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Fascinating story. But I doubt anyone could have made a KL-10 on a board in 1975. A TTL implementation would have been difficult to squeeze into a small space,

Fascinating story. But I doubt anyone could have made a KL-10 on a board in 1975. A TTL implementation would have been difficult to squeeze into a small space, and a VLSI implementation was at least a decade away. In fact there was a short-lived project called Minnow which was supposed to put a KL-10 on a desk, but it was overtaken by VAX - much like the Jupiter super-KL-10 project, which never got past the design notes and emulation stage. LSI-11s did end up in small boxes, so that wasn't the problem. The problem was that Olsen didn't have a vision for commodity personal computing. And to be fair not many people did in the 70s. He seems to have been a very 1950s corporate kind of manager, and couldn't imagine computing outside of technical and corporate settings. DEC's culture was geared to selling to corporates and academia and trying to compete with IBM, not with smaller startups. So when DEC did eventually try to make hardware that could compete with PCs they tried to sell it to their usual customers instead of finding new markets. And that... didn't work. Apple meanwhile had worked out that you needed a national dealer network with stores and hands-on demos all over the country. And plenty of approachable PR and ad spend. That was really what made Apple stand out from the competition, and that kind of marketing, to users who didn't work in big offices, factories, and research labs, and didn't have degrees, was unimaginable at DEC. I'm fascinated by DEC as a company. There was some incredible world-leading engineering and a progressive culture, but the vision seems to have got stuck on a peg in the 70s, kept it together in the 80s because VAX was already in place, but couldn't deal realistically with the 90s. Gordon Bell has said that Olsen never quite understood what VLSI implied culturally and socially - never mind technically and financially. There's an apocryphal story about someone handing Olsen one of the pre-Alpha VAX-on-a-chip designs and he has a very polite mini-meltdown when he realises that it literally outperforms the top water-cooled mainframe ECL VAX hardware - for just a few hundred dollars, instead of a couple of million.

Throwawayaerlei 6y ago
the Jupiter super-KL-10 project, which never got past the design notes and emulation stage. The scuttlebutt in the Boston area at the time was that DEC was frantically trying to debug one or more ECL prototypes, engineers working in 3 shifts, 24 hours a day. Further, that the head designer was poached from the IBM mainframe world, and did not understand what made a PDP-10 fast. In particular, unlike the KL-10 which had a 72 bit wide FPU, its was 36 bits wide, which after the lateness was the final straw for its viability in the marketplace. And people marveled that DEC was willing to throw away a $100 million a year business, $275 million today, supposedly a lot of dedicated PDP-10 and Decsystem-20 shops declined to move to the Vax, which they could predict would be a bad long term move. All this is at the Nth hand rumor level, but from some people who were very interested in the architecture's fate, some with purchasing influence if not capability. It sounds like you have some better sources. The Olsen never groked VLSI tidbit is fascinating, and I suppose credible.
- mr_wook 6y ago
  The KC-10, which you were referring to, had one (long) shift of very dedicated engineers, and the lead engineer came from ITEL which made IBM compatible mainframes. He had (an easy to understand) fundamental misunderstanding about PDP-10 architecture which impacted functionality, not performance, as the KC-10 was going to be the fastest machine DEC ever made. He caught mono, and found his misunderstanding while stuck at home with the hardware manuals. The thing that actually killed the KC-10 (and the KS-10 desktop successor) was the VAX, which Gordon Bell went all in on.
rjsw 6y ago
> There's an apocryphal story about someone handing Olsen one of the pre-Alpha VAX-on-a-chip designs and he has a very polite mini-meltdown when he realises that it literally outperforms the top water-cooled mainframe ECL VAX hardware - for just a few hundred dollars, instead of a couple of million. There is a fair bit of history [1] written by the author of the SIMH emulator, Bob Supnik. The page on NVAX basically confirms your story. [1] http://simh.trailing-edge.com/dsarchive.html http://simh.trailing-edge.com/dsarchive.html
GeorgeTirebiter 6y ago
As far as pdp-10 on a board, I knew the LSI-11 was an 8-bit microcoded processor https://en.wikipedia.org/wiki/MCP-1600 https://en.wikipedia.org/wiki/MCP-1600 In fact, the "EIS/FIS" instruction set option was just another ROM available as an optional chip. And, given that my roommate was doing the KL-10 microcode, I had some idea how you could trade microcode space for actual hardware execution units. So, yes, my original idea was to use the LSI-11 (Western Digital) base chips with different / more microcode. Yes, it would have been slow. But it would have been a pdp-10. Years later, Gordon Bell told me that somebody had built a pdp-10 on a board. I think it may have been an internal project (not the KS10), a hack like the 'pdp-8 in a suitcase' that I saw in Maynard. I need to ask him. I, too, have difficulty understanding the killing of the pdp-10 line; what often goes unnoticed is the very high level of capability in Marlboro (vs e.g. Maynard). When I started as a co-op student, I wanted to work in Maynard with the pdp-11 folks, which I thought was the cat's meow. But wiser folks told me, "Hey, you should consider yourself special, as they are putting you in the pdp-10 group!" And of course they were right. So when DEC canceled the '20, they also -- effectively -- broke up the best / brightest concentration of computer geeks in the whole company. It's difficult to appreciate the pride the pdp-10 group took in their machines - after all, they were the machines for AI research and were the first machines on the ARPAnet. And, as anybody alive today knows, 32 bits isn't quite enough, but 36? nee 72? Ahhh... ;-) Ken was a very bright engineer. He used his engineering skills to 'engineer' DEC, I think. I asked him if he thought DEC was competing with IBM, he said "No, we serve different markets." I wish I remembered more about that conversation that day. DEC was only 18 years old at the time.

