14 ms·
MicroVAX 78032
- klelatti 4y agoInteresting that it had roughly the same number of transistors as the 286 but appeared three years later but on a larger node size (so bigger die).
- chasil 4y agoThe VAX was a 32-bit CPU with an mmu, the 286 was not. UNIX variants on the 286 had severe limitations (64k max program size). VMS was built for a much bigger machine than a 286. The fab was also in-house. "It is DEC's first single-chip microprocessor implementation of the VAX ISA and DEC's first self-fabricated microprocessor... "The MicroVAX 78032 contains 125,000 transistors on an 8.7 by 8.6 mm (74.82 mm2) die that was fabricated in DEC's ZMOS process, a 3.0 µm NMOS logic process with two layers of aluminum interconnect."
- Koshkin 4y agoThe 286 was a curious little beast. It did have a sort of an MMU, and, according to Wikipedia, The CPU was designed for multi-user systems with multitasking applications…
- dfox 4y ago286 and for that matter even 386 has the segment-based memory protection mechanism that is somewhat reminiscent of Burroughs mainframes, GECOS and maybe AS/400. There are two giant issues with the idea: it does not work that well on 16b word system and it is totally incompatible with what most of existing code written in C expects. So with 386 Intel had combined that mechanism with traditional MMU and somewhat hack-ish method to turn all that of (reportedly because Microsoft wanted that for Windows/386)
- retrac 4y agoA few operating systems, mostly UNIX clones, did exist that specifically took advantage of 286 protected mode. The 286 has user and supervisor modes, and could address up to 16 MB of physical memory. In protected mode it still used 8086 style segmented addressing, but the segments were virtual.
- Eleison23 4y agoThe bittersweet fact is that when the 80386 came out, OS designers dispensed with segmentation altogether, because it was conceptually so much easier to just flatten out a single vast address space. So despite the fact that i386 was now capable of really useful and intricate segmented memory architecture, it was the unsegmented, flat virtual address space that won the race.
- klelatti 4y agoYes my first reaction was that the VAX would have been a much better architecture but Intel's manufacturing lead meant that it could churn out 286s (and of course 386s in 1985) at much lower cost. Interesting to compare them both with the ARM1 which was 32 bit (no MMU) but only used 25k transistors on a 3 µm process - and which was more powerful than VAX 11/780. So both powerful and cheap to make.
- chasil 4y agoI really don't understand why Acorn wasn't purchased outright as soon as the samples were back from the fab. I think DEC was the first third-party implementation with StrongARM. https://en.m.wikipedia.org/wiki/StrongARM https://en.m.wikipedia.org/wiki/StrongARM
- klelatti 4y agoYes I think you're right on StrongARM which was the most powerful ARM CPU for a long time. Eventually made its way to Intel I think. I think everyone eventually had their own RISC - IBM, HP, AMD, Intel (i960) plus MIPs and SPARC of course and a few others. Arm eventually got traction because of the business model and because they intentionally didn't go head to head with the Intel x86 juggernaut. It wasn't obvious for a long time that their model would work though.
- KerrAvon 4y agoIIRC, StrongARM was the basis for XScale, which Intel foolishly spun off. They could have had a good chunk of the smartphone market, or at least a viable path into it.
- loph 4y agoAfter the eastern bloc copied this chip, DEC engineers had a special message for the Russians: https://micro.magnet.fsu.edu/creatures/pages/russians.html https://micro.magnet.fsu.edu/creatures/pages/russians.html
- ananonymoususer 4y agoI cannot find any reference to this online, but your post reminded me of a similar message to the Russians from the same era. The roof of the Northrop plant in Hawthorne, CA (now SpaceX) had "Yeb Vas" written in some fashion so as to be visible only from the ISR satellites of the day. https://mymemory.translated.net/en/Russian/English/yeb-vas https://mymemory.translated.net/en/Russian/English/yeb-vas
- johnklos 4y agoIt's also mentioned by one of the designers here: http://simh.trailing-edge.com/semi/cvax.html http://simh.trailing-edge.com/semi/cvax.html
- allarm 4y agoThis is a meaningless phrase and it does not translate to anything meaningful in Russian. They should have done proper research before wasting time on this nonsense.
