Linux on C64, 8086, & Intel 4004

With a little work, Linux can boot on 8 and 4 bit CPUs from the 1970s. Slowly.
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[@niclash]

Next; Linux on the Apollo flight computer ;-)

[@edwinov]

Maybe this time we can actually make it to the moon!

[@Nexus9_KD6-4.8]

Simply incredible. Little to no actual practical use but I absolutely love stuff like this.

[@unpotatoedsalmon]

Lubduke I have a rather large pile of shame I need to paint you have given me something else to distract myself thank you

[@FPT2030]

8 bits ?? 4+4 . 4x5 4 bits for a table selecting each 16 tables having 5 bits long address data 4+5 = 9 bits ==400+++ asci ichars . this can be used for memory too. 4+5+7 is 16 bits but in 3 stages

[@Ensue85A]

i8085A?

[@johnrickard8512]

What gets me is that this CPU is literally a calculator... And not of the graphing variety

[@johnrickard8512]

Alan Turing would be proud

[@FrDismasSayreOP]

Looking forward to the VIC20 and ZX 80 Spectrum versions

[@maidpretty]

No need for. Vic20 runs on MOS 6502, you can check out GeckOS and couple of other unix-like OS for 6502. As for Z80 - it's binary compatible with Intel 8080 being an improved variant of it. So Intel 4004 is as far you can go.

[@nezbrun872]

Needs to get meta: emulate an i4004 on Linux running on MIPS emulated by an i4004. I breadboarded an i4004 a few years ago, I was so proud when I got it to blink an LED, and considered the project complete. What low expectations and goals I have!

[@myne00]

Well, now you have the base to build your Quake RTX port that renders 1 frame per month

[@gcolombelli]

Anyone got a DECstation 2100 to run the 4004 emulator running the MIPS emulator on it?

[@RKelleyCook]

Its MP944 time (the world's first microprocessor) which was part of the original Central Air Data Computer in the Grumman F-14. Its an amazing 20bit floating point computer designed by Ray Holt who at the time wasn't old enough to know that what he designed was impossible. He beat the much less capable Intel 4004 by about a year. Unfortunately all of them seemed to have been destroyed by the dolts in the Dept of Defense.

[@wernerviehhauser94]

Maybe Iran still has a few in their old Tomcats

[@JanuszKrysztofiak]

Some years ago I saw a similar project, but with an 8-bit AVR MCU. It emulated some 'normal' CPU and accessed RAM chips via GPIO to provide an environment for Linux. Obviously, it took days to get to login prompt.

[@dmitrygr]

That was my project too. I did the original Linux on avr in 2012. And that record stood till 2023. Someone beat it (on a Mos6510). I did the 4004 to take my record back

[@JanuszKrysztofiak]

@@dmitrygr Respect :)

[@krunkle5136]

This is beyond cursed. Imagine the constant swapping.

[@von_nobody]

Now goal would be "ho make fastest Linux book" on 4004 :D

[@brianchandler3346]

Miss my old restored 8088XT with a double spindle drive. Brought back a good memory. Salvaged it from multiple junk machines when I was a teen and actually got DOS 6.22 running on it. 😂🤘🤓

[@abram7547]

Finally some positive news, feels so good after all the doom n gloom you've been reporting lately

[@justinhall3243]

The 4004 cannot address more than 4kb of RAM! HOW???

[@metaforest]

when you emulate a larger processor you abstract away things like bank switching. at any moment the 4004 is only addressing a very small window of data and instructions.

[@treelineresearch3387]

The approach in this case is absolutely bonkers (emulate MIPS on 4004, boot linux on the virtual MIPS), but in general expanding memory is pretty much always some kind of bank switching or mapping. 6502 and Z80 could only address 64k but plenty of machines back in the day had more via expanded RAM cards.

[@bomberfish77]

well the 4004 port used some clever bank switching to bump that to 8kb, but that's still super impressive

[@snap_oversteer]

Bankswitching, in the end you can 'run' Linux with only pen and paper and lot of free time.

[@cybernit3]

Running at a clock rate of 740 kHz, the 4004 could address 4KB of read-only memory (ROM) to hold the program and 640 bytes of RAM to store the input and computed results. - PCMag. It is amazing if they can run Linux, but probably uses some clever bank switching for more memory. Also there is some Z80 hacker who did a primitive MMU on it too.

