Re: UNIBUS FTGH: EMM / CMU MICRORAM memories
> On Sep 17, 2019, at 8:17 AM, Stefan Skoglund wrote: > > mån 2019-09-16 klockan 11:17 -0700 skrev Guy Sotomayor Jr via cctalk: >> >> And that’s just the HW. Hydra (the OS that ran on C.MMP) was a >> capability based system (so you needed the proper capability to do >> anything). I recall at one point the grad student who was doing work >> on the file system, “lost” the root capability to the file system…so >> it was no longer possible to create new file systems. >> >> > > Which also means that for boot-strap you need to create a correct fully > populated binary dump of all the file system in the system. > A dump which is sane which regards to capabilities and user > capabilities > > It is a little like kick-starting a database system ie writing the > system database (pg_system) into such a state that is it possible to > correctly run for example: > --- > create tablespace 'stefan'; > create schema 'pg'; > --- > and so on… > The problem (and I’d be thrilled to be wrong) is that the probability of having a binary dump of Hydra is 0 for small values of 0. Part of the issue is that the C.MMP has a few RP06 drives (4-6?). If it were ever saved, it would have to be to 9-track tapes and I don’t recall any sort of backup facilities. The RP06 packs *might* still be around but I wouldn’t hold out too much hope for them either. TTFN - Guy
Re: UNIBUS FTGH: EMM / CMU MICRORAM memories
mån 2019-09-16 klockan 11:17 -0700 skrev Guy Sotomayor Jr via cctalk: > > And that’s just the HW. Hydra (the OS that ran on C.MMP) was a > capability based system (so you needed the proper capability to do > anything). I recall at one point the grad student who was doing work > on the file system, “lost” the root capability to the file system…so > it was no longer possible to create new file systems. > > Which also means that for boot-strap you need to create a correct fully populated binary dump of all the file system in the system. A dump which is sane which regards to capabilities and user capabilities It is a little like kick-starting a database system ie writing the system database (pg_system) into such a state that is it possible to correctly run for example: --- create tablespace 'stefan'; create schema 'pg'; --- and so on...
Re: UNIBUS FTGH: EMM / CMU MICRORAM memories
There were only 2 11/45s that I knew of. The first was the “front end” that sat in front of all of the terminals and allowed connection to the various 10s (at the time there were 3: 2 KA10s and a KL10), C.MMP and CM*. The other 11/45 ran the XGP... They had moved on to a Xerox 9700 and DECSYSTEM-20s behind Micom port selectors by the time I first rolled up there in 1984. CS still had a cluster of PERQs in Wean Hall. Not too long after that, the DECSYSTEM-20s were decom'd, and the old terminal clusters were converted over to IBM PCs, Macs, and IBM RT Andrew workstations. --FritzM.
Re: UNIBUS FTGH: EMM / CMU MICRORAM memories
11/40’s were pretty ubiquitous at CMU when I was there and at least as far as I could tell, were all configured pretty much the same (in that they all had custom writable control store). I personally dealt with 3 different sets of 11/40s: A single 11/40 with WCS that I used for doing some image processing work 2 11/40’s tied together with a prototype of C.MMP’s cross point switch C.MMP (16-way PDP11…I saw it running with 4 11/20s and 12 11/40s). At the end the 11/20s were removed and just the 11/40s remained. There were only 2 11/45s that I knew of. The first was the “front end” that sat in front of all of the terminals and allowed connection to the various 10s (at the time there were 3: 2 KA10s and a KL10), C.MMP and CM*. The other 11/45 ran the XGP (Xerox Graphics Printer)…granddaddy of laser printers so that we could get “high quality” output (versus line printer). TTFN - Guy > On Sep 16, 2019, at 2:27 PM, Fritz Mueller via cctalk > wrote: > > First off, I've had a couple of follow-ups on these units, so they are spoken > for at this point. > > The member with first dibs has also offered to scan the docs and see that > they make their way to Al. > > I was wondering if these were c.mmp cast-offs? Guy: I encountered these in > the CMU computer club hardware room (Doherty Hall basement, I think?) circa > 1986. There were a couple of '11/40s adjacent, and those did have some sort > of custom writable control store cards. > > The computer club was cleaning house, so I hauled off an '11/45 with CPU > spares that looked pretty stock, the aforementioned memory units, and a rack > mount Tek 'scope (about all I could convince my friends to help me haul off > campus at the time :-) > > Not sure what ever happened to the rest of the equipment that was down there. > I know they had a couple of working Altos, on a thick net segment with the > old vampire transceivers that had the little round glass windows in an > aluminum box. And what must have been parts of an earlier PDP (I remember a > smallish teletype bolted on to a piece of white Formica desktop.) > > --FritzM. >
Re: UNIBUS FTGH: EMM / CMU MICRORAM memories
First off, I've had a couple of follow-ups on these units, so they are spoken for at this point. The member with first dibs has also offered to scan the docs and see that they make their way to Al. I was wondering if these were c.mmp cast-offs? Guy: I encountered these in the CMU computer club hardware room (Doherty Hall basement, I think?) circa 1986. There were a couple of '11/40s adjacent, and those did have some sort of custom writable control store cards. The computer club was cleaning house, so I hauled off an '11/45 with CPU spares that looked pretty stock, the aforementioned memory units, and a rack mount Tek 'scope (about all I could convince my friends to help me haul off campus at the time :-) Not sure what ever happened to the rest of the equipment that was down there. I know they had a couple of working Altos, on a thick net segment with the old vampire transceivers that had the little round glass windows in an aluminum box. And what must have been parts of an earlier PDP (I remember a smallish teletype bolted on to a piece of white Formica desktop.) --FritzM.