- retrac 4y agoThis might have been the crucial point, where DEC missed the microcomputer boat. In early 1985, the only full 32-bit single-chip processor that was generally available was the Motorola 68020. The Intel 386 would come out later that year. DEC was focused on the high end though. Much of the R&D was going into high-end designs with rack-sized arrays of ECL logic for the processors in their VAX mainframes and vector supercomputers, which they never sold very many of. The later CMOS NVAX design, when process shrunk, ended up being faster than the $1 billion ECL VAX 9000 line not long after it was introduced.
- convolvatron 4y agoyeah, thats true. the 9000 was a really lovely workhorse though.
- em500 4y agoIt seems like the repeating cycle of the industry is the low end "toy" computers eating the high end "real work" computers, first in volume, eventually also in performance, from mainfraim (IBM) -> mini (DEC) -> workstation (SUN) -> PC (Intel) -> phone (Apple/ARM). With the incumbents never learning from history.
- wrs 4y agoThey learn, they just can't usually do anything different. See Clayton Christensen's The Innovator's Dilemma. [0] [0] https://en.wikipedia.org/wiki/The_Innovator%27s_Dilemma https://en.wikipedia.org/wiki/The_Innovator%27s_Dilemma
- kristopolous 4y agoI wonder if these classic patterns still hold now that everyone competent has read these 1990s era books. I could be strongly biasing myself without realizing it but I think they've become less common except on really grand scales where no single industry player is big enough to really control things Here's a few I see: podcasts and YouTube are successfully attacking conventional television and radio Home recording studio equipment improvements have seriously been eating into studio time. Home audio improvements have made the high end less relevant Display technology improvements have made affordable displays eat into the high end market. I think transportation and energy are the next big ones; solar panels will be so cheap that they'll start to be integrated just about everywhere and smaller electric cars (under 1500lbs or so) will become so affordable that those who drive for pure function will start adopting them en masse
- ananonymoususer 4y agoI did some development on uVAX in 1989. Wrote a DECWindows app that did monitor & control of a distributed realtime system. DECWindows was slow, so it would get updated every 250ms, while the realtime stuff communicated to a proxy (via 10Mbps DECNet with a custom driver) every 20ms. All of the code was in 'C', but everything aside from the DECWindows stuff was running from ROM on embedded VAXELN. https://en.wikipedia.org/wiki/DECnet https://en.wikipedia.org/wiki/DECnet https://en.wikipedia.org/wiki/VAXELN https://en.wikipedia.org/wiki/VAXELN
- johnklos 4y agoWhile collecting VAXen is usually reserved for those with gratuitous amounts of free space and lots of cheap power, I'm happy to have the 78032's successor, the CVAX SOC, running in my datacenter (it's slow - be patient): http://vlc.zia.io/ http://vlc.zia.io/ It includes the 78034, the floating point unit, and up to 8K of L1 cache in a single CPU package. The "up to 8K" was because they'd keep CPUs if 5K or more of L1 worked. It's my little piece of this interesting history.
- emmelaich 4y agoSydney University (Basser CS) had a few 11/780s. It may have run AUSAM, a modified 6th edition.[0] It was a rush to go from sharing one with 40 other students to my first job where I had a microvax all to myself! [0] https://www.tuhs.org/cgi-bin/utree.pl?file=AUSAM https://www.tuhs.org/cgi-bin/utree.pl?file=AUSAM
- actually_a_dog 4y agoYeah, that brings back memories. My college ended up getting a MicroVax while I was there... to replace the PDP-11/70. The 11 is one of my favorite machines due to the ISA. The MicroVax was just not the same. I'll grant that this is mostly due to nostalgia than technical merit, but, still... not the same.