ov156 β€” overlay detail

DS game only γ¨γ‚“γŒγ‚Šγƒœγ‚¦γ‚·γ¨γŠγ—γ‚ƒγ‚Œγͺまほう぀かい The field guide documents the DS game's internals.

containers: map/rep/repevo.ofs, npc/NpcParamNpc.ofs

ov156 other

containers: map/rep/repevo.ofs, npc/NpcParamNpc.ofs

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 156
File ID 156
RAM load address 0x021b6080
RAM size 46,400 bytes (0xb540)
BSS size 96 bytes
On-disk compressed size 39,272 bytes
Compression flag 0x1 (BLZ-compressed)
Functions 29
External calls 105
Jump tables 1
Data items 118
Code coverage 15% (6,926 of 46,400 bytes)

Reading the binary

The overlay ships on the cart at file ID 156 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 + 156 * 0x20, allocates the destination RAM region at 0x021b6080, decompresses the body in-place (if compressed), and resolves any external relocations.

To inspect this overlay outside the running game, decompress overlay/overlay_156.bin with ndspy.codeCompression.decompress() (Python ndspy library) and load the resulting plaintext into Ghidra or IDA at base address 0x021b6080. The raw Ghidra auto-analysis dump used to populate this page lives at notes/overlay_knowledgebase/raw/ov156.json; the per-overlay descriptive markdown is at notes/overlay_knowledgebase/ov156.md.

Embedded strings

6 UTF-16 LE strings 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.

0x021b6aa8 `榀ご瀁頇`
0x021b6aec `榀ご瀁両`
0x021bbd2c `頏逐ン逐`
0x021bd062 `逅る逅頂送`
0x021bec4b `へ朘緢淽`
0x021c0ba2 `ι€Šι ‹γ‚’ι€‹`

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 29 functions
# Address Size Calls Strings Role hint
1 0x021b6088 324 17 0 code
2 0x021b81d8 712 33 0 high-fan-out (likely dispatcher / setup)
3 0x021b84b0 6 0 0 trampoline / small helper
4 0x021b84b8 356 17 0 code
5 0x021b8624 306 14 0 code
6 0x021ba17c 496 16 0 code
7 0x021ba374 396 13 0 code
8 0x021ba500 652 12 0 code
9 0x021ba78c 8 0 0 trampoline / small helper
10 0x021bab68 242 9 0 code
11 0x021bad24 16 0 0 trampoline / small helper
12 0x021bad38 12 1 0 trampoline / small helper
13 0x021bad48 12 0 0 trampoline / small helper
14 0x021bb518 246 6 0 code
15 0x021bc06c 90 3 0 code
16 0x021bc0c8 36 3 0 trampoline / small helper
17 0x021bcde0 462 11 0 code
18 0x021bd114 686 42 0 high-fan-out (likely dispatcher / setup)
19 0x021be558 116 3 0 code
20 0x021be5e0 126 12 0 code
21 0x021be664 46 3 0 code
22 0x021be698 380 19 0 code
23 0x021bedfc 372 37 0 high-fan-out (likely dispatcher / setup)
24 0x021c0ca0 366 31 0 high-fan-out (likely dispatcher / setup)
25 0x021c0e58 2 0 0 trampoline / small helper
26 0x021c0e5c 78 5 0 code
27 0x021c0eb0 20 0 0 trampoline / small helper
28 0x021c0ec8 148 11 0 code
29 0x021c0f60 214 17 0 code

Open questions & conflicts

Open questions / unknowns

Conflicts with the prior shallow pass

Source