Re: UNIBUS FTGH: EMM / CMU MICRORAM memories
I don’t know. It would be hard to replicate because of the custom HW and the custom uCode that ran on the 11/40s. I even think that the 11/20s were modified as well. So trying to figure that out would be “interesting”. ;-) There is documentation on bitsavers that covers the custom uCode HW for the 11/40s. The MMU as I recall was also radically different than what was standard on 11/40s (and non-existant on 11/20s…the 11/20 changes started to get to be so large, I believe later on they just ditched the 11/20s and C. was just all 11/40s) to allow for really large memory spaces…I don’t recall what the maximum possible memory on C. was, it did have 1.2MB while I was there. And that’s just the HW. Hydra (the OS that ran on C.MMP) was a capability based system (so you needed the proper capability to do anything). I recall at one point the grad student who was doing work on the file system, “lost” the root capability to the file system…so it was no longer possible to create new file systems. Since C.MMP was a “one off” system, don’t expect (even if the SW survives) that there’s an “installation guide”. ;-) It was pretty organic. Last and not least, all of the code was either PDP-11 assembler or BLISS-11. It was all cross built from the (heavily) modified TOP-10 systems that the CS department was running. Hydra did a number of things that eventually lead to Accent and then Mach (which portions are still in use in the guts of OS X). It was what we would call today a microkernel system in that the kernel was the only thing that ran in privileged mode. Everything else were user processes (file system, drivers, terminal system, etc). As I said, it was a capability based system, so to use something you needed to have a capability to it (files didn’t have Unix style permissions…if you had a capability to a file that capability determined what you could do to the file). It had a number of reliability traits: it could detect failures in HW and in SW and restart the appropriate failed item. In the case of CPUs and memory, it could “wall off” the failed component can cause diagnostics to be run to either isolate the problem further or determine that the failure is no longer present. TTFN - Guy > On Sep 16, 2019, at 10:59 AM, Paul Koning wrote: > > > >> On Sep 16, 2019, at 1:52 PM, Guy Sotomayor Jr via cctalk >> wrote: >> >> The only thing that I believe would have used these would have been C.MMP. >> It had 1.2MB of memory on it when I was there. >> >> TTFN - Guy > > It's been a long time since I've heard that reference. Did any of that > software get preserved? I wonder how hard it would be to make SIMH handle it. > > paul >
Re: UNIBUS FTGH: EMM / CMU MICRORAM memories
> On Sep 16, 2019, at 1:52 PM, Guy Sotomayor Jr via cctalk > wrote: > > The only thing that I believe would have used these would have been C.MMP. > It had 1.2MB of memory on it when I was there. > > TTFN - Guy It's been a long time since I've heard that reference. Did any of that software get preserved? I wonder how hard it would be to make SIMH handle it. paul
Re: UNIBUS FTGH: EMM / CMU MICRORAM memories
The only thing that I believe would have used these would have been C.MMP. It had 1.2MB of memory on it when I was there. TTFN - Guy > On Sep 16, 2019, at 10:45 AM, Al Kossow via cctalk > wrote: > > I would be interested in putting up the later docs > I wonder if Guy remembers what these were used for at CMU > > On 9/16/19 10:19 AM, Shoppa, Tim via cctalk wrote: >> The Microram was a multipurpose solid state memory chassis sold by EMM >> (Electronic Memories and Magnetics) with what we called later in the 1970's >> a "personality board" that plugged it into each different CPU's backplane. >> They sold a similar system (maybe even plug compatible at some level) with >> core planes under "Micromemory" brand name. I see we already have a "emm" >> directory in bitsavers with docs about some of their core products. >> >
Re: UNIBUS FTGH: EMM / CMU MICRORAM memories
I would be interested in putting up the later docs I wonder if Guy remembers what these were used for at CMU On 9/16/19 10:19 AM, Shoppa, Tim via cctalk wrote: > The Microram was a multipurpose solid state memory chassis sold by EMM > (Electronic Memories and Magnetics) with what we called later in the 1970's a > "personality board" that plugged it into each different CPU's backplane. > They sold a similar system (maybe even plug compatible at some level) with > core planes under "Micromemory" brand name. I see we already have a "emm" > directory in bitsavers with docs about some of their core products. >
Re: UNIBUS FTGH: EMM / CMU MICRORAM memories
The Microram was a multipurpose solid state memory chassis sold by EMM (Electronic Memories and Magnetics) with what we called later in the 1970's a "personality board" that plugged it into each different CPU's backplane. They sold a similar system (maybe even plug compatible at some level) with core planes under "Micromemory" brand name. I see we already have a "emm" directory in bitsavers with docs about some of their core products.
