Collapse OS

I don&#x27;t think just developing a Z80 operating system is enough. The whole ecosystem needs to be preserved.<p>In agriculture, we have the doomsday seed vault [0] just for this purpose. If we anticipate collapse of the current economic system or society, I think we should build a doomsday computer vault, that keeps everything we need to rebuild the computing industry in a underground bunker. It keeps everything we need in a controlled environment, such as 8080, Z80, m68k, motherboards, logic chips, I&#x2F;O controllers, ROM&#x2F;RAM, generic electronic parts, soldering irons, oscilloscopes, logic analyzers, schematics, documentation, textbooks, software. We also keep some complete, standalone computer systems such as desktops and laptops, and all the parts that need to service them. We also need to preserve the old semiconductor production lines around the world, although probably not in the same bunker. Even if we fail to build better systems, 8080s are already useful enough!<p>Meanwhile in peace time, we need to form a team of experts that makes a roadmap to rebootstrap the computing technology for the future using parts from the bunker, with a step-by-step plan, that can be easily followed and executed.<p>[0] <a href="https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Svalbard_Global_Seed_Vault" rel="nofollow">https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Svalbard_Global_Seed_Vault</a>

I&#x27;ve been sort of half-assed working on a novel about a post-tech future (100+ years after apocalypse), where a handful of people retained some technology by virtue of having stored information about it in a manner that survived and a tradition of scavenging and trading and a sort of religion based on maintaining it in a working state. So, this is a fun read and thought experiment, even if an 8-bit computer is probably not my highest priority when thinking of &quot;when the shit hits the fan, as seems more likely today than it did five years ago, what do I want to have in my survival kit?&quot;<p>One of the questions I keep coming back to for such a scenario, and still haven&#x27;t come up with a great answer for, is how does someone living in a world without the ability to manufacture a computer still have computers that work 100+ years after the last one was made? Even manufacturing transistors without modern methods is non-trivial. Will a Z80 last 100+ years? I mean, maybe, if it&#x27;s kept dry and not exposed to anything corrosive. I&#x27;ve got a Commodore 64 that&#x27;s ~40 years old and still works...so, 100 years seems reachable, but there have to be extenuating circumstances to get to that &quot;post-tech&quot; world (though I guess in a post apocalyptic world, the value of computers would be seen as minimal for a few years while survival is the only concern, so just forgetting could be enough).

I think some sort or retro low-performance OS should start with NeXTSTEP.<p>Ryzen processors have 80MB of L3 cache! IIRC that may have been twice what was needed to run the colorized versions of NeXT.<p>A lot of &quot;man the old days were all we needed&quot; recollections of Windows and DOS forget how crappy those OSes were...<p>But NeXT? That was basically a modern OS, with a bit less anti-aliasing. XWindow systems STILL look horrible compared to it.<p>It fits in L3 cache. 5-10 NEXT hard disks fit in RAM!<p>It had a web 1.0 browser, TCPIP networking, all the productivity apps. It had DOOM.<p>Sure Mach the microkernel was buggy and leaked memory, but kernels... there&#x27;s lots of kernels now.<p>I think it would be a great project to start with the NextOS and carefully rebuild it up with good security and multitasking.<p>It would be fun to run NeXTSTEP on bare metal with RAMdisks (spare a processor to do the writes to SSD), and compare with other systems, see if it feels ludicrously fast or not.

A neat idea!<p>I think we could also get started now. Not necessarily de-escalating tech, but realizing that the fundamental supply of newer, more powerful chips might not last even with a shift to more plentiful supplies of rare-earth metals due to our need to get off of fossil fuels, fast. I think it might be useful in the more immediate term to be able to lock-in the minimum set of features that make the web and Internet useful then distribute that as widely as possible on low-power, commodity platforms with resilient networks that <i>could</i> survive super-storms knocking out huge swaths of devices in one fell swoop.<p>Low-power p2p protocols, mesh networking, recycling devices, component-platforms that allow scavenging and make-shift repairs, etc.<p>Until we can solve the green energy problem it might be nice to know that even if your community gets hit with a storm or flood, it&#x27;s still possible to restore and maintain network services rapidly in the aftermath. Simply being able to send a message to someone would be a big deal.

