A ROM hacking friendly PSX, GBA and NDS assembler with support for overlays and several other neat features. The full MIPS R3000 and ARM7/ARM9 instruction sets are implemented. Unlike other available assemblers, it doesn’t erase existing files.

Note: this is the latest official release. Newer builds of in-progress versions are available at the official buildbot.

Source code is available on GitHub: https://github.com/Kingcom/armips