Plastic - RetroBIOS¶
Technical notes
NES emulator written in Rust by Amjad Alsharafi. The emulation lives in the plastic_core crate and two binaries drive it: plastic, an egui window, and plastic_tui, a terminal frontend (docs/man/plastic.1). Both take the ROM path as their first argument (plastic_ui/src/main.rs:418-424, plastic_tui/src/main.rs:5-38).
A cartridge boots with nothing supplied. The 2A03, the PPU and every mapper are emulated in software and the console has no boot ROM, so no BIOS or firmware is read. Cartridge::from_file accepts a path only when its extension is nes and its first four bytes are the iNES magic (plastic_core/src/cartridge/mod.rs:184-263, :157-165). get_mapper implements 0, 1, 2, 3, 4, 7, 9, 10, 11, 12 and 66, and any other number returns MapperNotImplemented (:280-296). No Famicom Disk System path exists and therefore no disksys.rom.
The NES to RGB table is a constant compiled into the binary (plastic_core/src/display/color.rs:22-87, selected at :158) and the 32 bytes at 0x3F00 are the PPU palette RAM (plastic_core/src/ppu2c02/palette.rs:6-19), so no palette file is opened. The window icon is embedded at build time (plastic_ui/src/main.rs:430).
The emulator reads back only what it wrote itself. A cartridge whose header
carries the battery bit gets
Gamepad support comes from gilrs, which compiles the SDL controller database into the binary and takes its only override from the SDL_GAMECONTROLLERCONFIG environment variable rather than a file (gilrs src/mapping/mod.rs:477-485).
No BIOS or firmware files required. Generated on 2026-08-23T16:12:06Z