I'm moving this conversation to avoid derailing the other thread any further.

I know about CP/M because I'm interested in computer history. I wish it were available for the 6502 because it may have changed computer history as we know it. Imagine the Apple II and Commodore VIC-20 and 64 running on the same operating system.

Jeanette Isabelle

CP/M is/was available for the 6502 and the C64 and such, but I think it suffered from the same timing as the rest.

CP/M was becoming the standard along with the s-100 bus around the time the IBM PC and the commodore's and Atari's were being announced. So the 8080/8088/8086 architecture got a boost in the s100 and CP/M world because of expectations on the IBM PC release. IBM was one of the bigger names in business so it carried a lot of weight. It was easier to post CP/M 808x code to the MS/DOS and 8088 in the PC so you had that whole forward compatibility in their favor. So while CP/M could run on the 6502 (and 6800 and 68000, etc) there were less applications available than there were for the Intel cpu based CP/M's.

There was a cp/m cartridge for the C64 which contained a z80 so you could run more of the cp/m software (the z80 for those that don't know was an clone and extension of the intel 8080 so it was compatible).

The s100 bus timing was also based around the 8080/8088/8086 architecture so it was a little more work to make the 6502/6800/68k work with it and IBM's PC was mostly a copy of the s100 bus so designs could be adapted easily. The commodores and atari's expansion were not the same as the s100 so it took more work to interface with them. Plus RS-232 to terminals was still used a lot and while commodore and atari had their own serial ports they were not rs-232 standard and there fore needed extra hardware to utilize a company's existing terminals.
If Commodore and Atari had hardware closer to 8080/8088/8086 and s100 they might have had it further into the business market.

There have been a couple of CP/M clones, but CP/M was never written for the 6502.

Jeanette Isabelle

I did one project design using CP/M right out of college. I seem to remember feeding it gigantic floppies - 8 inch or something like that.

Shortly thereafter, a few years probably, I switched to Unix System V when it was released publicly. I was indeed working for AT&T, Western Electric, Bells Labs at the time - bumped around a lot, then bumped to Lucent and then Avaya in later years (retired now). There were a few Unixes prior to System V that we had internally, but I didn't use those.

I don't remember much about CP/M, other than recognizing the name as something I once used way in the past.

This thread reminds me of John Titor.
https://www.ebaumsworld.com/articles/a-look-back-at-john-titor-the-time-traveler/86070404/
-Blast (from the past...or future?)

I wonder if Mr. Titor had the presence of mind to pick up a copy of the 2036 Wall Street Journal before he came back to 1975.