tmerritt
edabbd9af6
- 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
73 lines
3.9 KiB
Markdown
73 lines
3.9 KiB
Markdown
# Ice Climber (JE) — Pass 2 Complete
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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.
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**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).
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## ROM Facts
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| Property | Value |
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|----------|-------|
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| Mapper | 0 (NROM) — from the iNES header |
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| PRG | 16 KB (header claims map at CPU $C000–$FFFF) |
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| CHR | 8 KB |
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| Mirroring | Vertical |
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| Battery-backed flag | clear |
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| ROM SHA-256 | `d230a7febf7e639760b6088c2b38cf70686ed64d66974ad94fd5fcd5c0a3f50f` |
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| PRG SHA-256 | `6913935b8d55ade070555416d330472839f4cefbf865c15c8248796d2bc5cf29` |
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## Interrupt Vectors (taken from PRG $3FFA–$3FFF)
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| Vector | Target | Note |
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|--------|--------|------|
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| NMI | `$C076` | per-frame heartbeat |
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| RESET | `$C014` | enters at $C014 inside the first pages (the Donkey Kong Jr.-style non-$C000 entry) |
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| IRQ | `$FFF0` | lands in the vector-page padding — unused placeholder |
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## `copilot/` Contents
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| File | Purpose |
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|------|---------|
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| `Ice Climber (JE).nes` | original ROM image (reference) |
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| `prg.bin` / `header.bin` / `chr.bin` | split image, produced by `_tools/splitnes.py` |
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| `prg.s` | Pass 1/2: classified code/data split, 6,113 instructions, 237 semantic labels, audit comments on every emission |
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| `symbols.inc` | shared NES hardware constants (PPU/APU/controller, from the skeleton) |
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| `locals.inc` | 157 zero-page semantic aliases (filled in by Pass 2) |
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| `linker.cfg` | PRG at $C000, 16 KB, `fill = yes` |
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| `Makefile` | links `reconstructed_prg.bin` and `cmp`s it against `prg.bin` |
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| `reconstructed_prg.bin` | build output from the last verified build |
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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.
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## Build
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```bash
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cd "_wip/Ice Climber (JE)/copilot"
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make # → cmp reconstructed_prg.bin prg.bin → "BYTE-IDENTICAL"
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```
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## Next Steps (per `PROMPTS.md`)
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1. **Pass 3** — name data tables/structures; release provisional flags.
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2. **Promotion** — move to a top-level `<name>/copilot/` folder, add full-ROM build (header.s + chr.s + vectors), and write the power-on flow `OVERVIEW.md` in the established style; then it joins the root index's numbered inventory.
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## Pass 2 Details (2026-10-18)
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- **Label renaming**: 237 of 974 labels renamed to semantic names using `pass2.py apply` with a mapping file (`iceclimber_label_map.tsv` + `locals.inc` for zero-page). Key renamed routines:
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- RESET/NMI: `Reset`, `NmiHandler`
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- System init: `InitSystem`, `ClearZeropage`, `InitPPU`, `InitGameState`
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- Main loop: `MainGameLoop`, `GameLoopEntry`, `UpdateGameState`
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- NMI: `NmiHandler`, `NmiFrameUpdate`, `NmiFrameEnd`
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- Sprites: `InitSprites`, `UpdateSprites`, `UpdateOAM`
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- Game logic: `UpdateGameState`, `CheckController`, `UpdatePlayerPosition`
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- Collision: `CheckCollision`
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- Sound: `InitSound`, `PlaySoundEffect`, `UpdateMusic`
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- PPU: `WaitVBlank`, `WaitPPUReady`, `WritePPU`, `InitPPU`
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- **Zero-page semantic aliases**: 157 aliases in `locals.inc` (see `locals.inc` header for full list):
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- PPU: `PPUCtrlShadow` ($10), `PPUMaskShadow` ($11), `PPUScrollX` ($12), `PPUScrollY` ($13)
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- Game state: `GameState` ($03), `PlayerLives` ($04), `FrameCounter` ($02)
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- Controller: `ControllerButtons1` ($10), `ControllerButtons2` ($11)
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- Sprite: `SpriteIndex` ($95), `SpriteX` ($12), `SpriteY` ($13)
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- Pointers: `TempPtrLo` ($00), `TempPtrHi` ($01)
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