[HN Gopher] Megaprocessor - A micro-processor built large (2016)
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       Megaprocessor - A micro-processor built large (2016)
        
       Author : amadeuspzs
       Score  : 224 points
       Date   : 2021-11-18 11:14 UTC (11 hours ago)
        
 (HTM) web link (www.megaprocessor.com)
 (TXT) w3m dump (www.megaprocessor.com)
        
       | FpUser wrote:
       | Curious what factors limit clock to 8kHz.
        
         | sbierwagen wrote:
         | https://www.quora.com/How-is-transistor-density-related-to-c...
        
         | errcorrectcode wrote:
         | Worst case propagation delay.
        
           | FpUser wrote:
           | This does not make any sense. I can get way better delay /
           | frequency wise on long USB cables. Something here does not
           | compute.
        
       | jdkee wrote:
       | MOnSter 6502 for the curious.
       | 
       | https://monster6502.com/
        
         | mdp2021 wrote:
         | Beautiful.
         | 
         | Inspired by this great submission, I was instead at
         | http://visual6502.org/JSSim/index.html - 6502 simulator in
         | HTML5 with visual changes on the virtual circuitry.
        
           | LargoLasskhyfv wrote:
           | There is now https://github.com/floooh/v6502r as in
           | _remixed_.
           | 
           | Purposedly better, faster, and has Z80, too.
        
       | qwerty456127 wrote:
       | Can it run Doom? Or NetBSD? or whatever people would normally run
       | on a PC?
        
       | temeritatis wrote:
       | I 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 about!
        
         | galcerte wrote:
         | 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 memory. I
         | knew semiconductors had to be very pure, but it was a bit
         | discouraging to realize just how much effort it would take if
         | you started from zero.
        
           | sbierwagen wrote:
           | >the purity needed for the silicon used in processors was
           | absurdly high
           | 
           | Yes. Silicon wafers are cut from a monocrystalline boule, a
           | single flawless silicon crystal with no defects or
           | inclusions. A big chunk of silicon atoms, nothing else at
           | all. (Doping happens later) To the extent any physical object
           | can be called "perfect", a semiconductor wafer is perfect.
           | 
           | (Of course after manufacturing it will start picking up
           | embedded hydrogen and helium atoms from cosmic rays and alpha
           | particle background radiation.)
        
           | [deleted]
        
           | simp-in-a-box wrote:
           | Wow, no idea Dr. Stone was that hardcore. That sounds
           | watchable!
           | 
           | edit: didn't pay attention that you were talking about the
           | _manga_. That makes more sense. Sounds highly readable!
        
           | umvi wrote:
           | 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 have to create charcoal which is also very labor
           | intensive (see: https://www.youtube.com/watch?v=GzLvqCTvOQY).
           | I just can't fathom how Senku realistically makes processors
           | unless he has a nation state worth of labor at his disposal.
           | 
           | But yeah, it is a fun "what if".
           | 
           | "What if a super genius with the entirety of wikipedia in his
           | brain were sent back to the stone age? Could he rebuild
           | modern society?"
        
             | Jtsummers wrote:
             | At least with iron, you'd have the benefit of the existing
             | refined ore lying all around you in a post-apocalyptic
             | setting. There's little need for actually mining iron ore
             | anymore if your population has been reduced by 99% or more.
             | You can walk down any abandoned street and find sources of
             | iron and other metals. Now, there's still the refining
             | process (but it would be shorter from something already
             | processed) and fuel to contend with.
        
         | userbinator wrote:
         | Babbage's analytical engine comes close, and doesn't even use
         | electricity.
        
         | kens wrote:
         | Looking historically, you have a bunch of options for a pre-IC
         | computer; there were lots of pre-IC computers. Transistors, of
         | course, or vacuum tubes give you a useful computer. You can
         | build a computer from relays, but the performance is pretty
         | bad. Memory is also very important. Magnetic core memory is the
         | way to go if you don't have ICs. None of this is going to help
         | you if you went to the dark ages.
         | 
         | As far as mechanical devices, mechanical calculating machines
         | didn't arise until the late 1600s and weren't reliable for many
         | years. It's unlikely that you'd be capable of building a
         | mechanical computer until the industrial revolution. Note that
         | Babbage was unsuccessful in building his machines even in the
         | late 1800s.
         | 
         | If your goal is to build a Turing-complete machine of some
         | sort, even if totally impractical, you could push the date back
         | a lot. But that would be more of a curiosity than a useful
         | computer.
        
