[johndoe0815]

I don’t want to spoil your efforts, but I think the source is already online: https://github.com/option8/Altair-BASIC

[pdw]

There's a difference between the original source code and an annotated disassembly, even for assembly code.

[ta988]

This would be particularly useful to reverse engineer the macros.

[djmips]

It's good to check against.