SRAM Map
Contents
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-$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.
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-$70:09FF, and mirrored at $70:1400-$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 - $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 Low Byte d d d d b k ck cr c c c c q q q q c - chest, big key chest, or big key lock. Any combination of them totalling 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 - $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 - $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 weathervane 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 - $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 - $38B : Item Information
Address | Item | Values | |||
---|---|---|---|---|---|
$340 | Bow | 0 - Nothing | 1 - Bow | 2 - Bow & Arrows | 3 - Bow & Silver Arrows |
$341 | Boomerang | 0 - Nothing | 1 - Blue Boomerang | 2 - Red Boomerang | |
$342 | Hookshot | 0 - Nothing | 1 - Hookshot | ||
$343 | Bombs | 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 | Lantern | 0 - Nothing | 1 - Lantern | ||
$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 | ||
$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 Gloves | 2 - Titan's Mitt |
Boots: $355||0 - Nothing||1 - boots||*Just having the boots isn't enough to dash.
You must have the ability flag corresponding to run set as well. See $379.
Flippers: $356||0 - Nothing||1 - flippers||Having this allows you to swim, but doesn't make
the swim ability text show up by itself||See $379 Unlike the boots, the ability is granted, as long as you have this item.
Moon Pearl: $357||0 - Nothing||1 - moon pearl.
???? $358||Unused? Beginning to think it really is unused||
Not even referenced in the rom by any means that I could see.
Sword: $359.
0-No sword 1-Fighter Sword 2-Master Sword 3-Tempered Sword 4-Golden Sword ***See Side Note 2***
Shield: $35A.
0-No shield 1-Blue Shield 2-Hero's Shield 3-Mirror Shield ***See Side Note 2***
Armor: $35B.
0-Green Jerkin 1-Blue Mail 2-Red Mail ***See Side Note 2***
Bottle: $35C-F
0-No bottle 1-Mushroom (no use) 2-Empty bottle 3-Red Potion 4-Green Potion 5-Blue Potion 6-Fairy 7-Bee 8-Good Bee
Rupees: $360-1 (Goal)
$362-3 (Actual). This number can be set above the 999 limit. It is a word, so you can have lots of rupees. (Up to about 65000) One word is capacity, The other is your current supply.
THE COMPASS, BIG KEY, AND DUNGEON MAP WORD LOCATIONS ARE ALL MAPPED OUT THE SAME WAY, AS YOU WILL OBSERVE.
Note: The unused areas would correspond to dungeon numbers $1C and $1E in the variable $7E040C, but alas there are no dungeons in the game with those values.
If you see "(doesn't exist)" it means this feature was not used in this dungeon in the original, in case you were wondering.
Compass1: $364. bit 0: Unused
bit 1: Unused bit 2: Compass of Ganon's Tower bit 3: Compass of Turtle Rock bit 4: Compass of Gargoyle's domain bit 5: Compass of Tower of Hera bit 6: Compass of Ice Palace bit 7: Compass of Skull Woods.
Compass2: $365 bit 0: Compass of Misery Mire.
bit 1: Compass of Dark Palace bit 2: Compass of Swamp Palace bit 3: Compass of Hyrule Castle 2 (doesn't exist) bit 4: Compass of Desert Palace bit 5: Compass of Eastern Palace bit 6: Compass of Hyrule Castle (doesn't exist) bit 7: Compass of Sewer Passage (doesn't exist)
BigKey1: $366. bit 0: Unused
bit 1: Unused bit 2: Big Key of Ganon's Tower bit 3: Big Key of Turtle Rock bit 4: Big Key of Gargoyle's domain bit 5: Big Key of Tower of Hera bit 6: Big Key of Ice Palace bit 7: Big Key of Skull Woods.
BigKey2: $367. bit 0: Big Key of Misery Mire.
bit 1: Big Key of Dark Palace bit 2: Big Key of Swamp Palace bit 3: Big Key of Hyrule Castle 2 (doesn't exist) bit 4: Big Key of Desert Palace bit 5: Big Key of Eastern Palace bit 6: Big Key of Hyrule Castle bit 7: Big Key of Sewer Passage (doesn't exist)
Dungeon map1: $368. bit 0: Unused
bit 1: Unused bit 2: Map of Ganon's Tower bit 3: Map of Turtle Rock bit 4: Map of Gargoyle's domain bit 5: Map of Tower of Hera bit 6: Map of Ice Palace bit 7: Map of Skull Woods.
Dungeon map2: $369 bit 0: Map of Misery Mire
bit 1: Map of Dark Palace bit 2: Map of Swamp Palace bit 3: Map of Hyrule Castle 2 (doesn't exist) bit 4: Map of Desert Palace bit 5: Map of Eastern Palace bit 6: Map of Hyrule Castle bit 7: Map of Sewer Passage (doesn't exist)
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: Courage
Bit 1: Wisdom Bit 2: Power
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 (value, not bitwise) $3C5: $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.
$3C6: Progress Flags (bitwise)
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. 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. Other wise, 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-$3D8: ????
Player's Name $3D9-$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-$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-$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: $403-4. Counts the number of times your saved or died in the game, before you beat it.
PostGame Death Counter: $405-6. 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-$4FD: ????
Inverse Checksum: $4FE-F. If you add numbers to the file, you need to subtract from this location. See Side Note 3 for more information.
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Appendix:
Side Note 2: Items other than the standard equipment can be equipped. For instance, it's possible to equip the compass as a sword. By some miracle, the items you end up with often work the same way as their appropriate counterparts. Sometimes they are far superior to the normal items, and sometimes they just suck. At least one item makes your armor invincible! Just experiment a little. Beware, the palletes will not be standard.
Side Note 3: A tutorial on inverse checksums. Let's say I add to location $3EE. Now E = 14 in the decimal system. (Note we are looking at the last digit. "E" that is.) Therefore $3EE is even.
If I add a value to a memory location with an even address, I must subtract from the even address of the inverse checksum. Example: Suppose I add $4 to $305. $305 is odd, so I SUBTRACT $4 from the odd checksum byte: $4FF. If I subtracted from $305, I must add to $4FF. This maintains the "balance" of the file and keeps it from being erased.
Now this will work for slight changes in the checksum, but it takes a bit of insight to recognize that the checksum is really a 16-bit number, not just two 8-bit numbers functioning separately.
(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.