# Sound and hardware team

Use this team for a device the game drives directly: an FM sound chip, a sound card's digital
channel, a video mode with palette effects, a console's sound CPU. The port reproduces what the
player saw and heard, from the game's own register writes.

```mermaid
flowchart TD
    Ma[re-mapper] -->|device registers, driver functions| O[re-observer]
    O -->|register writes with times, audio or frames| Mt[re-matcher]
    Mt -->|crate or emulator matches the device, or not| T[re-tracer]
    T -->|the game's driver: tempo, timer, write order| P[re-porter]
    P -->|driver in the port, device crate| V[re-verifier]
    V -->|same writes at the same times, audio compared| L[re-lander]
    V -.->|first write that differs| T
    L -->|commit| Done([Device output reproduced])
```

## Steps

| Order | Agent | Brief | Hands on |
|---|---|---|---|
| 1 | `re-mapper` | "Map the <device> registers and the driver functions" | Register labels; the driver's entry points named |
| 2 | `re-observer` | "Capture the <device> writes, with times, for <songs or scenes>" | A list of writes with times in `derived/`; audio or frames |
| 3 | `re-matcher` | "Compare <crate> with the device output" (for example `gameframe-opl2`) | Whether the crate gives the same output from the same writes |
| 4 | `re-tracer` | "Trace the game's <device> driver" | The driver's tempo, its timer, the order of its writes |
| 5 | `re-porter` | "Port the driver and use <crate>" | The game's driver in the port, writing to the device crate |
| 6 | `re-verifier` | "Compare the port's writes and output with the captures" | The same writes at the same times; then audio or frames compared |
| 7 | `re-lander` | "Land the <device> work" | A commit |

## Outcome

- The device's registers and the game's driver, named and documented.
- A port whose driver makes the same writes at the same times as the original.
- Output from a checked device implementation, compared with the captured audio or frames.

## Choices for the main session

- Choose the reference device with the user first, such as an AdLib or a Roland MT-32
  ([Sound](https://tanepiper.github.io/game-frame/hardware/sound.md)), and write it in the project's `AGENTS.md`.
- When no crate covers the device, `re-matcher` checks an existing emulator instead, or the
  team ports the device itself through `re-tracer` and `re-measurer`.