This is the second video in a series where I demonstrate how I managed to extract the software from the long lost Apollo Guidance Computer used in Flight AS-202.
You just happened to know someone who owned a hospital with an X-ray machine. These modules couldn't have fallen into the hands of anyone better than you!
Looking at the "girls" threading that wire through the cores brings back memories of factory work. Haven't thought about that sort of tedium, boredom and drudgery in ages. Once upon a time that was considered a GOOD job!
Brian Bixby --- yeah, now those types of jobs are now done in China, like at Foxconn. Only difference, Predatory Capitalist now run everything, and drive people to suicide, by jumping of their building, at jobs like those at Foxconn. Sad, but true.
So what in Hell would be the proper name to identify the adult human female that would not offend the whinny little snot nosed baby's that seem to find wrong in anything and everything? The word ' girl ' inspires affection. (endearing). Maybe a potential baby producing meat bag would be better. Someone rescue the human race before we self destruct!
Bravo sir! You should probably submit these to a high resolution CAT scan, similar to the procedure used to reverse engineer the ancient Greek Antiythera device. The scan provided enough detail to not only reconstruct the device, which had rested in sea water for two millenia, but to determine that it was a very accurate mechanical celestial navigation computer. It was even detailed enough to reveal the metal working procedures used by the ancient Greeks.
This brings back a lot of memories. The Apollo series flight computers deserve need to be preserved as historical items instead of tossing them out. Keep in mind the entire space program ran mostly with slide rules also. Amazing what has changed in around 50 years as a result of the moon missions. Im convinced it was the best thing the government ever spent money on. Almost every thing to do with computers and communication today can be traced back to this project. Core was still in common use when I started to get involved in the computer field. The only difference, other than packaging , it was set up as read/write, basically just a different threading method A typical 16 bit mini computer cpu with a 32 k addressing range was around 16 inches square and 2 or 3 single sided boards high set up as a main board with daughter boards. The micro coding in one I was most familiar with was a daughter board roughly 7 inches wide by close to 16 inches long and as tightly packed as possible with mostly mask programmed roms..
some calculations could have been done by Newton centuries age. Orbital mechanics themselves aren't actually THAT complicated. But they also had 3 massive IBM computers on the ground... Most calculations were made on the ground and sent up. As it's the sensible method to this day. And the original concept of a fully autonomous on board computer was killed by technical limitations and the schedule. so the final thing was a compromise. Still mighty impressive.
Wonderful history but I think we will be surprised at who gets triggered as they went to the moon to bring back technology greatly superior to anything we have today as well. There is a reason for our acceleration in the 50 yrs it was not by accident or by trial and error as it had been since the time of the steam engine.
Fascinating memory modules. I learned about these at college in the late ‘70s. This ‘software’ is meaningless without knowing what was reading it, and how it was read. Even having the instruction set wouldn’t help without knowing what hardware it was connected to.
Hi Charles. Fortunately all the technical information on the instruction set as well as the computer design documents are publicly available. There is also a fully functional virtual Apollo Guidance Computer that is able to execute the Block I instructions contained in these modules. Lastly, the memory modules that you learned about in college were most probably Magnetic Core Memory which is a completely different technology to rope memories :-)
Magnetic Core Memory, they taught us all about this when I went to advanced ( at the time ) electronics school when I was in the Navy. Neat, I didn't think this stuff still existed.
Thanks Brian. The Apollo Guidance Computer (AGC) did use Magnetic Core memory for its RAM, but the Rope Memory (ROM) you see in this video was a very different technology and was used to store the programs. The cores in the rope memory were actually tiny transformers with the zeros and ones encoded in the wiring and not stored as magnetic fields as with Magnetic Core memories.