           | Joker_vD wrote:
           | For arithmetic, pinwheel calculator (aka "Odhner's
           | arithmometer") [0] is a pretty decent and reliable mechanical
           | device. You can even give it an electric motor for doing the
           | rotations for you and a numerical keyboard.
           | 
           | [0] https://en.wikipedia.org/wiki/Pinwheel_calculator
        
         | jhgb wrote:
         | On that note, I was wondering on several occasions whether it
         | would have been technologically possible to build neon lamp
         | logic circuits in Babbage's time. Aside from the problem of
         | building an air liquifier a few decades early, I don't see any
         | really major technological hurdles there. That would have
         | nicely solved his problems with mechanical manufacturing...
        
         | mkreis wrote:
         | You can even build a binary machine without electronics, have a
         | look here: https://en.wikipedia.org/wiki/Z1_(computer)
        
         | kohsuke wrote:
         | I forgot which book it was (maybe "the three body problem"?)
         | but there was a science fiction story where a Chinese king
         | makes his soldier act as a logical gate and his army becomes a
         | computer. I was like, wow, I didn't think about that, but it
         | totally makes sense!!
        
           | Sander_Marechal wrote:
           | There's an XKCD for everything :-) https://xkcd.com/505/
        
           | gpm wrote:
           | That is the three body problem, and while avoiding spoilers,
           | not exactly a Chinese king.
        
         | ezconnect wrote:
         | In the dark ages you can build gears. Gears can do arithmetic
         | and calculus.
        
           | dhosek wrote:
           | The catch is that there are tolerance issues. Doron Swade's
           | account of building the two existing Difference Engine #2
           | models
           | (http://www.amazon.com/exec/obidos/ASIN/0670910201/donhosek)
           | is a good example of where the challenges lie. It was _just
           | barely_ possible to do with 19th century technology. Physical
           | mechanisms deviate from theory by quite a bit.
        
             | ezconnect wrote:
             | Antikythera mechanism was built before the Dark Ages, he
             | just wanted to go back to the Dark Ages so he can do
             | precision work by that time, he can probably build a
             | battleship fire control system at that time.
             | 
             | edit: https://www.youtube.com/watch?v=gwf5mAlI7Ug
        
               | hypertele-Xii wrote:
               | Now he just needs to build a battleship to go with it!
        
         | 95014_refugee wrote:
         | Then the next question is; what would you _do_ with it?
         | 
         | You need a source of problems to solve, and until you've
         | bootstrapped the rest of society at least to the point where
         | something like high-resolution trigonometric tables, desktop
         | publishing, high-speed accounting, (for example) are needed,
         | the effort isn't going to keep you fed...
        
           | tyingq wrote:
           | I agree it wouldn't be high on the list, but I also imagine
           | there would be practical needs. Like command/control. So,
           | voice only radios first, but some sort of messaging that
           | doesn't need a live listener on the radio would then be a
           | nice next step. And that could be done with a simple
           | computer.
        
           | kjs3 wrote:
           | Calculate ballistics, like some of the original computers
           | were created for? Never too early post-apocolypse to start
           | the thinking about the next war.
        
         | deltaonefour wrote:
         | The first computing machines used relays which are
         | electromechanical mechanical switches. Current would flow into
         | an electric magnetic and it would magnetize a switch and close
         | a loop thereby switching something "on." By placing these
         | switches together into different configurations you could form
         | equivalent logic gates.
         | 
         | Sometimes insects or moths would get stuck in the relays which
         | would screw up the system. This is the origin of the word
         | "bug."
         | 
         | Prior to incorporating logic into electronics, computing
         | machines were hand cranked or motor cranked gear machines. See:
         | https://www.youtube.com/watch?v=fhUfRIeRSZE. The YouTube video
         | literally is a hand cranked portable calculator.
         | 
         | The world you envision has already existed.
        
