Modern, single-binary assemblers — and, in time, disassemblers — for the retro CPUs of the 198x era. One consistent toolchain across machines, built to still run in ten years.

The period assemblers are dead-OS binaries: you need DOSBox or a full emulator just to invoke them. The modern community tools mostly work, but they're scattered — a different program, syntax, and build dance per machine. Asm198x aims to be one statically-linked, cross-platform, documented toolchain that spans the family's CPUs, with each backend source-compatible with its machine's established dialect so existing code still assembles.

It's early days, and built in the open.

• asm198x — the assembler workspace: the shared instruction-set spec and the assembler engine + CLI. 6502 first.
• docs — documentation: the spec format, per-machine dialect references.

A sibling project to retro-computing curriculum and emulator work that share a hardware-reference layer. Assemblers, emulators, and teaching — three views of the same machines.