@@AuthGate No sir, I am not confusing. There is no way to make working this dumb idea. It can't work. Just give me the therorical schematic a two core rope memory with 128 wires passing or not in the first and the second, with the adressing and refresment logic, to make a 256 bit memory. In this case ou allready needed 128 address lines. Even if this could be done on the table, the software development and mechanical wiring is totaly unpractical to make for 64 kilobytes storage. Even, in Apollo 11, the genius pilot Neil Armstrong, following the alledge history, landed the LEM manualy, after the computer feiled to work. If it was technicaly a good system, the core rope memory would have been developped in the computer industry. This was never the case, the only working core memory is the standard core memory.
@@degrangier Just because you don't understand how something works doesn't mean it doesn't work. The cores in a rope memory are just a bunch of tiny transformers with a single primary "winding" and multiple secondary "windings". You pulse the primary winding and then sense 16 of the secondary windings. This gives you a 16 bit word. How do you address more cores and select for 16 out of 128 windings? It would be too much to type here, but in short: 1. By using additional "core de-selection" wires they can de-magnetise all but one core so you only see the influence of a single core. 2. Using a bunch of diodes, they bias a set of 16 wires out of a group of 128 wires (called a strand) with a voltage higher than a diode's forward voltage drop and "magically" only that strand's pulses appears on the output. It is really amazing how this works and I can confirm that it works quite well. The technology was used in a few mainframes and even a 1970's calculator but the cost to manufacture rope memories was too high and cheaper ROM was developed later. Finally, Neil Armstrong did not land the Lunar Module without the computer. He landed it manually, using the controls that were connected to the computer. It wasn't humanly possible to control all the thrusters with sub-second precision by hand.
Thank you sir. This is helped me release some of my regret of dropping out of computer science in 83'. Lol Still bores me to death. I am to visual rather than a linear thinker. But, this is a visual presentation I can easily understand. The advancements we have made. Typing this on a wireless keyboard, received by a Lenovo tower with 50 ram and 1 tera. Now, I am studying physics and an Electric Universe theorist. Peace and love, appreciate the knowledge I walked away from years ago.
For additional information on Core memory, circuits (and those diodes): Electronics: Magnetic Cores I: Properties (1961) US Army Training Film Electronics: Magnetic Cores II: Basic Circuits (1962) US Army Training Film
The videos you mention actually describes a different technology that was used to create RAM (read-write) memory. Rope Memories are actually very different from the more common Core Memory. The biggest visual difference is the number of wires threaded through the cores. Core memories typically have only three wires going through each core and store a single bit per core. The cores in the Rope memories could easily accommodate 100 or more wires and didn't used the cores for storing data.
what's boggling about this is, figuring out the stuff that had to be manufactured first to manufacture this. the configuring and automating had to be done with mostly pencil, paper, slide rules and tape measures!
Who are the SIX people on RUclips at the time of me making this post (10.4.17) that suck so much to actually give it a downvoted????. You downers suck! This is super cool stuff. I like your videos keep it up! 👍👍👍👍
I wholeheartedly agree with you. These youngsters take modern technology for granted, and they obviously are unable to comprehend, that modern electronic marvels are all the results of some smart people decades ago!
Prof. MO Zeee JCD ECS - I totally agree with you. I'm only 34 but that's old enough to rember having my parents get me a Commodore 64 (loading 3 to 6 data cassette tape just to play a game) as my first computer. My second one was a second hand device I think it was either a 386 or 8086 too long to remember. My first "modern" PC that ran Windows 95(!!!) I think was a Company Presario with a 100 or 133 MHz processor that we splurged on and got a whopping 3GB HDD & 32MB(lol) of RAM that computer cost us $3-4K at the time! I broke it once and parents told me that was the one and only time they pay to have it fixed. This got me into working on and troubleshooting computers as is my job I've had at a huge company for almost half my life now. We had AOL1.0 which was junk but the only internet really available other than my friends MSN dialup connection we shared to play games without AOLs lag and resource usage. I never got an allowance but talked my parents into upgrading the RAM to either 64 or 128MB (lol x2) for a few hundred dollars! Man with the low lag I LOVED playing the original War& StarCraft online owning everyone. The computer tech older than I am is just so freaking amazing how brilliant the early tech engineers were learning about it never gets old.
hehe , I had a c64 and it was an amazing computer. My original computer used a regular cassette recorder and you had to listen to that screech while it loaded (zx81). It's culture shock (I believe) that seems to make some people so touchy that everything annoys them and they feel empowered to dislike everything and feel worthwhile.
