4 ms·

CP/M could probably be fairly described as "heavily inspired" by the likes of TOPS-10, right down to borrowing some command names and some architectural ideas.

by retrac 5y ago

CP/M could probably be fairly described as "heavily inspired" by the likes of TOPS-10, right down to borrowing some command names and some architectural ideas. DOS 1.0 could probably be fairly described as a CP/M clone -- it was intended to be binary compatible basically, such that translated (perhaps automatically - the 8086 had similar compatibility goals) 8080 CP/M programs would run directly on DOS without much if any change.

TheOtherHobbes 5y ago
The PDP-10 - and TOPS-10 - were also used by Gates and Allen (and Davidoff) to write their version of BASIC. The lineage is more like OS-8 -> TOPS-10 -> CP/M -> DOS, although TOPS-10 did a lot more than CP/M etc because it was running on a small mainframe and not a micro. PDP-10s were also one of the foundations of ARPANET. And also used in early AI research. And also an influence on RMS. There was also a separate TOPS-20 lineage. TOPS-20 was the successor to TOPS-10 and (more or less) the anti-UNIX. It was designed to be as friendly as possible with command completion and other niceties like versioning and a kind of trash can - although it was quite verbose and had some strange command names of its own. (Like EXPUNGE.) Some of the philosophy of TOPS-20 made it into VMS. Cutler famously hated UNIX, but by the time he was done with NT the remains of VMS had been thoroughly Microsofted and it was hard to see any of the TOPS-20 lineage left in the UX. DEC shot itself in the kneecaps when it killed the PDP-10 line in 1983 and went all-in on the VAX. The VAX was a perfectly fine computer, but culturally it wasn't in the same space. PDP-10s were almost proto-Macs in the mainframe market - very popular with academics and creative researchers. The VAX felt more like a functional but unexciting proto-PC product. A lot of PDP-10 customers - and not a few PDP-10 engineers and developers - never forgave DEC for the move.
- skissane 5y ago
  > The lineage is more like OS-8 -> TOPS-10 -> CP/M -> DOS, although TOPS-10 did a lot more than CP/M etc because it was running on a small mainframe and not a micro. Gary Kildall had experience with a bunch of different DEC systems, definitely PDP-8s running OS/8 and PDP-11s running RT-11, he may have had some experience with PDP-10s as well. I would say he more took ideas from DEC operating systems in general rather than copying any one of them in particular, but if people want to cite particular ones, OS/8 and RT-11 are mentioned more often than TOPS-10. He also used IBM VM/CMS at the Naval Postgraduate School, which is arguably where CP/M gets drive letters from – CMS uses single letters to identify disks, DEC operating systems generally used multi-character device names like DL0: or RKA0: instead. > Some of the philosophy of TOPS-20 made it into VMS. Can you give a specific example of this? VMS was mainly influenced by RSX-11. What did it get from TOPS-20 that it didn't get from RSX-11?
- pinewurst 5y ago
  I don’t think DEC had much choice other than to kill the PDP-10 at that point. It was obvious that the non-legacy software world wasn’t a 36-bit one and never would be again. It was obvious it was taking increasingly incompatible hacks to extend the base 18-bit memory addressing (various combinations of magic segments). And while some may disagree, it wasn’t easy to make that architecture fast, hence the long standing performance plateau (the version codeveloped w VAX8600 never fully worked and XKL is only a proof of a faster system in much later technology but still much slower than other current CPUs). Nostalgia takes no prisoners.
- aap_ 5y ago
  > The lineage is more like OS-8 -> TOPS-10 -> CP/M -> DOS TOPS-10 predates OS-8
- deleted 5y ago
  [deleted]

by retrac 5y ago

TheOtherHobbes 5y ago

The PDP-10 - and TOPS-10 - were also used by Gates and Allen (and Davidoff) to write their version of BASIC. The lineage is more like OS-8 -> TOPS-10 -> CP/M -> DOS, although TOPS-10 did a lot more than CP/M etc because it was running on a small mainframe and not a micro. PDP-10s were also one of the foundations of ARPANET. And also used in early AI research. And also an influence on RMS. There was also a separate TOPS-20 lineage. TOPS-20 was the successor to TOPS-10 and (more or less) the anti-UNIX. It was designed to be as friendly as possible with command completion and other niceties like versioning and a kind of trash can - although it was quite verbose and had some strange command names of its own. (Like EXPUNGE.) Some of the philosophy of TOPS-20 made it into VMS. Cutler famously hated UNIX, but by the time he was done with NT the remains of VMS had been thoroughly Microsofted and it was hard to see any of the TOPS-20 lineage left in the UX. DEC shot itself in the kneecaps when it killed the PDP-10 line in 1983 and went all-in on the VAX. The VAX was a perfectly fine computer, but culturally it wasn't in the same space. PDP-10s were almost proto-Macs in the mainframe market - very popular with academics and creative researchers. The VAX felt more like a functional but unexciting proto-PC product. A lot of PDP-10 customers - and not a few PDP-10 engineers and developers - never forgave DEC for the move.

skissane 5y ago
> The lineage is more like OS-8 -> TOPS-10 -> CP/M -> DOS, although TOPS-10 did a lot more than CP/M etc because it was running on a small mainframe and not a micro. Gary Kildall had experience with a bunch of different DEC systems, definitely PDP-8s running OS/8 and PDP-11s running RT-11, he may have had some experience with PDP-10s as well. I would say he more took ideas from DEC operating systems in general rather than copying any one of them in particular, but if people want to cite particular ones, OS/8 and RT-11 are mentioned more often than TOPS-10. He also used IBM VM/CMS at the Naval Postgraduate School, which is arguably where CP/M gets drive letters from – CMS uses single letters to identify disks, DEC operating systems generally used multi-character device names like DL0: or RKA0: instead. > Some of the philosophy of TOPS-20 made it into VMS. Can you give a specific example of this? VMS was mainly influenced by RSX-11. What did it get from TOPS-20 that it didn't get from RSX-11?
pinewurst 5y ago
I don’t think DEC had much choice other than to kill the PDP-10 at that point. It was obvious that the non-legacy software world wasn’t a 36-bit one and never would be again. It was obvious it was taking increasingly incompatible hacks to extend the base 18-bit memory addressing (various combinations of magic segments). And while some may disagree, it wasn’t easy to make that architecture fast, hence the long standing performance plateau (the version codeveloped w VAX8600 never fully worked and XKL is only a proof of a faster system in much later technology but still much slower than other current CPUs). Nostalgia takes no prisoners.
aap_ 5y ago
> The lineage is more like OS-8 -> TOPS-10 -> CP/M -> DOS TOPS-10 predates OS-8
deleted 5y ago
[deleted]