[@5speedfatty]

this takes "reviving old PC's" to its logical end...

[@rogerlundstrom6926]

... Next step.. Getting Linux to run on einiac.. and of course: Getting it to run on an automatic knitting machine.. There is also a "processor" which is based on people moving rocks around in accordance to pre-set patterns ("programs")..

[@5speedfatty]

@@rogerlundstrom6926 ... Linux on Tubes. jesus thats a scary thought...

[@TheSolidSnakeOil]

512k of RAM is asking a lot of an 8086 PC. It's by no means undoable as there are small companies that still pump out that memory. Way back when I (my parents really) had one with 128k and that was a lot at the time.

[@snap_oversteer]

XTs were commonly expanded to full 640k in the later 80s, all XTs I've bought so far had already some kind of memory upgrade or were with motherboards that had full 640k onboard.

[@ka9dgx]

Using an AST Six Pak Premium with the appropriate daughtercards could take an 8088 based XT up to 8 Megabytes of bank swapped RAM

[@Elknkam]

Linux has nothing in it other then prompt commands . That's way it works on ancient hardware.

[@anon_y_mousse]

I want Haiku on my system of Nintendo 8-bit computer.

[@abram7547]

AFAIK, 4004 wasn't really a "4-bit" CPU; rather, it was an 8-bit CPU with a 4-bit data bus

[@amigapelit]

cpu run 4004 is 4 mhz speed

[@-x21-]

​@@amigapelitmore like 0.74mhz

[@vytah]

It had 4-bit registers, 4-bit data bus and treated RAM as a sequence of 4-bit bytes. It had no support for 8 -bit arithmetic at all; to add two bytes, you'd have to use two add instructions. It was as 4-bit as it can be.

[@AUATUWVSH]

@@amigapelit they could implement it on an FPGA and run it many many times faster, but that wouldn't be very retro

[@gcolombelli]

@@AUATUWVSH it would still be cool though, just like the ~25MHz 6809

[@obsoletepowercorrupts]

