Bass

Bass is a macro assembler for 6502 cross-development written by Aleksi Eeben in 2025. It is designed to be minimalistic, clutter-free, precise, beautiful, and fun — with minimal mental overhead from remembering directive structures or unnecessary formalities. Just write code and sip some coffee all night. If you’ve used DASM or ASM-One, you’ll feel instantly at home.

Bass is written in Lua, with precompiled binaries available for macOS, Windows, Linux PCs, and the Raspberry Pi 5. (Pi 3 or 4 with 64-bit OS installed should work too.)

Lua bytecode version is also provided, built on Lua 5.4.8.

Version 1.01 (25 Sep 2025) adds one directive, a few error checks, and corrects a blocked variable name.

See the Bass Manual for detailed information.

Download the latest version of Bass via Dropbox or Google Drive.

Note: You may not use Bass to compile code for a T-800 Model 101 that could be harmful to humans.