ov074 — overlay detail

DS game only とんがりボウシとおしゃれなまほうつかい The field guide documents the DS game's internals.

containers: map/shop/shop_inte.lzs

ov074 shop

containers: map/shop/shop_inte.lzs

Header

Numeric metadata for this overlay as read from the overlay table at ROM offset 0x8DE00 (per-entry stride 32 bytes). Function counts, data-item counts, and the call-graph fan-out are from a Ghidra 11.3.1 headless auto-analysis pass.

Overlay ID 74
File ID 74
RAM load address 0x021597a0
RAM size 2,784 bytes (0xae0)
BSS size 32 bytes
On-disk compressed size 2,344 bytes
Compression flag 0x1 (BLZ-compressed)
Functions 19
External calls 31
Jump tables 1
Data items 42
Code coverage 61% (1,692 of 2,784 bytes)

Reading the binary

The overlay ships on the cart at file ID 74 under the BLZ code-LZ compression wrapper (the same backward-LZ scheme Nintendo uses for executable ARM9 code). At load time the engine reads the overlay table entry at ROM offset 0x8DE00 + 74 * 0x20, allocates the destination RAM region at 0x021597a0, decompresses the body in-place (if compressed), and resolves any external relocations.

To inspect this overlay outside the running game, decompress overlay/overlay_074.bin with ndspy.codeCompression.decompress() (Python ndspy library) and load the resulting plaintext into Ghidra or IDA at base address 0x021597a0. The raw Ghidra auto-analysis dump used to populate this page lives at notes/overlay_knowledgebase/raw/ov074.json; the per-overlay descriptive markdown is at notes/overlay_knowledgebase/ov074.md.

Embedded strings

1 UTF-16 LE string live inside this overlay's compiled binary. These addresses are absolute (inside the overlay's RAM image after load). The text is stored as little-endian UTF-16 code units, NUL-terminated.

0x02159f5e `れ殩毪氫`

Container references

Distinct container basenames referenced by this overlay. Each is loaded via the content cache by passing the basename string to a lookup that resolves it to a file ID in the ROM's FAT. The path column shows the file's location in the clean extract, where resolved.

Unresolved

These container basenames appeared in the overlay's string table but no file of that name was found in the clean extract. Most are false-positive ASCII matches (function names, register maps, fragments of other strings); a few may be containers that the overlay names but never actually opens. Listed for completeness.

Function list

Functions Ghidra auto-identified inside this overlay's RAM range. Names prefixed FUN_ are auto-generated from the function's entry address; size is in bytes; the "calls" column counts both intra-overlay branches and external ARM9 call targets. The "strings" column counts how many UTF-16 LE strings each function references.

Show all 19 functions
# Address Size Calls Strings Role hint
1 0x02159848 42 2 0 code
2 0x02159880 48 3 0 code
3 0x021598bc 42 2 0 code
4 0x02159978 4 0 0 trampoline / small helper
5 0x0215997c 218 3 0 code
6 0x02159a58 32 2 0 trampoline / small helper
7 0x02159a78 142 6 0 code
8 0x02159b0c 38 1 0 trampoline / small helper
9 0x02159c00 406 19 0 code
10 0x02159db4 14 0 0 trampoline / small helper
11 0x02159dc4 214 7 1 refs: map/shop/shop_inte.lzs
12 0x02159eb4 216 5 0 code
13 0x02159f90 56 2 0 code
14 0x02159fcc 36 2 0 trampoline / small helper
15 0x02159ff4 36 2 0 trampoline / small helper
16 0x0215a01c 36 2 0 trampoline / small helper
17 0x0215a044 36 2 0 trampoline / small helper
18 0x0215a108 44 3 0 code
19 0x0215a134 32 2 0 trampoline / small helper

Open questions & conflicts

Open questions / unknowns

Conflicts with the prior shallow pass

Source