It could be useful when exotic microarchitectures running an OS (BSD, Linux, etc.) can be an avenue to find bugs. The tendency to see this as a feat is the fact that a low amount of RAM might be used, beyond how Unix would be used via a 512KB mainframe _(so that ROM swap looks to be part fo the trick)._ It terms or speed however, an 8Bit CPU (although some may consider it microcontroller for some instruction-sets) can be faster, as per microcontroller MCU as SoC in say a washing machine, as a stack can be useful. There would, in CPU reduced to an 8But bus whereby a CPU beyond those instead might have a maths-co-processor so redundant registers are used for floating-point to integer conversion to swap a value between a redundant register. If the redundant registers on a 68k chip are not used, it is not necessarily faster than the chip family likened to the C64 _(also a faster version for some)._ The 68020 can run BSD on an A1200 Amiga, and the bus can be clocked down to 16bit from 20, 24 and 32bit. So an 8Bit nix-like system can run but the lower amounts of RAM can incur penalties, whilst a CPU can be made faster even if 8Bit. It is hard to argue a c64 is less like a c128 when it has 128KBytes RAM. Smart-watches with 16KBytes run micropython do remember. A SMART device (washing-machine, or SMART-watch) having a decent amount of RAM _(maybe 64MB or 16MB or 4MB or 2MB or 1MB depending upon limits like an 8Bit bus, unless Amiga-style techniques are used to address a modest amount more)_ could make a nix-style stack (Linux for instance) interacting with micropython and say bluetooth so the python and bluetooth actually become more useful, preventing e-Waste as it could be reprogrammable as there is some RAM as wiggle-room, compared to the 16KByte limits which usually prevent reprogramming by sheer limitation. So an example might be where more than one chip can run in conjunction and one is say 32bit or 64bit, whereas the second chip can changes its bus _(or be emulated or made in hardware-description-language to change its bus)_ between 32bit and say 8bit but largely to say 16bit between 8 and 32bit. A rational would be for massively reductions in floating-point penalties incurred when deliberately only using 16bit floating point. Also then perhaps a phase-locked-loop is used for error correction switching between 16bit and 32bit when micropython can kick-in and be useful, and yet in a 8bit mode, QR-code error correction would suffice having been translated, and maybe a GPIO like IEEE1284 would suffice for some other task. Carrier-signals can be an example of where polynomial and FFT can be handy. With enough RAM _(so, hopefully the approximate megabyte can increase when the bus is unlocked to say 64MB or above)_ the nix-like OS Linux stack, can always be there to make a chip able to ge updates another example of a phase-locked-loop can be for a multiplier-tree, like how people underclock and overclock a CPU. Various battery-saving and bus changes and bit changes _(16Bit FPU and 32Bit and 64Bit and so on)_ and underclocking-overclocking multiplier-tree PLL tricks, all combined, can save performance penalties incurred in coding style, battery usage, and power-saving and heat _(tiny amounts but enough to extend say a capacitor's functionality like a Schmitt trigger)_ or mutliplexor-tristate use-cases. so the use-case of a c64 style CPU is more perhaps a way for concept for these scenarios even if the microarchitecture is different, exotic, custom or changing on the fly or assisted by ASIC. finding bugs, reprogramming and extending life of a gadget otherwise vulnerable to becoming e-Waste could be helped by these things. As for 4Bit, it might be somewhat handy for simple hexadecimal 4 bit conversion. As an aside the blitter is 4bit. Largely though the 8Bit standards of IEEE1284, QR-Codes (and error-correction) ASCII, or some polynomial ranges or adding an alpha-layer such as 8bit to 24bit to make 32bit could be useful for bus changes on the fly or rather that sometimes but with more than one chip so one is 8bit like an MCU but perhaps a CPU instead but next to a 32Bit or 64Bit CPU, working together. Storage interfaces can switch to 8bit from 16Bit like IEEE1284 and IDE-PATA. However, remember than an ISA slot is 8bit and a TPM module has an 8bit interface too and can be used in various ways including a LUKS partition. So small subtle but useful things could already be done with the notion of 8bit but the instruction set is perhaps likely to be different, even if it means using an FPGA where the FFT is already on it rather than only needing to use an FPU chip like a co-processor. A signal path or Chirp might use it, or if LoRaWAN got channel-switching like bluetooth 5.2 ended up with (but different). My comment has no hate in it and I do no harm. I am not appalled or afraid, boasting or envying or complaining... Just saying. Psalms23: Giving thanks and praise to the Lord and peace and love. Also, I'd say Matthew6.

[@cantileveredapotheosis]

Did ELKS ever get x86 processes to handle more than 64kb, I thought they didn't have a good compiler to handle 'far memory' kind of pointers, and a linker that can handler that sort of thing. Effectively you can think of it like running DOS 'tiny' memory model processes

[@roymerkel8008]

think they switched to a fork of GCC (gcc-ia16), which had some LIMITED support for additional segments and memory models, but I never tried it myself outside of parusing their comits, so I don't know what the limits are of the added feature (I DO see commits referencing far pointers and medium model, but I'm not sure if code can be in mulitiple segments or only data)

[@siwiecministro1994]

Doom didn't run well on 386 DX 40MHz. I cannot imagine it running on 8086 or something.

[@helidrones]

What about running Linux on a „Triumph Adler TA 1000“ with it‘s CPU built from discrete TTL logic chips.

[@ka9dgx]

What about a TTL logic CPU booting Linux?

[@gcolombelli]

If you're willing to settle for MINIX instead of Linux, there's one such project already, the Magic-1 by Bill Buzbee.

[@mirror1766]

I learned about 'nibble's when self studying x86 assembly from books over 20 years ago. I presume it didn't completely fade out from there too and is just that assembly programming has faded from being any mainstream thing. As for what would be next, you are probably right about it being nontransistor computers. I can't see it as a practical challenge for tube based computer work so maybe someone would try to make a 'mechanical' replacement for a transistor and boot it there. Kinda feel like emulating another architecture is a cheat in itself though so in my eyes they lost points at that step..