I was pontificating about my 401k fund and what I should do if I find it no longer exists when I need to start using it.<p>The older gentleman who was polite enough to listen to me said, &quot;It&#x27;s ok guy, if that 401k doesn&#x27;t exist, then neither will you&quot;.<p>And so I think I will not stockpile any computers for later. I do like the engineering spirit of this however.

So, let me see if I understand this correctly: this is supposed to run on z80-based computers after an armageddon comes and all the other &quot;modern&quot; computers are out of business, so people start building them by scavenging parts. Ok.<p>So, first of all, how are you supposed to download this thing onto your homebrew computer, given that internet will most likely be down?<p>&quot;But if the collapse magnitude is right, then this project will change the course of our history, which makes it worth trying.&quot;<p>Mmmh, I think the author is a bit on the hyperbolic side here. I&#x27;m quite sure that anyone that can design &amp; assemble a z80 computer can quite comfortably code some basic utilities by himself just fine. All the others won&#x27;t care a bit about your OS. Sorry if I sounded harsh, but I actually was.

For anyone interested in the idea of keeping old computers running, I highly highly recommend the Living Computer Museum in Seattle [0]. It was started by Paul Allen and has some of the coolest stuff I&#x27;ve ever seen. Their goal is to restore old computers to working condition and have them look&#x2F;feel&#x2F;smell&#x2F;work the same as they did when new. I got to see a ton of old computers that I had as a kid. I even got to write a program in BASIC on the original IBM PC like I did when I was a kid! [1]<p>[0] <a href="https:&#x2F;&#x2F;www.livingcomputers.org" rel="nofollow">https:&#x2F;&#x2F;www.livingcomputers.org</a><p>[1] <a href="https:&#x2F;&#x2F;twitter.com&#x2F;TeriRadichel&#x2F;status&#x2F;1164369796307116033" rel="nofollow">https:&#x2F;&#x2F;twitter.com&#x2F;TeriRadichel&#x2F;status&#x2F;1164369796307116033</a>

Why can it be only useful after a collapse?<p>If it can be useful, than it can also be useful today to all the (poor) tinker people around the world today. There are lots of alternative eco villages etc. trying to be self sufficient, who do all kinds of recycling and improvised technology. If this adopts with those people, then it might be useful.<p>But if they cannot use this today, then I don&#x27;t see how a broken down surviver group could use it.

Forth is the ideal language for bootstrapping a cobbled-together computer from whatever scraps you can find. Forth gives you a shell, an assembler, a disassembler, and a rich, extensible programming language in a few kilobytes. You can peek or poke hardware interactively, or use the REPL as a calculator. Forth-style assemblers also make cross-compilation very practical.<p>If I was tasked with bootstrapping a post-apocalyptic computer from junk, a hard copy of a well-commented Forth implementation would be a welcome assistance.

I like the Collapse OS concept. I once typed Fig Forth from a booklet I ordered from America into a Sharp Z80 computer. Society was in the main computer free at the time. It was like the post collapse era. To restart the software industry from scratch; I recommend etching a modern version of that Fig Forth booklet onto stone tablets; perhaps provide a scheme interpreter written in forth as well. They will never need anything else.

I like the concept, but I&#x27;m not sure that the Z-80 is the best implementation substrate -- it&#x27;s got a lot of oddball properties and special case instruction encodings (due in part to the way things were squeezed in around the base 8080 instruction set).<p>A PDP-8 can be implemented in fewer transistors (original DEC wiring diagrams are on bitsavers, and github has source for several clones in Verilog), and DEC already shipped a moderately full software suite for it.

Why does the author think the global supply chain will collapse in the next ten years? What scenario do they envision?<p>Climate change? Will cost trillions of dollars and billions of lives, but will likely be played out over course of several decades. We will be stressing out about it but its not going to be electronics-ending apocalyptic<p>Nuclear war? Please. The countries that have the capability are also level-headed enough to use them to play brinksmanship, despite what the news is telling us. These countries want deterrence, not to blow stuff up.<p>Disease? We&#x27;re too widely distributed and the most successful viruses are ones that infect but do not kill. Ebola is scary but its too destructive for its own good which makes it easy to contain. The most successful virus is the common cold, and possibly HIV which is certainly a serious problem, but nobody&#x27;s out there building shelters because of that.<p>Water&#x2F;food supply? Fresh water is a function of energy, and if anything is a plus about climate change its that we&#x27;re gonna have a lot of fresh water raining down on us from the Earth trying to compensate for higher temps.<p>Second order effects from climate change will likely affect arable land and is worrisome but it may also open up new areas for growth and will likely play out over time, so I&#x27;m considering this more of a political problem.<p>The only things I can think of are either:<p>1) A sudden disappearance of rare earth metals needed to make electronic, which would be massively inconvenient but we&#x27;d figure out a way around that, either by it suddenly becoming more valuable to recycle old electronics or not needing them in the first place. Besides if this happens we&#x27;d just get extra motivated to start mining asteroids.<p>2) Celestial events like asteroid strike or Coronal Mass ejection hitting Earth in the wrong way. The first problem is mitigated with asteroid tracking and we&#x27;re getting better at that, and the second one would make for an interesting 6 months but pretty sure we&#x27;d get back on track pretty quick.<p>I am all for technology that does not depend on a complex global supply chain - we will need to manufacture simple but sophisticated tech in space and mars in the future but this prepper BS is just fantasy driven by a hyper-apocalyptic news cycle shlepping around clickbait.<p>What am I not worried about that I should be? What massively apocalyptic event is going to happen in 10 years to turn us back to the middle ages? Seriously.

In the event of a sufficiently large collapse, people will be so far down on Maslow&#x27;s hierarchy of needs that an OS will be about the last thing on their minds.

Give me a good slide rule and a manual of practical mathematics, eh?<p>As for scavenged parts, you&#x27;re going to need a warehouse of manuals and datasheets, eh?<p>Depending on the details of your post-apocalyptic scenario planning, simple automation driven by relays or clockwork logic will be more likely than e.g. scavenged microcontrollers.<p>I applaud the spirit of the project though: I don&#x27;t want to live on Gilligan&#x27;s Island making everything out of coconuts and vines.

Reminds me of Global Village Construction Set<p><a href="https:&#x2F;&#x2F;www.opensourceecology.org&#x2F;gvcs&#x2F;" rel="nofollow">https:&#x2F;&#x2F;www.opensourceecology.org&#x2F;gvcs&#x2F;</a><p><i>The Global Village Construction Set (GVCS) is a modular, DIY, low-cost, high-performance platform that allows for the easy fabrication of the 50 different Industrial Machines that it takes to build a small, sustainable civilization</i>

Long Tien Nguyen and Alan Kay&#x27;s Cuneiform Tablets seem relevant: <a href="https:&#x2F;&#x2F;archive.org&#x2F;details&#x2F;tr2015004_cuneiform" rel="nofollow">https:&#x2F;&#x2F;archive.org&#x2F;details&#x2F;tr2015004_cuneiform</a>

<i>But if someone has a hint about useful prior art, please let me know.</i><p><a href="http:&#x2F;&#x2F;fuzix.org&#x2F;" rel="nofollow">http:&#x2F;&#x2F;fuzix.org&#x2F;</a> - lots of 8-bit targets, z80 included<p><a href="http:&#x2F;&#x2F;cowlark.com&#x2F;cpmish&#x2F;index.html" rel="nofollow">http:&#x2F;&#x2F;cowlark.com&#x2F;cpmish&#x2F;index.html</a> - has a vi-like editor, assembler, and is cp&#x2F;m compatible so it can run lots of old cp&#x2F;m software like various compilers

I think a useful adjunct to this sort of project would be a project that describes a really useful general-purpose CPU that can actually run a lot of advanced software but that&#x27;s still as simple as possible --- and work out a realistic path for bootstrapping its manufacturing. A stripped down 32-bit RISCV for example only needs tens of thousands of gates but could run most modern software.<p>In conjunction with that, it would be good to have an archive of useful software and data in a durable format where access to that data can also be bootstrapped. I&#x27;m not sure what that format would be...

If I were to pick an 8-bit processor for a post-apocalyptic future, it&#x27;d be the single chip version of the Fairchild F8, not a Z80.<p>It was designed to be extremely simple and reduced in scope to the minimum of what a processor needed. It went into space. Radiation hardened versions were made.<p>The original version had its functionality broken up into multiple chips. That could allow for easier repairs.<p>I don&#x27;t know how many transistors were in it, but I doubt it&#x27;s more than the Z80 or 6502.<p>The RCA 1802 is another one I&#x27;d consider. In fact, it will likely outlive the human race entirely, as it&#x27;s in the Voyager spacecrafts.

Relevant to this goal is Stage0 [0], which is attempt to bootstrap a compiler toolchain. It is still a work in progress but the most promising attempt I have seen.<p>[0] <a href="https:&#x2F;&#x2F;github.com&#x2F;oriansj&#x2F;stage0" rel="nofollow">https:&#x2F;&#x2F;github.com&#x2F;oriansj&#x2F;stage0</a>

I love projects like these. One that has me fascinated is the idea of building a computer than can last centuries. Can it be done?<p>- Will the ICs last that long, can they?<p>- How will it get electricity if the sockets and voltage standards change?<p>- How do you make it durable to dropping, water, dust, etc?<p>- What sort of writable storage can last that long without degrading?<p>- How do you edit fonts as language changes over time?<p>- What sort of libraries and documentation do you include?<p>- Should you include some sort of Rosetta Stone for new users?

Neat idea, but I&#x27;m not seeing the window of usefulness for this.<p>If society collapses and recovers relatively quickly, we likely can coast for 10-20 years on the computers that have already been built. This would be what I&#x27;d expect to happen with a point-in-time catastrophe that disrupts everything but then ends and we can all set to work to rebuilding everything. (Like a massive economic collapse, huge meteor strike, nuclear winter, etc.) Even if 95% of computers become inoperable, there&#x27;s a lot you can do with the remaining 5%. Probably more than what you can do with new stuff you build.<p>Another scenario is that we recover really slowly. This would be due to some kind of enduring factor that holds back humanity, like a really long-term famine or global political instability that we somehow cannot reset. In that case, what&#x27;s the hurry to develop software that&#x27;s ready to go? Maximizing compute capability doesn&#x27;t seem like it would be the thing that tips the scales and allows society to get rolling again. For that you need to solve whatever the root problem is.<p>TLDR, if we fall, maybe there is nothing holding us down, and we can bounce back up relatively quickly, in which case we don&#x27;t need this. Or there is something holding us down, then it seems unlikely that computing is what we need to solve that.<p>Maybe there are other scenarios that I haven&#x27;t thought of, though. Or ways that computing would help in the above scenarios.

The digital version of prep-er style hoarding for the not-far-off-inevitable apocalypse.<p>Love the idea to make it run on simple 8-bit CPUs that will be scavenged Fallout-style, but seems to presume that no &#x27;newer&#x27; technology would survive and be functional.<p>Wonderful to see, none the less.

Anyone wondering why the Z80 chip, just read the FAQ:<p><a href="https:&#x2F;&#x2F;collapseos.org&#x2F;why.html" rel="nofollow">https:&#x2F;&#x2F;collapseos.org&#x2F;why.html</a><p>&quot;The z80 has 9000 transistors. 9000! Compared to the millions we have in any modern CPU, that&#x27;s nothing!&quot;

Why z80 and not x86 or AArch, which are both more readily accessible today? This whole idea reeks of someone trying to reconcile their love of old computers with their poorly considered death-cult Malthusianism.

One way to gain traction (pre-collapse) might be to hold competitions about getting it to run on challenging &quot;salvaged&quot; systems and demonstrating impressive ways to copy it from one system to another.

A bit of a tangent but in the novel &quot;The Windup Girl&quot; they live in a post oil world which essentially ended up more of a total societal restructuring that pretty much resembled what we&#x27;d consider a collapse. Nations fell and in some places companies took over. Cities collapsed as the population shrank and technology shifted to focus more on bio engineering to make up for the loss of all the mechanical&#x2F;electrical technology that ran our world since powering it all got a lot more expensive after the oil was gone.<p>In one part a high security government installation was described with &quot;ancient&quot; PC&#x27;s. They couldn&#x27;t make new ones so they kept whatever they could running and the narrators mind was blown thinking about how much energy they wasted.<p>I think one of the top priorities for a project like this should be making it easy to implement considering practically everything you would use now days to get help getting it working won&#x27;t exist. No websites or forums or anything like that.

I&#x27;ve wondered about this a few times and always started by asking myself what would be left after armageddon.<p>Android phones. Tens of millions of them. It <i>must</i> be the most ubiquitous computing platform by now...

I had been thinking about similar projects myself. I figure that experience with the z80, 68000, and the 6502 would give someone a platform for hacking for at least the next century. There are some dozens of 68000-like chips in a single car. I&#x2F;O is as simple as LEDs and toggle switches for the bare necessities, such as bootstrapping other I&#x2F;O options. Worked for the Altair 8800. From there one could implement morse-like momentary switch input. In these (possibly far-fetched) scenarios, going back to things like ticker tape and printers would make a decent amount of sense. Perhaps spools of wire could be used as &quot;tape&quot; for programs and data, as wire recorders existed before plastic tapes were available. I love seeing how home fabrication is developing, with people making simple silicon in their garage, but there is value to a basic tool chain that doesn&#x27;t require as much sophistication and supply chains. I truly hope we don&#x27;t live to see such a world, as the suffering would be immense. That said, I have no idea how complex supply chains can be expected to persist without fossil fuels.

This is a fun idea.<p>I often think about hoarding a collection of software and media for an end of the world scenario. Then another year goes by and the world is still here.

Why not a Rad Hard 8086 <a href="https:&#x2F;&#x2F;www.renesas.com&#x2F;in&#x2F;en&#x2F;products&#x2F;space-harsh-environment&#x2F;rad-hard-digital&#x2F;rh-microprocessors-peripherals&#x2F;device&#x2F;HS-80C86RH.html" rel="nofollow">https:&#x2F;&#x2F;www.renesas.com&#x2F;in&#x2F;en&#x2F;products&#x2F;space-harsh-environme...</a> or maybe a Rad Hard RCA CPD1802 <a href="https:&#x2F;&#x2F;www.renesas.com&#x2F;in&#x2F;en&#x2F;products&#x2F;space-harsh-environment&#x2F;harsh-environment&#x2F;microprocessors-peripherals&#x2F;device&#x2F;CDP1802A.html" rel="nofollow">https:&#x2F;&#x2F;www.renesas.com&#x2F;in&#x2F;en&#x2F;products&#x2F;space-harsh-environme...</a> ? Those might survive a hydrogen bomb if not too close.<p>I&#x27;ve thought about this a little, and I think rebooting vacuum tube technology from scratch is possible more easily. Not trivial, but possible. Once you get reliable triodes, you&#x27;re on your way.

They have <i>much</i> too rosy an idea of the future. Nuclear war is actually the only thing that will <i>save</i> them! By that time countries will be their own separate cyber-Fascist states, actually cooperating with each other to keep their citizens, by that time implanted with chips in their brains and connected to the central Net, in line. Oh, by the way, they won&#x27;t be forced to have the chips implanted, they&#x27;ll willingly line up for it! So they can get their Dominos Pizza, and Amazon deliveries, and Google Map directions all with a thought! Or so they&#x27;ll be told. Besides, the asymmetry in computing power between the rulers and the enslaved will be laughable. The government will have even (more) powerful quantum based machines. Cobbled together 48K Z80 machines will be insignificant. If they&#x27;re even tolerated. Which they won&#x27;t be...

Everyone is comparing it with Seed Valut[0]. its better to have a complete eco-system for computers. But its a nice forward step to save the technology in small computer, which gives the basic idea of how to proceed further. in case if you start storing the everything you need lots of space underground which seems not feasible.<p>In my opinion, there should be system in which all the blueprints for the technology is saved &amp; that machine should be self sufficient to run on its own power, memory and should be capable enough to educate or atleast gives the basic idea of structure, as after the post Collapse, if anyone who is lucky enough get this technology, can improve and build a new system.<p>I like the idea of Collapse OS, in similar manner create the machine which can run any software&#x2F;os or supports most basic and used operations.<p>Same goes with the books as well.<p>~Nauman

Why Z80? Is it like the 2nd most common processor type or something? Where would one find a Z80 when scavenging?

Do you know that can be possible (more than what you can think) the situation you told, Mr Virgil Dupras, in 2022? You were thinking about informatic and not about events on the planet. For that time (2022) all the wolrd should have a negative situation where a solar storm arrives on the planet and destroys many electrical&#x2F;electronics... It is called Carrington event and happens every 150 years... Please ask to the NASA as they know well. US Government started researches about to stop, already in 2004...

Is there a rad-hardened version of z80?

The manifesto&#x2F;winter-is-coming bits and overall design reads to me like TempleOS without the mental illness. Eg, a shell that &quot;compiles&quot;, no protected memory, etc.

Seems strange to go for something like Z80 from the 8-Bit home computer age, when the goal is simple manufacturing. Should go with the PDP-11 line instead which had a long history spanning different technologies, going across large and simple to manufacture to more integrated and miniaturized, faster, with more memory, with a standardized set of peripherals and instruction set architecture.

I&#x27;ll chose TempleOS for my go-to &quot;paranoid schizophrenic philosophy&quot; daily driver over CollapseOS anyday, and I&#x27;m atheist.

To me a much more interesting avenue to be able to “bootstrap the pc era” would be to achieve DIY knowledge enough to recreate TTL on a garage. Afterwards you can at least create a computer from the 80s, as Ben Eater is doing in his youtube channel.

<a href="https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Apocalyptic_and_post-apocalyptic_fiction#Failure_of_modern_technology" rel="nofollow">https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Apocalyptic_and_post-apocalypt...</a>

Eh, our current ecosystem is such a mess I wouldn&#x27;t miss it. I worked on cross stuff for Nixpkgs in part due to a more optimistic take: Let&#x27;s bootstrap all the good stuff <i>en masse</i> onto freer hardware.

This project is really out of left field, especially as someone who doesn&#x27;t tend to wear tinfoil hats. I wouldn&#x27;t mind if it was marketed more as some kind of lightweight OS though.

Maybe a system based on ARM or MIPS @ 1GHz very common in a modem-router. Z80 @ 8Mhz cannot dispay even a 640x480 image. it would be wonderful recycling modems as stand-alone computers

Reminds me of the anime series: <a href="https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Dr._Stone" rel="nofollow">https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Dr._Stone</a>

Reminds me of: <a href="https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Dr._Stone" rel="nofollow">https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Dr._Stone</a>

What if computers caused the collapse though? Doesn&#x27;t this risk reseeding the problem? Maybe it&#x27;d be better in the long run if we have to reinvent.

In the Herbert Dune, civilization collapsed because of smart machines. So after renaissance they are completely banned for the future use.

Could this run on TI calculators? They use Z80 but I don&#x27;t see them mentionied. Looks like a cool project!

Lets think about what technologies are most likely to be around after an apocalyptic event... Probably something that everyone has, that there are millions of.. something with a screen and a keyboard... very light and easy to transport.... maybe even something with a battery, and signals processing chips.... na screw it, lets just use a desktop. :P

A fascinating thought experiment.<p>As the author points out, probably useless, but still fascinating.

I&#x27;m interested in the reasons the author sees for the ~2030 collapse.

Should come with a bicycle to generate power

Related to the post, I highly recommend reading &quot;The Knowledge: How to Rebuild Our World from Scratch&quot; [1] if you are interested in foundational technology that underpins our civilization. This type of information is often forgotten or taken for granted in our highly dependent late-capitalism society.<p>[1] <a href="https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;The_Knowledge:_How_to_Rebuild_Our_World_from_Scratch" rel="nofollow">https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;The_Knowledge:_How_to_Rebuild_...</a>

Does this work for the T80 FPGA core?

This collapse thing. It&#x27;s real?

IMHO - the Z80 is probably not the optimum starting point. Its close cousin, the 8080 started out as a TTL cpu built into early Datapoint terminals. Intel took the Datapoint logic design and ISA and integrated it into LSI silicon. Anything a Z80 can do, an 8080 can do - albeit less efficiently.<p>With an 8080 equivalent running a serial character display terminal based on an oscilloscope CRT (1940s RADAR tech) you have an input&#x2F;output device.<p>This leaves the main job of processing to another cpu, which could be 16-bit for arithmetic speed and efficiency. The late 70s, early 80s 8-bit machines were only underpowered because they were doing all of the video output using the same cpu. Separate computation from video generation and you get a much faster system.<p>8-bit cpus rarely needed an OS. They were really only capable of running single applications at a time. All an operating system does is separate hostile C code applications from each other. C is probably not the best starting point to reboot society using 8-bit systems.<p>Forth, or some derivative might be better. Charles Moore&#x27;s original 1968 listings for Forth on an IBM 1130 are available from here: <a href="https:&#x2F;&#x2F;github.com&#x2F;ForthHub&#x2F;discussion&#x2F;issues&#x2F;63" rel="nofollow">https:&#x2F;&#x2F;github.com&#x2F;ForthHub&#x2F;discussion&#x2F;issues&#x2F;63</a><p>Remember also that every mid-1970s microprocessor generally relied on a minicomputer (built from TTL) for its software and logic design. If you go back 10 years (1965) to the PDP-8 minicomputer, these were built from diode-transistor logic or DTL - made from discrete diodes, transistors, resistors and capacitors. This sort of technology could possibly be re-booted more easily for post-apocalypse society.<p>The original 12 bit PDP-8 contained 10,148 diodes, 1409 transistors, 5615 resistors, and 1674 capacitors. See- <a href="https:&#x2F;&#x2F;www.pdp8.net&#x2F;straight8&#x2F;functional_restore.shtml" rel="nofollow">https:&#x2F;&#x2F;www.pdp8.net&#x2F;straight8&#x2F;functional_restore.shtml</a><p>Scale these figures by 1.33 and you have the approximate requirements for a 16-bit architecture.<p>Whilst over 50 years old, the PDP-8 could run BASIC at speeds not too dissimilar to the early 8-bit micros that appeared in 1976 - about 10 years later.<p>It used a modular construction - and if you did find yourself with an excess of diodes and transistors, the best approach might be to build a series of logic modules - loosely based on the 7400 series, but using DTL for simplicity. If you were to standardise on a footprint similar to a 40 pin DIP, you could probably recreate about 8 NAND gates in such a device.<p>Some years ago I looked at the NAND to Tetris cpu, and worked out a bitslice design based entirely on 2-input NANDs. Each bitslice needed 80 NANDs, so a 16-bit machine would need 1280 gates. Memory would be difficult, but something could be implemented using shift registers. You could of course revert back to storing charge on a CRT screen - which formed the basis of the 1K words of memory on the Manchester Baby machine of 1949 (Williams Tube).<p>Finally - never underestimate audio frequency generation, and storing signals as audio tones - something that cpus are good at. Possibly use a rotating magnetic drum for storage.<p>In the summer of 1984 - a friend and I, who both owned Sinclair ZX81s set up a 1-way data link between one machine and the other across our college dorms - using a FM transmitter bug and an FM radio receiver - over a distance of 300 feet.

