NES Emulator

🇪🇸 ES | 🇺🇸 EN

Built from scratch. Learn how in the book.

Load a .nes ROM to play.

Don't have a ROM? Download .nes files from Retrostic, RomsFun or Emu-Land.

Controls
D-Pad	Arrow Keys
A	Z
B	X
Start	Enter
Select	Shift

Building Your First Emulator

This emulator is the project you’ll build in the book.

We write a NES emulator from scratch, no libraries, no third-party code. We start with a processor that does nothing and end up running Super Mario Bros.

Code first, theory after. Every design decision explained in an informal, practical tone. No emulation or hardware experience needed.

151 CPU instructions, registers, flags, interrupts
PPU graphics pixel by pixel with 2 KB of RAM
Real-time audio with the APU
Parse real cartridges (iNES format)
Run Mario, Zelda, Contra and dozens of classics

Available in Spanish and English.

Get the Book Read the Blog

Download a Free Sample