[@myne00]

Honestly, I've always wondered why not 10bits to a byte? Or some other arbitrary number? Why was 4/8, and multiples thereof chosen in the first place? Someone made the decision once upon a time, and best I can tell there's no technical reason for it, and no explanation to be found anywhere.

[@magnum333]

I imagine Minix would be far more useful

[@JohnCrawford1979]

Next level: Linux on a PET. 😉👍

[@MotownBatman]

I Saw this Yesterday I think; My INstant thought was, Linux is 32Bit, This has to be a Late April-Fools LOL

[@bloepje]

I had youtube on autoplay background. I've listened to it for 5 minutes before being able to look at it. I really thought youtube selected an april 1st for me... I always considered ELKS a fluke and mmuless linux was an old project maintained by Samsung a decade ago to get really low end hardware to be smart using a modern os. Never considered that people were really doing this. Even back in 2012 I did not hear of this.

[@MotownBatman]

@@bloepje No Me Neither, I Wish I could do Stuff like this, I'm always bored looking up Oddities on Old Harware. Crazy how long this was under the radar

[@s1nistr433]

This is just your average arch user removing bloat

[@myne00]

😂🤣😂🤣

[@misium]

4004 wasnt meant to be fast ever. It was a calculator chip - S_L_O_W. Those board sized minicomputers of early 70s are much faster than a 4004. Like a pdp-11 (16bit) that unix was written for. In the 60's you had the 12-bit pdp-8. That thing was quite slow, although I dont know how it would compare to a 4004.

[@techrazor3280]

Well, that seems to be rightful place for Linux!! 😁😁

[@tehdudezorz6322]

6502 Please. :p Just watched the video so never mind. Although they did 6510 not the 6502. Also, this takes 256k. that was a LOT of memory back then. "1971 was over a billion years ago" Ouch. Hey man take it easy.

[@hadeseye2297]

Yaaaaaaaay! I still use my Commodore 64. xD How nice to have Unix-like system on it. PS. To be completely honest would be dope to ssh into vm hypervisor or NAS.

[@AndrewRoberts11]

WHY? Using anything less than a 25MHz i486DX or 33MHz ARM3 box, with 8MB of memory, 100MB of HDD space, with a swap partition, was painful in 1995 (by 90s standards), and about the minimum spec necessary for startx not to hang, or for a tcp/ip stack to not constantly swap, to permit you to ftp the latest drivers, which would take an age for a kernel compile.

[@pallharaldsson9015]

You could go further with a microprocessor, there are actually 1-bit CPUs, or usually called microcontrollers. The one I know of from Mororolla has only 256 bytes of RAM.

[@RockBrentwood]

Put it on 8051/8052 and then we'll talk. In fact, do it *straight up* as a RT version of Linux, making full use of the multi-threading hooks in these CPUs. It's got an 8-register window (the base address is in the flags word), a large 128 register space and addressable 1-bit registers, which includes the flags on the flags word. There are also 16 and 32 bit versions in the CPU family.

[@lua-nya]

To spice it up, you could use an RP2040 as an ISA GPU on that 8086 to output DVI and have a faster chip for GPU than for CPU. What I'd like to see is a dual RP2040 or maybe even spicier, esp32-s3 + RP2040 computermade to feel retro.

[@DS-pk4eh]

So maybe C128 with its RAM expansion and 80 chars resolution would be a better candidate instead of C64. Still kudos to all these people. Also, where do you find all that free time to do such a things?

[@catsspat]

I imagine AMD EPYC 4004 series chips are proud of this accomplishment.

[@rogerlundstrom6926]

This reminds me of a thought experiment I usually present to people who thinks consciousness can be equated with processing. (I don't say it's wrong, I just say we don't know and can't know what it is).. and that is: Any program that can be run by any computer can be run by pretty much any computer ever made or theorized.. I don't know if anyone ever made it, but there is a processor which has one single instruction (kind of a mathematical operation and a conditional jump in one).. There is also a theoretical computer which just is a huge field of rocks (a matrix) where humans move those rocks around.. ~if~ we can just build a "powerful enough computer" to actually achieve true self-consciousness in the same way as I do (.. Well.. I don't know if I may be the only person, it's impossible to prove from the outside, but my own self-experience proves to ~me~ that I have it)).. then.. We could also create a huge field of rocks which will experience the same thing.. albeit a lot slower.

