[Simh] Operating Systems with Sources

[Bob Supnik]

I know of at least the following additional assembly language operating 
systems that have sources, mostly on Bitsavers:

1. OS/8 - PDP-8 assembly language
2. XVM/DOS-15 - PDP-15 assembly language
3. CAPS-11 - PDP-11 assembly language
4. TSS/8 - PDP-8 assembly language
5. ADSS-9/15 - PDP-9/15 assembly language
6. RSX11C - PDP-11 assembly language
7. XVM/RSX-15 - PDP-15 assembly language
8. IBSYS - IBM 7094 assembly language
9. CTSS - IBM 7094 assembly language
10. OS/32 - Interdata 32b assembly language
11. SDS940 timesharing - SDS 940 assembly language
12. ITS - PDP-10 assembly language

Not in assembly language, but quite compact, is an early version of 
Burroughs MCP for the B5500, which runs on the various B5500 simulators.

/Bob