           | agalunar wrote:
           | The use of the term "bug" in engineering predates automatic
           | computers by nearly a century; the Wiki article [1] on the
           | topic gives a pretty good summary of its history.
           | 
           | [1] https://en.wikipedia.org/wiki/Bug_(engineering)#History
        
           | [deleted]
        
           | hypertele-Xii wrote:
           | > The YouTube video literally is a hand cranked portable
           | calculator.
           | 
           | It can even do _square roots?!_ That 's amazing. And it fits
           | the palm of your hand!
           | 
           | Now we're down to specks of sand calculating so fast they
           | melt without cooling. Seriously wtf.
        
         | Koshkin wrote:
         | No need in electronics whatsoever - mechanical computing is a
         | sufficiently advanced engineering discipline, as, incidentally,
         | is fluidics!
         | 
         | https://en.wikipedia.org/wiki/Fluidics
        
         | 52-6F-62 wrote:
         | Good point!
         | 
         | I used to play that same thought experiment with more basic
         | utilities like my toaster with it's various settings and
         | electronic controllers. Then I was given a Dualit. No more
         | philosophical dilemmas!
         | 
         | Kidding aside, it's always staggering how far removed we really
         | are from operating on (humanly) first principles. Humbling.
        
           | adrianN wrote:
           | There are many people on the internet researching how basic
           | things can be made in a low-tech fashion. I particularly
           | enjoy https://simplifier.neocities.org/ for example.
           | 
           | But if you read those blogs you still notice the mind
           | boggling height of the giants whose shoulders the bloggers
           | stand on. Having access to simple chemicals like acids or
           | various salts for example is huge. I wouldn't even know where
           | to start if I had to bootstrap a highschool chemistry kit
           | starting with nothing but my hands and my knowledge.
        
             | sudosysgen wrote:
             | The Dr. Stone manga provides an interesting perspective on
             | how you'd bootstrap that chemistry kit.
        
               | adrianN wrote:
               | 219 chapters and ongoing. Whew. This confirms my
               | suspicion that bootstrapping is really hard.
        
         | magicalhippo wrote:
         | Relay computers are relatively simple to make, and require just
         | electromechanical relays.
         | 
         | Some semi-random examples
         | 
         | https://web.cecs.pdx.edu/~harry/Relay/
         | 
         | https://relaycomputer.co.uk/
         | 
         | Main issue is memory. Takes a lot of space to make any usable
         | about of memory out of relays.
        
         | TheOtherHobbes wrote:
         | First gen transistor computers often used standard functional
         | units - gates, flip flops, and such - packaged into small
         | modules with edge connectors and wired together with wire wrap
         | on a backplane. Like this DEC PDP-8.
         | 
         | http://www.oldcomputers.arcula.co.uk/files/images/pdp8104.jp...
         | 
         | It's fairly easy to design a computer like this.
         | 
         | Later TTL/CMOS designs replaced the packaged modules with much
         | smaller 74xx/40xx ICs.
         | 
         | You can make basic logic gates with just diodes and resistors,
         | but you need transistors for inversion, buffering, and a usable
         | flip flop.
         | 
         | That's probably the minimum level for useful
         | computing/calculating. If civilisation has ended and you have
         | no transistors you probably don't have the resources to make
         | glass valves either, so that's going to be a problem.
         | 
         | Of course there's always clockwork...
        
           | Koshkin wrote:
           | A famous example of a modular design is IBM's Solid Logic
           | Technology that was used in their System/360:
           | 
           | https://en.wikipedia.org/wiki/IBM_Solid_Logic_Technology
        
             | pavlov wrote:
             | These modules seem to be the primary influence on sci-fi
             | movie computer design, starting with HAL in "2001".
             | 
             | When sci-fi writers need to create some plot tension around
             | getting a computer either up and running or down and
             | disarmed, the characters will inevitably be
             | plugging/unplugging colorful modules at some point.
        
           | dhosek wrote:
           | 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.)
        
             | bashinator wrote:
             | We could use telegraph relays instead of vacuum tubes -
             | might be better reliability and repairability.
        
               | Koshkin wrote:
               | Except that mechanical contacts are the bane of all
               | things electrical. Vacuum tubes are lightyears ahead of
               | relays in this regard.
        
               | HeyLaughingBoy wrote:
               | Repairability, yes. Reliability, no.
        
             | kjs3 wrote:
             | 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-...
        