[@RoboticsDIY]

This is inspiring, I'm happy to find your channel. Got me thinking how would Linux and Doom run on 8bit guys Comandore X16. And has someone adopted Linux core on 8 bit architecture, not emulating a more modern architecture.

[@edwardcullen1739]

I mean, great and all that... But this is completely and utterly missing the point. I mean, Linus inital motivation was to make something that would take full advantage of the 386... The problem I have with this is that someone, somewhere will believe it's a good idea.

[@DaveMelton]

Has anyone written a Linux kernel for the actual MOS 6510?

[@erintyres3609]

A few years ago I read about an experiment in extreme underclocking. The writer got a Windows PC to run at a clock speed much slower than anyone would normally use, and it was almost 100% busy even when no user programs were started and the mouse and keyboard had not been touched.

[@timrichter1980]

Linux on IBM System/370 anyone? It's operating system MVS 3.8 is free and there is an emulator in various flavours (Hercules).

[@xcoder1122]

ELKS is not Linux. It says it right on the front page in the first sentence: It's a "Linux-like OS". No matter how Linux-like you get, it's not Linux unless it's Linux.

[@TheEVEInspiration]

But it is useful, just not for normal usage. It will show clearly what is essential and what is not and probably discover some bugs along the way. And where there is overhead, lessons that can be applied in other contexts.

[@ernestuz]

I have Linux running 8n my c64, now it's time for WORLD DOMINATION!

[@JamesJones-zt2yx]

That is the true spirit of hacking. (I'd have sworn that "n[iy]bble" never really caught on. I may be wrong...)

[@JohnWilliams-gy5yc]

Can they be set calendar to February 2038? They also fixed the 32-bit time_t?

[@larsulrich2761]

I remember using MINIX on an 8086. It was a miserable experience.

[@bryede]

Meh, get back to me when I can run Linux on the Motorola MC14500B.

[@jaybrooks1098]

the 4004 is only one part of its arch. requires a bunch of extra chips to work. I have always tried to get the full set of 4004 chips but they are hard to obtain.

[@amigapelit]

i member comndore 64 games staring awarege loading 20-30 min loading form 80's

[@FPT2030]

i think you must see a siemens plc who can use step 5 language simatic machine. then you can understand that pc is much more advanced . a plc with step5 use bit datas long . each bit can be only a single button input like 0 or 1 . 1 bit

[@amongussuss341]

i want to run linux by me calculating each individual instruction on a piece of paper

[@patw1687]

I wonder what Linus T. thinks of Linux on a 4-bit machine.

[@Rod_Knee]

I'd love to see a distro that would work on an Amiga 1200.

[@LedoCool1]

Can it run nginx? I want to use it for some lightweight web services.

[@ChrisAthanas]

I watched the demo Nuts

[@jeffyp2483]

would you provide links to the articles in a pinned comment?

[@seylaw]

Maybe some old defense systems might get ported to Linux then?

[@bobclarke5913]

So this makes linux running on something the same age as Linus, yeah?

[@MalalRebooted]

Now get TempleOS on the C64 !

[@iiisaac1312]

And I thought 5 minutes to boot Gentoo on an original Pentium took a long time.

[@replikvltyoutube3727]

is it that riscv emulator that runs basic riscv linux?

[@ironwheal]

someone has way too much free time on their hands.

[@MarcinKralka]

I am currently researching how Intel 4004 works for fun. It is fascinating how different it is from later processors, since even writing a single 4-bit value to RAM takes many CPU cycles (I think it is designed to mostly work on regsiters, and there are 16 of these). I am looking forward to read that article on how did Dmitry boot up Linux on 4004. It is crazy!

