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The NES you left outside in the rain but let dry and still kind of works
Branch: master
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Nestur is an NES emulator and a work in progress. There are still some minor bugs and the audio is kind of scratchy. I've mostly tested on Donkey Kong, Super Mario Bros., and Zelda so far. There are plenty of full-featured emulators out there; this is primarily an educational project but I do want it to run well. SDL2 is the only dependency, it's NTSC timing, and contains no unsafe code.


 Button  |   Key
|   A    |    D   |
|   B    |    F   |
| Start  |  Enter |
| Select | R-Shift|
|   Up   |   Up   |
|  Down  |  Down  |
|  Left  |  Left  |
|  Right |  Right |

The code aims to follow the explanations from the NES dev wiki where possible, especially in the PPU, and the comments quote from it often. Thanks to everyone who contributes to that wiki/forum, and to Michael Fogleman's NES and Scott Ferguson's Fergulator for getting me unstuck at several points.

Compilation and Use

  1. Install Rust:
  2. Configure SDL2 for your platform:
    • Windows: SDL2.dll is already in the repo so you don't have to do anything.
    • macOS: Install Homebrew and run brew install sdl2
    • Linux: sudo apt-get install libsdl2-dev (or whatever your package manager is)
  3. cd nestur/ && cargo build --release
  4. The nestur executable or nestur.exe will be in nestur/target/release.
  5. Run with $ ./nestur path/to/rom_filename.nes or > nestur.exe path\to\rom_filename.nes.
  6. If the game uses battery-backed RAM (if it can save data when turned off), a save file like rom_filename.sav will be created in the same folder as the ROM when the program is exited. When Nestur is run again, it will look for a file matching the ROM name, with a .sav extension instead of .nes.

To do:

  • More mappers (only mappers 0 (NROM) and 1 (MMC1) implemented so far)

  • DMC audio channel, high- and low-pass filters

  • Save state/load functionality

  • Player 2 controller?

Please also check out Cloaker and Flying Carpet!

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