Mike Young - I have people I work with in their 20s that didn't even know non-laser mice existed haha. I don't work general desktop support at my company I do IT for a specific department I manage our users workstations with our special GPOs for our devices, but as with all corporate IS departments the PCs are desktops device so but all the software on the machines are mine. Honestly I'm glad not having to do their job. I deal no with everything corporate IT but there are many teams that specialize with their thing like security, network, desktop, and on. With 20k PCs you need that. Anyway to my coworker I'm helping with something off site, his mouse (laser) died, but being a small site we had no spares around... Other than my trunk. It's like a parts store. I have everything from a whole PC down to just about every part... Except for an optical mouse or processors or motherboards ... so guy got a PS2 ball mouse hahah. Took desktop 2 weeks to replace it because he was working. They interoffice it back to me. Never know when you might need random parts for fixing stuff. He emailed and called complaining about how crappy it was LOL. Told him to clean it which confused him until I explained the workings of the mouse and told him to clean his desk well and put a cloth mouse pad. He was ok after that.
Jetzt weiss ich, wo der Ausdruck "Ein Programm zusammenstricken" herkommt :-D (In Germany, we sometimes say colloquially "To knit a program"... now I know the source of this)
Hi Francois, very good work! In order to get a more accurate internal module view I'd suggest you to look for an Industrial tomography equipment. It will provide you a 3D model of all internal parts. Try to contact a Nikon Metrology representative. I'm pretty sure it will make the service for free for you.
it seems like i had watched the manufacturing description part in a better clarity quality on another video here on youtube. The two women sewing the cores.
I seen someone had the actual blueprints for these and the test equipment used to test each module. Did you get a copy to build yours? As this was not one of those Oh shit I screwed up and melted the wires... I still find it strange they had a limited it to 192.. Which is the magic number for video card makers on some models...As most use 128 bit even today 50 years later...
OK, you got the modules. there is a Saturn V at the Cape, command modules here and there at various museums. I believe that LM at Smithsonian is a flight ready backup. Maybe get all these pieces together (along with a bunch of other stuff I can't think about at the moment), and return to the Moon?
We don't have the technicians anymore. :( The kind of genius and specialized skills needed to operate and maintain those space craft are far on their way to oblivion, the only people who could make it work again are very old.
It sound very cool I would say... But picking up a rocket from the museum is not the only thing you would need... One thing is sure though: Everyone would kill to re live a Saturn V launch again, specially the new generations like me!
@@andrewyoung4473 and to add, there were many, many technical notes that were never wrote down, just stored in many a technician's heads, which many are dead now. Easier to build a 21st century version of the Saturn V.
"65,000 pieces of information." I assume that each "piece" is a bit, or BInary digIT (1[on] or 0[off]). That would be almost 8 kilobytes per rope memory module.
You are 100% correct Mark. Note that these modules were used on the Block I computer. The Block II computer that were used on the Moon missions used higher capacity rope memories with 50% more storage (65536 + 32768 = 98304 bits). It is also interesting to note that the data is organised in 16 bit words (15 data bits and 1 parity bit), so the there are actually 4096 memory locations per module.
I had never before considered it (I have yet to have any South Africa as a setting in anything I've written) but every setting I use, I try to research the common names in that area for authenticity. "Dirk Pretorius" is just so instantly recognizable as South African that I just may have to use it... great name.
Do the number of wires threaded through each core translate directly to the number of 'hard wired' methods / functions that a particular modules is capable of executing?
Each core can accommodate 128 wires. These wires are divided into 8 strands of 16 wires each. One strand of 16 wires is equivalent to 16 bits and represent a single instruction, like add, compare, jump, etc. So one core stores 8 individual instructions.
