[HN Gopher] The Soviet 8080 Processor - The 580
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The Soviet 8080 Processor - The 580
Author : protomyth
Score : 31 points
Date : 2021-03-11 15:20 UTC (7 hours ago)
(HTM) web link (www.cpushack.com)
(TXT) w3m dump (www.cpushack.com)
| elvis70 wrote:
| Site not accessible.
|
| The 8080. If I remember well, there was no instruction to adjust
| after BCD substraction (as with the Z80) So you had to do 9's
| complement the second operand and do an addition.
| api wrote:
| This is a great cautionary tale about why not to copy. Imagine if
| they'd taken their approaches from SECM and put them on an IC
| instead of copying the 8080... they probably would have had a
| superscalar chip when the West was just shipping 8-bit in-order
| cores.
| flohofwoe wrote:
| On the contrary, this is a great tale of why reverse-
| engineering standard technology makes sense (if you can't buy
| it at least, which the East couldn't because of the COCOM
| embargo).
|
| If the Eastern hemisphere had developed their own computer
| technology, everything I had learned as kid would've been
| worthless after the Wall fell. But since East Germany was Z80
| (and towards the end, 8086) land, I could more or less
| seamlessly continue with my self-education ;)
|
| I've heard that East German engineers liked the Zilog Z8000 a
| lot more than the Intel x86 architecture, but pragmatically it
| made a lot of sense to adopt the same standards that had won in
| the West already.
| api wrote:
| Meh. I grew up with x86 and it was trivial for me to get into
| ARM and even using ARM NEON, etc. Computers are computers and
| understanding of them is largely transferrable.
| [deleted]
| anonymousiam wrote:
| Another reason to not copy what the west was doing was the
| deliberate crippling of early systems. It's difficult to find
| this information on the web, but I recall that the early IBM
| PC/AT machines ran at 6MHz and contained BIOS code that
| prevented them from booting if they were clocked any faster.
| (Later versions ran at 8MHz.)
|
| The reason was to prevent people from buying IBM PC/AT machines
| instead of IBM RISC 6000 workstations.
| jecel wrote:
| I think early 286 chips didn't go up to 8MHz. The IBM RT PC
| (the ancestor of the 6000) was only introduced 2 years after
| the AT:
|
| https://en.wikipedia.org/wiki/IBM_RT_PC
| mhh__ wrote:
| Don't forget that Tomasulo invented his algorithm in the 60s at
| IBM - e.g. vaguely modern out of order execution
| fuoqi wrote:
| Yeah, I also read that the order to copy CPUs developed by the
| West has greatly demoralized Soviet engineers working in this
| field. You should learn from your competitors and build on top
| of that.
| cafard wrote:
| Dijkstra wrote somewhere that the Cold War was effectively
| over when the Soviet Union decided to copy the IBM 360.
| MichaelMoser123 wrote:
| don't know, developing the s360 line cost ibm 5 billion $
| [1] (that was quite a bit of a moon shot, given that the
| moon program has cost 25 billion $ [2]). Maybe it would
| have cost them less if the s360 instruction set had a
| stack, but who knows. In any event this price tag pursuaded
| them to clone the whole thing.
|
| [1] https://spectrum.ieee.org/tech-history/silicon-
| revolution/bu... [2] https://money.com/apollo-11-moon-
| mission-cost/
| Longlius wrote:
| The west had superscalar computers around a decade later but
| superscalar designs didn't make their way into ICs until the
| 90s for the simple reason that chip fabrication technologies
| simply weren't there for making high-density ICs. The
| complexity and cost of the SECM was likely one of the major
| reasons it was shelved in favor of more straightforward in-
| order processors. Your alternate history would be predicated on
| several decades of semiconductor fab advancement happening in
| just one or two within the Soviet Union, which, regardless of
| where you stand in terms of ideology, simply isn't a realistic
| assessment of the facts.
| pinewurst wrote:
| There's a strange romanticization of the BESM-6 in the West. I
| cringe when I read the "it took us 30 mins and them 1 min"
| anecdote - given that there are no comparables here beyond the
| vague result.* There's another similar one comparing BESM-6 to
| CDC6600 with the claim that if the former ran at the same clock
| speed as the latter, it'd be comparable. If a horse ran at Mach
| 2, it'd be comparable with an F-15.
|
| *Who knows what crud code we were running on some IBM thing in
| what language, using what algorithm, to what level of precision?
| Or what the BESM-6 was running?
| thedanbob wrote:
| It's not necessarily the West romanticizing it in this case:
|
| > This article is largely from guest author Vladimir Yakovlev,
| translated from Russian, and edited/expanded by me.
| neonate wrote:
| https://archive.is/lJirU
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