Can it run Doom? Or NetBSD? or whatever people would normally run on a PC?
Megaprocessor – A micro-processor built large (2016)
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Re: Megaprocessor – A micro-processor built large (2016)
#82Re: Megaprocessor – A micro-processor built large (2016)
#83Re: Megaprocessor – A micro-processor built large (2016)
#84I'm astonished it's running Windows !
Re: Megaprocessor – A micro-processor built large (2016)
#85Earlier quoted context omitted.
In that case, if you want a somewhat entertaining very-high-level overview of what would need to be done, then there's a manga that showed this off a few chapters ago, it's called Dr. Stone. What stuck with me the most was that the purity needed for the silicon used in processors was absurdly high, so much so that they couldn't quite do that just yet, so they made a processor out of parametrons and used magnetic core…
Dr. Stone is great but I also found it to be a bit too hand-wavy. In real life you can't just build steam engines with a small village worth of labor + a "master craftsman". Mining, transporting, and refining iron ore alone is a huge task that could easily consume every drop of the village's labor resources and still not produce much iron. Fuel is also a huge task. Unless you have a high quality coal mine nearby, you…
IIRC a key obstacle why steam engines were not used earlier despite the concept being known for at least a millenium was the requirement for quite advanced metallurgy - you can make a nifty proof of concept from copper or iron, but a useful steam engine needs to be (a) relatively high pressure and (b) large, so you can do it only if you can reliably and cheaply make large quantities of decent steel. If you can't make large quantities of steel, your steam engine doesn't work; if your steel-making process has unpredictable results, then your boiler blows up at a weak spot, and if that steel is expensive, you're better off having the same people work a literal treadmill instead of making a steam machine.
Re: Megaprocessor – A micro-processor built large (2016)
#86Earlier quoted context omitted.
We could use vacuum tubes instead of transistors. (I googled this to make sure I wasn't misremembering what I read 40 years ago in an already outdated book at the library and I was suddenly filled with a sense memory of the smell of the interiors of old electric appliances loaded with tubes and dust.)
Yes...there were a couple of generations of what we would recognize as vaguely 'modern' computers (say...roughly ENIAC to the IBM 704/709) built completely out of stuff that looked like this: http://www.righto.com/2018/01/examining-1954-ibm-mainframes-...
Yes, that was the first all-electronic generation after the very earliest relay designs.
They were shockingly unreliable and incredibly expensive. Tubes have a very low mean time between failure, so any design that uses tubes exclusively can't work for more than short periods without breaking down - possibly minutes, maybe hours, probably not days, and absolutely not months or years.
And each failure means a cycle of fault finding, which can take hours or days in turn.
As a technology it sort of works in a prototype way - you can get some work done until you can't. But the unreliability means it's qualitatively different to a modern laptop or server farm.
The wonderful thing about integration on silicon is that it's the opposite - it's incredibly reliable, as long as you keep the thermals reasonable.
Re: Megaprocessor – A micro-processor built large (2016)
#87I often wondered i could build some sort of general computing machine if we were pushed back to the dark ages or something. I guess you have to define exactly at what level of technological achievements we were pushed back to. But with the knowledge we have today, and without ICs (or advanced manufacturing facilities) and only "simple electronics" (whatever that would be) if this would be possible. Fun stuff to think…
I mean, you can apparently trick swarms of crabs into being logic gates. https://phys.org/news/2012-04-scientists-crab-powered.html
Re: Megaprocessor – A micro-processor built large (2016)
#88If the ISA is sufficiently efficient, 8kHz is fast enough to run interpreters. An 8kHz can be useful as a calculator, running thing similar to FORTRAN and, if is has suitable I/O, maybe run a BASIC or CHIP-8 interpreter.
I'm curious what is the significance of 8kHz for running an interpreter? Am I missing something obvious?
Re: Megaprocessor – A micro-processor built large (2016)
#89The quality of not only the product, but the accompanying explanations is outstanding. I think it's a work of art, because not only is it visually impactful (especially at 1Hz, as in the demu), it also uses the medium to convey an idea that would be difficult to convey in any other way.
I'm interested in making (stochastic) algorithms fast, which always seems to eventually lead back to looking at code in compiler explorer. The extent of my knowledge there is basically "short assembly good, long assembly bad". But I've always lacked some "tactile" feeling (for lack of a better phrase) for what a register like "eax" or "rax" is. I hope that learning more about the megaprocessor might help get a glimpse of this.
Re: Megaprocessor – A micro-processor built large (2016)
#90Can it run Doom? Or NetBSD? or whatever people would normally run on a PC?
It seems to have an address width of 16 bits, there's no mention of a memory management unit, and the website lists its RAM size as 256 bytes, so I'm going to say no, regardless of speed.
The RAM size is of course the most limiting out of those three, but even if it were larger (and one could somehow build it without resorting to integrated circuits), you'd probably run into problems with the other fundamental limits if you wanted fancy things like memory in the order of megabytes.
Of course that's not the point, though, because building an entire general-purpose CPU from scratch at such a human-visible scale and from basic components is a feat in itself.