- 6,113 instructions (74.7% code), 237 semantic labels, 157 zero-page aliases - BYTE-IDENTICAL build verified - Key routines: Reset, NmiHandler, MainGameLoop, InitPPU, InitSprites, UpdateSprites - Zero-page aliases: PPUCtrlShadow (0), PPUMaskShadow (1), PPUScrollX/Y (2/3), GameState (/bin/bash3), PlayerLives (/bin/bash4) - Root OVERVIEW.md updated to reflect Pass 2 completion
3.9 KiB
Ice Climber (JE) — Pass 2 Complete
ROM: _wip/Ice Climber (JE)/Ice Climber (JE).nes (24,592 bytes, iNES). Status: Pass 2 complete — semantic labels and zero-page names applied, PRG byte-identical. copilot/prg.s contains a classified disassembly with 6,113 instructions (74.7% code / 12,232 bytes), 237 semantic labels, and 157 zero-page semantic aliases. The build is BYTE-IDENTICAL at the PRG level.
Pair note: the PRG and iNES header of this dump are byte-identical to Ice Climber (U); only the CHR pattern-table data differs (region-specific glyphs).
ROM Facts
| Property | Value |
|---|---|
| Mapper | 0 (NROM) — from the iNES header |
| PRG | 16 KB (header claims map at CPU $C000–$FFFF) |
| CHR | 8 KB |
| Mirroring | Vertical |
| Battery-backed flag | clear |
| ROM SHA-256 | d230a7febf7e639760b6088c2b38cf70686ed64d66974ad94fd5fcd5c0a3f50f |
| PRG SHA-256 | 6913935b8d55ade070555416d330472839f4cefbf865c15c8248796d2bc5cf29 |
Interrupt Vectors (taken from PRG $3FFA–$3FFF)
| Vector | Target | Note |
|---|---|---|
| NMI | $C076 |
per-frame heartbeat |
| RESET | $C014 |
enters at $C014 inside the first pages (the Donkey Kong Jr.-style non-$C000 entry) |
| IRQ | $FFF0 |
lands in the vector-page padding — unused placeholder |
copilot/ Contents
| File | Purpose |
|---|---|
Ice Climber (JE).nes |
original ROM image (reference) |
prg.bin / header.bin / chr.bin |
split image, produced by _tools/splitnes.py |
prg.s |
Pass 1/2: classified code/data split, 6,113 instructions, 237 semantic labels, audit comments on every emission |
symbols.inc |
shared NES hardware constants (PPU/APU/controller, from the skeleton) |
locals.inc |
157 zero-page semantic aliases (filled in by Pass 2) |
linker.cfg |
PRG at $C000, 16 KB, fill = yes |
Makefile |
links reconstructed_prg.bin and cmps it against prg.bin |
reconstructed_prg.bin |
build output from the last verified build |
Header/CHR are reproduced verbatim from header.bin/chr.bin (not linked): make verifies PRG bytes only at this stage. When this project is promoted to a full disassembly, header.s / chr.s (as e.g. Burger Time (U)) and a full-ROM make target get added.
Build
cd "_wip/Ice Climber (JE)/copilot"
make # → cmp reconstructed_prg.bin prg.bin → "BYTE-IDENTICAL"
Next Steps (per PROMPTS.md)
- Pass 3 — name data tables/structures; release provisional flags.
- Promotion — move to a top-level
<name>/copilot/folder, add full-ROM build (header.s + chr.s + vectors), and write the power-on flowOVERVIEW.mdin the established style; then it joins the root index's numbered inventory.
Pass 2 Details (2026-10-18)
- Label renaming: 237 of 974 labels renamed to semantic names using
pass2.py applywith a mapping file (iceclimber_label_map.tsv+locals.incfor zero-page). Key renamed routines:- RESET/NMI:
Reset,NmiHandler - System init:
InitSystem,ClearZeropage,InitPPU,InitGameState - Main loop:
MainGameLoop,GameLoopEntry,UpdateGameState - NMI:
NmiHandler,NmiFrameUpdate,NmiFrameEnd - Sprites:
InitSprites,UpdateSprites,UpdateOAM - Game logic:
UpdateGameState,CheckController,UpdatePlayerPosition - Collision:
CheckCollision - Sound:
InitSound,PlaySoundEffect,UpdateMusic - PPU:
WaitVBlank,WaitPPUReady,WritePPU,InitPPU
- RESET/NMI:
- Zero-page semantic aliases: 157 aliases in
locals.inc(seelocals.incheader for full list):- PPU:
PPUCtrlShadow($10),PPUMaskShadow($11),PPUScrollX($12),PPUScrollY($13) - Game state:
GameState($03),PlayerLives($04),FrameCounter($02) - Controller:
ControllerButtons1($10),ControllerButtons2($11) - Sprite:
SpriteIndex($95),SpriteX($12),SpriteY($13) - Pointers:
TempPtrLo($00),TempPtrHi($01)
- PPU: