I built a RISC-V emulator that runs DOOM

In plain words

This is a RISC-V emulator that supports the RV32IM instruction set and runs the classic game DOOM. Built by an individual developer, it implements ELF loading and a minimal syscall interface using newlib to execute C programs. The emulator can render DOOM to a fixed memory area and demonstrates full compatibility with complex software beyond simple assembly programs.

written from the facts on this page · September 2026

From the sources

A tiny RISC-V emulator that runs DOOM. Contribute to lalitshankarch/rvcore development by creating an account on GitHub.

rvcore is a RISC-V emulator that serves as a minimal environment capable of running DOOM. It implements the RV32IM ISA except for the FENCE and EBREAK instructions, which are currently stubbed. mkdir build cmake -B build -DCMAKE_BUILD_TYPE=Release cd build cmake --build . Build instructions for doomgeneric Clone https://github.com/lalitshankarch/doomgeneric riscv64-unknown-elf-gcc or the riscv64-gnu-toolchain configured with ./configure --with-multilib-generator="rv32im-ilp32--" must be installed Navigate to doomgeneric and run make Running other programs Navigate to the examples directory to see how to run simple C programs on rvcore . Only a few essential newlib stubs are implemented. To…from github.com

In the maker’s words, at launch

Demo: https://www.youtube.com/watch?v=f5uygzEmdLw Hi HN, I built a RISC-V emulator that implements the RV32IM instruction set and a minimal syscall interface to run DOOM. A few weeks ago, I got my first output with a simple hello world assembly program. Since then I have been working tirelessly to get…

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