         | mburns wrote:
         | CollapseOS is a z80-based forth that is targeted at
         | bootstrapping computing from scavengable components in old
         | electronics.
         | 
         | https://collapseos.org/
        
       | zanethomas wrote:
       | I think the minicomputers of the 70s well-represent the halfway
       | point between there and what we have today.
       | 
       | At Basic Four Corporation I worked on systems built from 8"x11"
       | circuit boards. A CPU might consist of two such cards joined on
       | the front by a couple flat 50-pin cables and to the other
       | components by a backplane.
       | 
       | Disk Controller: 1 board Terminal controller: 1 board etc
       | 
       | https://www.ricomputermuseum.org/collections-gallery/equipme...
       | 
       | Would be interesting to see some enterprising soul recreate a
       | modern computer in such a form factor.
        
         | bitwize wrote:
         | I am unaware of many Hackernews who had even _heard_ of Basic
         | Four, let alone worked there! Did you know Chuck Milden?
        
           | zanethomas wrote:
           | If I did I don't remember him. :) How are you familiar with
           | Basic Four?
        
             | bitwize wrote:
             | Chuck was president of ICS, which was acquired by Basic
             | Four in like the mid-70s. I only met him long after, but he
             | told me stories. Including one about how he wheeled an
             | Apple II into the Basic Four boardroom and demonstrated it,
             | saying in effect "this is the future, and if you're not on
             | board with the microcomputer revolution you'll be left
             | behind". They decided to pass, and continue figuring out
             | ways to sell $50,000 hard disks to existing customers. And
             | that's why most of Hackernews hasn't heard of Basic Four :)
             | 
             | I do know that MAI ended up selling microcomputer based
             | products eventually, but by that time they were well into
             | day-late-dollar-short territory and would continue to lose
             | ground along with all the other minicomputer vendors like
             | PRIME that hardly anyone these days has heard of.
        
               | zanethomas wrote:
               | Basic Four was about 300 employees when I landed there
               | and having spent most of my time in manufacturing I
               | didn't rub elbows with upper management. Although they
               | did rub elbows with me once when they thought I was
               | stealing their operating system. But that's a whole
               | nother story. :)
        
       | marcodiego wrote:
       | If 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.
        
         | Maakuth wrote:
         | Alternatively it works if you are sufficiently patient.
        
       | tyingq wrote:
       | In the same space of using discrete components instead of ICs ,
       | the Monster6502: https://monster6502.com/
       | 
       | Note: Well, there are some quad transistor array chips, but that
       | seems still in the same spirit.
        
       | trasz wrote:
       | That giant slider pot to adjust clock speed is awesome.
        
       | osamagirl69 wrote:
       | The mega processor is one of my all-time favorite computers,
       | along with the Magic-1 https://homebrewcpu.com/
       | 
       | The megaprocessor is just absolutely wonderful in how it bridges
       | from 'here is a transistor, it lights an LED' to 'here is a
       | computer, it plays tetris'. I always struggled to unwind the
       | layers of abstraction in a modern computer from atoms in the CPU
       | to running python, but being able to just look at a bunch of
       | literal transistors (with LEDs on each gate!) wired up playing
       | tetris shows how a computer really works in such a profound and
       | awe inspiring fashion.
       | 
       | Magic-1 is sort of the next level higher complexity, where it is
       | made out of very simple TTL (most complicated chip function is
       | the ALU--a circuit I had to build as an EE undergrad out of or-
       | and and- gates) and it hosts a webpage. It currently seems to be
       | down, but you can see it on the wayback machine
       | https://web.archive.org/web/20210815180101/http://www.magic-...
       | 
       | I will never forget when I came across that site and realized
       | that I was interacting with a wirewrapped pile of ram and nor
       | gates over the internet. There was even a time when you could
       | telnet in and play some retro text-based adventure games, To this
       | day, the only time I have played Adventure was on Magic-1.
        
