Re:LokiOS. A new version of CP/M 2.2, written from Scratch
by karmakaze on Thursday March 02, 2023 @03:47AM
(#34993508)
Oh yes, you're right! I'd forgotten some of how things got finalized. I started using the Atari 520ST with pre-release CP/M-68K docs and software before settling on GEMDOS/TOS. It was all in a bad state with a literal stack of paper given to me (rather than electronic docs) that only roughly corresponded to the state of the software so must have been in flux. Even the GEM parts were still being worked out. I recall using just the "Line-A"[0] graphics calls which were I believe 000a traps that were ROM calls to routines before getting access to higher level GEM graphics support.
There's mention of CP/M-68K and TOS with info on the Atari 130ST/260ST[1] (which also happened to have 512KB). I do recall later getting the OS in ROM of later hardware so boots were quicker.
The source code for both CP/M 68k and GEMDOS are available these days and one can see that while some small bits are borrowed between them (the program loader, for example), on the whole it's a whole new source tree.
I believe parts of the GEMDOS sources did become the basis of what eventually became DR-DOS on the x86.