Enum Emu 

pub enum Emu {
    Single(Box<Nes>),
    Dual(Box<VsDualSystem>),
}

The top-level emulator: one standard console, or a Vs. DualSystem pair.

v2.0.0 beta.5 — the API reshape scoped to the major (the plan’s Workstream C/D): a NEW rustynes-core consumer would construct via Emu::from_rom and match on the variant; every existing single-console surface lives unchanged on Nes. rustynes-frontend does NOT yet consume this type — it still constructs Nes directly (Nes::from_rom/from_rom_with_sample_rate), so the DualSystem path is core-and-test-harness-only in this release; wiring the desktop/mobile UI onto Emu (dual-console rendering + 4-port input routing) is explicitly deferred, tracked as a beta.5 known gap (see the beta.5 CHANGELOG entry and docs/audit/vs-dualsystem-combined-dumps-2026-07-02.md for the current disposition).

Variants

Single(Box<Nes>)

A standard single-console system (every cart except the four DualSystem boards).

Dual(Box<VsDualSystem>)

A Vs. DualSystem cabinet (two consoles + the cross-wiring).

Implementations

impl Emu

pub fn from_rom(bytes: &[u8]) -> Result<Self, RomError>

Construct the right emulator shape for the ROM: a VsDualSystem when the SHA-keyed vs_db flags the cart as a DualSystem board, else a standard Nes.

Errors

Returns the underlying [RomError] if the bytes don’t parse.

pub fn from_rom_with_sample_rate( bytes: &[u8], sample_rate: u32, ) -> Result<Self, RomError>

Like Self::from_rom, but bakes the frontend’s audio sample rate into the console(s) — the desktop present path uses this so a DualSystem cabinet’s main-console audio resamples to the cpal device rate.

Errors

Returns the underlying [RomError] if the bytes don’t parse.