In the late 70’s John Walker was operating Marinchip Systems, a company marketing S-100 computers based around the TI 9900 chip and associated software. He discussed that on these pages:
https://www.fourmilab.ch/documents/marinchip/
Over the past months I have as a tribute curated John’s Marinchip software into an accessible archive, including an emulator for a Marinchip-like computer system. The material can be found here:
https://gitlab.com/marinchip
All the executables mentioned in the manuals are there, and source code for some of the key packages – including the two operating system kernels. Missing is source code for the early tools (the line editor, assembler and linker), for the SPL and QBasic compilers, and for Interact – the precursor to AutoCAD.
If you are interested in this era of John’s work or have material in the attic relating to Marinchip Systems’ software and hardware, let me know.