ov177 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.

(no containers/strings -- pure code)

ov177 tail_data_overlay

(no containers/strings -- pure code)

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 177
File ID 177
RAM load address 0x021fb3c0
RAM size 640 bytes (0x280)
BSS size 0 bytes
On-disk compressed size 600 bytes
Compression flag 0x1 (BLZ-compressed)
Functions 3
External calls 19
Jump tables 1
Data items 14
Code coverage 63% (400 of 640 bytes)

Reading the binary

The overlay ships on the cart at file ID 177 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 + 177 * 0x20, allocates the destination RAM region at 0x021fb3c0, decompresses the body in-place (if compressed), and resolves any external relocations.

To inspect this overlay outside the running game, decompress overlay/overlay_177.bin with ndspy.codeCompression.decompress() (Python ndspy library) and load the resulting plaintext into Ghidra or IDA at base address 0x021fb3c0. The raw Ghidra auto-analysis dump used to populate this page lives at notes/overlay_knowledgebase/raw/ov177.json; the per-overlay descriptive markdown is at notes/overlay_knowledgebase/ov177.md.

Embedded strings

No UTF-16 LE strings are embedded directly in this overlay's binary. Any text it displays at runtime comes from a container file loaded via the content cache.

Container references

This overlay references no container files β€” it is pure code (or reads only from globals shared with the persistent ARM9 binary).

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 3 functions
# Address Size Calls Strings Role hint
1 0x021fb428 356 20 0 code
2 0x021fb5ac 32 1 0 trampoline / small helper
3 0x021fb5d4 12 1 0 trampoline / small helper

Open questions & conflicts

Open questions / unknowns

Conflicts with the prior shallow pass

Source