle already
  • 2 =
  • 3 = Flute Boy (DW) has been arborated
  • 4 = Thief's Chest has been opened by the middle aged guy
  • 5 = After you save the Smithy's partner, this bit gets set.
  • 6
  • 7 = Means Smithies have your sword. Once they give it back it's no longer set. (so nonpermanent)

Lightworld / Darkworld $3CA:

  • 0
  • 1
  • 2
  • 3
  • 4
  • 5
  • 6 = If set, we're in dark world. Otherwise, in light world.
  • 7

Unused? $3CB:

  •  ?????

$3CC[0x01] - (Tagalong)

  • Tagalong Indicator (who is following you, if anyone?) (value based)

Note: Don't use a value of 0x0F or larger here, as it will likely crash the game.

  • 0x00 = Tagalong disabled
  • 0x01 = Princess Zelda
  • 0x02 =  ???
  • 0x03 =  ???
  • 0x04 = Old Man?
  • 0x05 = Zelda (invisible) bitching at you about coming to rescue her.
  • 0x06 = Blind masquerading as a Maiden
  • 0x07 = Missing Dwarf (smithyfrog as I call him) in DW
  • 0x08 = Missing Dwarf in LW
  • 0x09 = Middle Aged Guy w/ Sign
  • 0x0A = Kiki the monkey
  • 0x0B =  ???
  • 0x0C = Thief's chest
  • 0x0D = Super Bomb
  • 0x0E = Activated in reaction to acquiring the Master Sword. Used to trigger a telepathic message from Zelda indicating that Agahnim's goons have come for her at Sanctuary.

$03CD[0x02] -

  • Cached Y coordinate of Tagalong after it has been lost by the player. Applies to the old man and to the super bomb, at the very least. This is intended to be used not as a save game variable, but rather as a means of picking the Tagalong back up by getting in contact with it.

$03CF[0x02] -

  • Cached X coordinate of Tagalong after it has been lost by the player. Applies to the old man and to the super bomb, at the very least. This is intended to be used not as a save game variable, but rather as a means of picking the Tagalong back up by getting in contact with it.

$3D1:

  •  ????

$3D2:

$3D3:

  • Set to 0 normally. Set to $80 if a Super Bomb is going off.

$3D4 to $3D8:

  •  ????

Player's Name $3D9 to $3E4:

  • See appendix for listing of character codes. Note each of the six letters is represented by a 16-bit number.

Validity (Checksum) of the File: $3E5 to $3E6:

  • There is a subroutine in the ROM that checks to make sure this value is 0x55AA. (Note the reverse byte order in the actual SRAM.) If you alter this your file is automatically tagged for deletion at startup. The game is designed to delete it, it's not a Super NES feature or anything. In short, Don't mess with it. Unused game slots have the value 0x0000 here, and you will too if you mess with it - resulting in your save file(s) being wiped out.

$3E7 to $402 (?) = Deaths totals for each dungeon. Each number is 16 bit. Thanks to Euclid for helping verify this!

  • $3E7 = Sewers
  • $3E9 = Hyrule Castle
  • $3EB = Eastern Palace
  • $3ED = Desert Palace
  • $3EF = Hyrule Castle 2
  • $3F1 = Swamp Palace
  • $3F3 = Dark Palace
  • $3F5 = Misery Mire
  • $3F7 = Skull Woods
  • $3F9 = Ice Palace
  • $3FB = Tower of Hera
  • $3FD = Gargoyle's Domain
  • $3FF = Turtle Rock
  • $401 = Ganon's Tower

Life/Save Counter: $403 to $404

  • Counts the number of times your saved or died in the game, before you beat it.

PostGame Death Counter: $405 to $406

  • When you start the game this is written to with the value -1 (0xFFFF). On the game select screen, it will only display a number if this is not 0xFFFF. The max displayable number is 999.

When you beat the game, the number of times you died gets recorded here.

Presumed to be unused: $407 to $4FD

  •  ????

Inverse Checksum: $4FE to $4FF

  • If you add numbers to the file, you need to subtract from this location. See Side Note 3 for more information.
===================================================================================

Appendix:



(edit later)


Character Codes:

Alpha-numeric

00 = A
01 = B
02 = C
03 = D
04 = E
05 = F
06 = G
07 = H
08 = I^
09 = J
0A = K
0B = L
0C = M
0D = N
OE = O
OF = P
10 = ??
20 = Q
21 = R
22 = S
23 = T
24 = U
25 = V
26 = W
27 = X
28 = Y
29 = Z
2A = a
2B = b
2C = c
2D = d
2E = e
2F = f
40 = g
41 = h
42 = k
43 = j
44 = i
45 = l
46 = m
47 = n
48 = o
49 = p
4A = q
4B = r
4C = s
4D = t
4E = u
4F = v
60 = w
61 = x
62 = y
63 = z
64 = 0
65 = 1
66 = 2
67 = 3
68 = 4
69 = 5
6A = 6
6B = 7
6C = 8
6D = 9
6E = "?"
6F = "!"
80 = " = "
81 = "."
82 = ","

85 = "("
86 = ")"

Special characters (not normally accessible. This is by far an incomplete listing)

$A0 small right Arrow
$A1 "'" (apostrophe)
$A2 HPiece Again
$A3 "empty right hand heart cont."
$A4 see
$A7
$A5 Same As
$A7
$A6 "Quarter Heart piece, top right corner."
$A7 "Heart piece,left half"
$A8 "Heart piece, right half"
$A9 blank
$AA "left Arrow"


SNES Button Alphabet:

$AB A
$AC B
$AD X
$AE Y
$AF I
$B1 blank^

^This code is not the canon encoding of this character. ex. AF is the proper "I". 08 is not.


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