Emulators

FCEUX

NES emulation and development

FCEUX combined accurate NES emulation with powerful debugging and development tools, making it essential for both players and homebrew developers.

nintendo-entertainment-system emulatornesdevelopment 2008

Overview

FCEUX emerged from the merger of FCE Ultra and FCEU-mm, combining accurate NES emulation with extensive development and debugging features. The emulator supports tool-assisted speedrun creation, ROM hacking, and homebrew development alongside standard gameplay. Its combination of accuracy and tooling made it the go-to choice for NES-related work.

Fast facts

  • Origin: merge of FCE Ultra and FCEU-mm (2008).
  • Platform: Windows, Linux, macOS.
  • Features: debugging, TAS tools, Lua scripting.
  • Accuracy: good compatibility, not cycle-perfect.
  • Purpose: playing, debugging, ROM hacking, TAS creation.

Development features

Tools for creators:

  • Debugger: breakpoints, memory viewing.
  • Trace logger: instruction-by-instruction output.
  • Hex editor: direct memory/ROM modification.
  • Code/data logger: identify code vs data.
  • Name table viewer: see tile arrangements.

TAS support

Tool-assisted speedrun features:

  • Frame advance: step through one frame at a time.
  • Rerecording: save states with input history.
  • Lua scripting: automated testing and display.
  • Input display: show controller inputs.

See also