Like other in this thread I have been thinking about this problem on and off for a while. I think that many of the comments stating that the Z80 is probably not the best choice are right (I know nothing about the Z80) and would like to extend some of their thinking.<p>The primary design requirement for a stand alone computer system in a post-* world is simplicity, maintainability, and debugability. It must be possible for a single user to do _everything_ in situ. There are very few existing systems that meet all three of these criteria across the whole hardward-firmware-software stack, and modern technology companies are actively moving away from this.<p>At all levels this requires extensive and open documentation and implementations, and ideally a real standard.<p>The hardware level would probably need a complete rethink, and if you want good peripheral support (e.g. to be able to try to access whatever data device you come across) then you need a solution that doesn&#x27;t require a subsystem kernel maintainer for everything, or you just give up on that. A potential 4th requirement here could be a large supply of parts since in most scenarios it is extremely unlikely that anyone will be able to get a fab working again for hundreds or thousands of years. Maybe radiation hardened large feature size ICs or something like that. The alternative would be a zillion RPis (with some alternate data storage interface) so that hopefully some of them survive and continue to work after 100s of years, but this seems like a much riskier bet than trying to actually engineer something to survive for a very long time. Above the IC level the ability for someone to replace parts without special tooling beyond maybe a soldering iron also seems like it is probably also important.<p>At the software level there are two existing systems that might serve, one of the Smalltalks, or one of the lisps (my bias says common lisp, despite the warts). Assembly and C are just not a big enough lever for a single individual, and other things like Java seem to have been intentionally engineered to deprive individual users of power. The objective here is not to be fast, the objective is to retain access to computation at all so that the knowledge of how to work with such systems is not lost. Also at the software level the requirements pretty much preclude things like browsers that are so monstrously complex that there no hope than an individual could ever hope to maintain a legacy artifact (or probably even compile one of the monsters) for interpreting modern web documents.<p>I do not think that we can expect the current incentive structure around software and hardware to accidentally create something that can meet these requirements. If anything it is going in the other direction as large corporations can employ technology that can _only_ be maintained by large engineering teams. We are putting little computers in everything, but they are useless to anyone in a world without a network.

Are Z80 systems and alike very common? Seems like a niche hobby.<p>I&#x27;m thinking old phones, tablets, and portable computers will be more common. I keep several bootable USB drives which have lots of ebooks, audio books, videos, software, and games along with several old laptops&#x2F;netbooks which were free. I also keep some of those files on microSD cards to make them accessible with tablets.<p>IMO collapse will be very boring so lots of books, audio files, video games, and music would be nice to have if it can be run off small off grid solar setups.

I really like this idea!<p>Makes me wonder what possibilities become, er, possible if we up the computing power a few orders of magnitude to a Pi Zero W or Pi 4.<p>From what I understand it’s fairly easy to use a Pi as an LTE Router for longer ranges and WiFi for shorter ranges. I wonder if the right microsd cards and were stockpiled one would be able to reconnect several communities in a mesh.

Ok, but what user programs will we really need then for it? Other than re-building technology. Isn&#x27;t &quot;too much technology&quot; basically the single biggest root issue of current state of humankind, and planet in general?