[@gcolombelli]

HP also made some quirky CPUs they used on some calculators and computers, like the Nut, the Saturn and the Capricorn. The Coconut / Nut was used in the 41, 12, 15, 16, 11 calculators, it was a bit-serial CPU that addressed individual nibbles and had 56 bit wide registers where it mostly did BCD math, the Saturn is similar to the Nut, but it had 64 bit wide data registers, 20 bit wide address registers and operated one nibble at a time, instead of one bit at a time. You can't call any instruction on any pairs of registers, only the C register could be used with most other registers, except on the emulated Saturn+ that run on the 49g+ and 50g models, which use ARM SoCs. The Saturn was used in the 71B, which ran BASIC, and also the 42S, which had an upgraded 41C style programming model, the 28C and 28S, which ran RPL, as well as the 48S and 48G series. I know next to nothing about the Capricorn, but I vaguely remember it being weird like these other two (perhaps even weirder). The Capricorn was used in the HP Series 80 microcomputers. IIRC you can emulate the 85 (Capricorn) on MAME and there are various emulators for the Nut and Saturn based calculators. There are also tons of documentation on some of these calculators and processors. There's even a modern FPGA version of the Nut called Newt. If you like to play around with weird CPUs, you might like these.

[@YellowRambler]

The next logical step would be to build Charles Babbage mechanical computer and take the next 5 years to boot up Linux. This is the time someone would sacrifice a very expensive microphone by extending his hand outward horizontally and dropping the microphone 🎤 on the floor.

[@paulsander5433]

Yeah, but how will you get Ada to do the port? She's the only one who's written for that particular architecture.

[@Phil-D83]

4 or 5 days to start up on the 4004 is funny

[@TheHelvetican]

Will it run cataclysm dda?

[@humpa-pa9344]

still not on z80? ... :( kidding )

[@beSafeSafeEverywhere]

Computer science at it's peek

[@anonamouse5917]

13:58 I believe it's spelled 'Nybble'.

[@ingusmant]

Now get it to boot on the F14s processor.

[@fotoschopro1230]

But why?

[@mrudo8663]

What kind of cpu is in use by the voyagers satellites?

[@Zamsky39]

Rca 1802

[@LTPottenger]

Just goes to show it's unimaginale how much bloat there is in some of the larger OSes. But keep in mind a huge amount of memory is lost due to mapping 32 or 64k at a time in the modern OS.

[@gnuemacs1166]

Linux copied the scheduler from the sinclair Ql Unix ram on a 68000 and Linux can’t

[@cybernit3]

For AmigaOS the Exec.library was taken from some other British OS I think and was written BCPL.

[@gnuemacs1166]

@@cybernit3 tripos

[@cybernit3]

@@gnuemacs1166 Ya that is it and I recall Carl Sassarath worked on it. AmigaOS was ahead of Apple and M$ with pre-emptive multitasking; wonder what would happen if they ported it to intel.. But luckily Linus brought us an alternative to Apple/M$.

[@MorgothCreator]

Someone need to build linux for one instruction CPU's 😅

[@dmitrygr]

I am working on it.

[@MorgothCreator]

@@dmitrygr Noice 😍

[@bogganalseryd2324]

Could it run on nes?

[@tyrgoossens]

The nes has a 6502 processor too, so yes.

[@mytech6779]

I wonder how fast you could make a 4004 with a modern manufacturing node. Seems like something Intel should make a short run of for the PR. Poor IPC but I bet it could hit 7GHz

[@Zamsky39]

I bet it could be easily emulated with an fpga, maybe not 7GHz but still.

[@myne00]

Wouldn't a PIC be enough?

[@mytech6779]

@@Zamsky39 Did I say emulate?

[@mytech6779]

@@myne00 Enough to what?

[@Ensue85A]

OMG this is freakin' AWESOME!

[@МаксимСоколов-д4я]

Total bs. Unix on 8086 was Minix. And Linux was explicitly on 80386 or better

[@cybernit3]

But didn't Linus basically took Minix and expanded upon it?

[@МаксимСоколов-д4я]

@@cybernit3 How about if you read the article of the MINIX creator about why Linux is obsolete? You can find it in the internet

[@SobieRobie]

Unix started his life on PDP-7. No challenge here.

[@666Maeglin]

This level of self torture reminds me of climbing mount everest naked just wearing a sock, with 100 kg of rocks in your backpack, just to see if you can be the first person to do it.

[@semibiotic]

They do NOT run Linux, they just run a RISC-CPU emulation ...

[@ladronsiman1471]

Next Linux running on a Olivetti mechanical calculator ..

[@YadraVoat]

17:44 -We do what we must, because, we can.