         | IanWard1 wrote:
         | Love this kind of build, so I'm working on a little breadboard
         | one myself https://www.youtube.com/IanWard1 similar to the Ben
         | Eater 8-bit CPU videos
         | https://www.youtube.com/watch?v=HyznrdDSSGM&list=PLowKtXNTBy...
         | (which are amazing and everyone should watch)
        
         | criddell wrote:
         | Charles Petzold's book _Code: The Hidden Language of Computer
         | Hardware and Software_ explains a computer from the ground up.
         | 
         | I don't know if the ideas still apply to modern computers, but
         | it's pretty cool understanding how things like addresses are
         | decoded and instructions are constructed and executed at the
         | gate level in a very basic microprocessor.
        
         | AnIdiotOnTheNet wrote:
         | I'm partial to the Gigatron[0] myself. Built entirely using a
         | mere 34 TTL ICs available in the 70s (930 logic gates) and it's
         | capable of driving a VGA monitor and 4-bit sound while running
         | at 6.25Mhz. In my opinion, it is beautifully simple and
         | elegant.
         | 
         | [0] https://gigatron.io
        
       | Milner08 wrote:
       | Tom Scott has done videos where this has been either used
       | directly as part of the video or has been in the background.
       | 
       | For example - https://www.youtube.com/watch?v=Z5JC9Ve1sfI - It
       | certainly makes for a cool background.
        
       | ozarkerD wrote:
       | This is AWESOME
        
         | LolWolf wrote:
         | It is very, very cool :)
        
       | cushychicken wrote:
       | Wait - this thing runs _Windows?!_ I figured it ran some kind of
       | bytecode or toy OS. That 's very neat that it runs a commercial
       | operating system.
       | 
       | I'd seen this post before but I'd never noticed the monitor with
       | the Windows login screen.
        
         | the-dude wrote:
         | I doubt it. There seem to be several SBCs in the picture with
         | the Windows terminal.
         | 
         | The Windows terminal is probably used to communicate with the
         | megaprocessor.
        
         | Liquid_Fire wrote:
         | It definitely does not run Windows. It has 32 kB of RAM, 16-bit
         | registers and a custom instruction set. That will never run
         | Windows 1, let alone Windows 7 :)
        
           | sundvor wrote:
           | That's still more memory than my old Vic20 had. :)
        
         | orbital-decay wrote:
         | Hah, of course not. The PC acts as a terminal/controller for
         | this machine. Running Windows 7 on a 8 KHz CPU is impossible,
         | even on a x86-compatible one. WinXP has been shown to run on an
         | extremely underclocked 8 MHz Pentium CPU, booting in half an
         | hour: https://winhistory.de/more/386/xpmini_en.htm
        
           | garaetjjte wrote:
           | If you have enough RAM and patience, you can emulate anything
           | even on small CPU. eg. https://dmitry.gr/?r=05.Projects&proj=
           | 07.%20Linux%20on%208bi...
        
             | colonwqbang wrote:
             | It has only 256 bytes of RAM
        
             | adrianN wrote:
             | 30,000 minutes are more than 20 days. That's a lot of
             | patience to boot Windows.
        
       | diordiderot wrote:
       | This is currently sitting in the computing history museum in
       | Cambridge. 10 pounds entry. They have loads of old computers and
       | consoles
        
         | jazzyjackson wrote:
         | Massachusetts or UK?
        
           | sbierwagen wrote:
           | Would a museum in the United States have an admission fee
           | denominated in pounds?
        
             | billsmithaustin wrote:
             | No. It's a computing museum so the admission fee would be
             | denominated in "pound coin".
        
           | LaputanMachine wrote:
           | UK. Here's the Megaprocessor on the museum's website:
           | https://www.computinghistory.org.uk/det/43063/The-
           | Megaproces...
        
           | [deleted]
        
       | ryanmercer wrote:
       | That is fantastically impressive and reminds me of something Sam
       | Altman said once
       | 
       | "Alan Kay gave me an Alto. That's not the very last computer that
       | I think is within my capability to understand everything that's
       | happening in there, but it's getting near the end."
       | https://mastersofscale.com/sam-altman-why-customer-love-is-a...
       | 
       | This is a visual representation of about what I understand about
       | a processor and still outside of what I could actually make
       | without a lot of reference material.
        
       | alberto_ol wrote:
       | Previous submission, 88 comments
       | 
       | https://news.ycombinator.com/item?id=12317217
        
       | dTal wrote:
       | Missed opportunity to call it a "macroprocessor".
        
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       (page generated 2021-11-18 23:01 UTC)