Throwawayaerlei 6y ago

the Jupiter super-KL-10 project, which never got past the design notes and emulation stage. The scuttlebutt in the Boston area at the time was that DEC was frantically trying to debug one or more ECL prototypes, engineers working in 3 shifts, 24 hours a day. Further, that the head designer was poached from the IBM mainframe world, and did not understand what made a PDP-10 fast. In particular, unlike the KL-10 which had a 72 bit wide FPU, its was 36 bits wide, which after the lateness was the final straw for its viability in the marketplace. And people marveled that DEC was willing to throw away a $100 million a year business, $275 million today, supposedly a lot of dedicated PDP-10 and Decsystem-20 shops declined to move to the Vax, which they could predict would be a bad long term move. All this is at the Nth hand rumor level, but from some people who were very interested in the architecture's fate, some with purchasing influence if not capability. It sounds like you have some better sources. The Olsen never groked VLSI tidbit is fascinating, and I suppose credible.

mr_wook 6y ago
The KC-10, which you were referring to, had one (long) shift of very dedicated engineers, and the lead engineer came from ITEL which made IBM compatible mainframes. He had (an easy to understand) fundamental misunderstanding about PDP-10 architecture which impacted functionality, not performance, as the KC-10 was going to be the fastest machine DEC ever made. He caught mono, and found his misunderstanding while stuck at home with the hardware manuals. The thing that actually killed the KC-10 (and the KS-10 desktop successor) was the VAX, which Gordon Bell went all in on.

rjsw 6y ago

> There's an apocryphal story about someone handing Olsen one of the pre-Alpha VAX-on-a-chip designs and he has a very polite mini-meltdown when he realises that it literally outperforms the top water-cooled mainframe ECL VAX hardware - for just a few hundred dollars, instead of a couple of million. There is a fair bit of history [1] written by the author of the SIMH emulator, Bob Supnik. The page on NVAX basically confirms your story. [1] http://simh.trailing-edge.com/dsarchive.html http://simh.trailing-edge.com/dsarchive.html

GeorgeTirebiter 6y ago

As far as pdp-10 on a board, I knew the LSI-11 was an 8-bit microcoded processor https://en.wikipedia.org/wiki/MCP-1600 https://en.wikipedia.org/wiki/MCP-1600 In fact, the "EIS/FIS" instruction set option was just another ROM available as an optional chip. And, given that my roommate was doing the KL-10 microcode, I had some idea how you could trade microcode space for actual hardware execution units. So, yes, my original idea was to use the LSI-11 (Western Digital) base chips with different / more microcode. Yes, it would have been slow. But it would have been a pdp-10. Years later, Gordon Bell told me that somebody had built a pdp-10 on a board. I think it may have been an internal project (not the KS10), a hack like the 'pdp-8 in a suitcase' that I saw in Maynard. I need to ask him. I, too, have difficulty understanding the killing of the pdp-10 line; what often goes unnoticed is the very high level of capability in Marlboro (vs e.g. Maynard). When I started as a co-op student, I wanted to work in Maynard with the pdp-11 folks, which I thought was the cat's meow. But wiser folks told me, "Hey, you should consider yourself special, as they are putting you in the pdp-10 group!" And of course they were right. So when DEC canceled the '20, they also -- effectively -- broke up the best / brightest concentration of computer geeks in the whole company. It's difficult to appreciate the pride the pdp-10 group took in their machines - after all, they were the machines for AI research and were the first machines on the ARPAnet. And, as anybody alive today knows, 32 bits isn't quite enough, but 36? nee 72? Ahhh... ;-) Ken was a very bright engineer. He used his engineering skills to 'engineer' DEC, I think. I asked him if he thought DEC was competing with IBM, he said "No, we serve different markets." I wish I remembered more about that conversation that day. DEC was only 18 years old at the time.