Fascinating stuff, thank you :) Is it possible the two extra diodes performed a backup/fail safe function of some kind, perhaps limited to a critical process?
It could be, but they already had a number of other fail safe mechanisms like data parity and memory checksums. Your question made me think whether these diodes could maybe have something to do with the factory testing of the modules. There are 4 connection pins on the modules that I have not been able to identify yet and these may very well play some part in this too.
Copies of the software existed as flow charts. Cross disciplined systems engineers did not exist at the time, engineers who understood the calculations understood flow charts.
there is another great video about the flight computer and it contains some information about the rope memory modules : ruclips.net/video/9YA7X5we8ng/видео.html
Have you figured out yet how the rope memories actually worked? If the memory bits were encoded in the arrangement of the sense wires, why did they need magnetizable cores?
I have 98% of it figured out and have actually started making a video describing the technical aspects. Unfortunately I have been a bit busy the last year, but I promise that I will publish this in the coming months.
You still need a way to couple the field from the address wire to the sense wire. So the rope memory cores are just tiny transformer cores and not permanently magnetized as the core memory cores are.
I am just wondering how much was working this Apollo calculator. Worst case, just looking nice on the dashboard of the LEM, showing some numbers or words on the display unit. Assuming they needed 64 Ko of memory to run the software, that means at least 524280 cores. Of course, the currant needed to drive each core plus the weight of the logic components would have been out of specifications. So what? At least for the ROM (Read Only Memory) where was stored the system software could crunch the requested number of core by re-using the cores by passing the sensing wires where there is one core set as zero or set to one. That means, assuming we dare to pass up to 192 wire in a tiny core hole, it would need 2730 cores. No need to say, for a system engineer, the burden of programming and testing such a calculator. A minor modification of the source program, and you have to pass again all the 524000 wires manually. Less cores, but a lot more writing and reading components. A little bit less if the scratch memory is included in the 64 ko. Of course, the scratch memory cannot use the 192 wires in one core, because you write variable data and you don't know where you get a one or a zero. I am very doubting you can functionally arrive to conceive a working development tool which will compile the wiring as a known version of the developed software will have its own full hand-wiring process. And in a very short time range. Having long system engineering and software development since before 1980, I was at electronic university in 1968, I will be completely baffled if this calculator was really able to guide and land the LEM safely to the moon and back to earth. Much more to say following the Apollo 11 story, but this is another story.
@@AuthGate : One thing I am sure, we didn't got the real full story from Nasa. Now, how far we went to the moon, I dont know. As an engineer, I measure the huge effort. We have something that looks credible on the paper and other things looking for me very doubtful. In fact, really, I didn't have yet got the 100% scientific proof that will convince me that they did really as told. May be you have, do you?
@@degrangier OK, so you have some doubts. Let's start with the software development process. (1) The software was written on paper first. That was common practice. (2) Once they were happy that it would be relatively bug-free, it was compiled on a mainframe into AGC machine code. (3) The compiled code was then downloaded from a minicomputer into a rope memory emulator. (4) they could then run and test the code on an actual AGC in realtime. The whole process could be repeated in a few minutes. The rope memories were only manufactured when they were happy that everything worked correctly. Btw, there weren't 524280 cores. They could store 192 bits in a single core. Some of these bits were zeros and the rest were ones. Only the ones were threaded through the cores, so on average only 96 wires passed through a core. There were 36864 words of 16 bits each. I will leave it to you to calculate the number of cores. If you cannot imagine a way for this to work, then you should be humble and have respect for those clever engineers who managed to make this work. So you see, real engineers are very pragmatic folk. We figure out how to break difficult problems into smaller problems and then solve the smaller problems. If you were a *real* engineer, then you would understand this and be able to figure these things out for yourself. I cannot "prove" to you that NASA went to the moon, but I can see how all this was possible and I know engineers and understand the pride they take in their work. These people didn't do it for the money. They did it because they wanted to go to the Moon. They made mistakes, fixed it, and tried again until everything worked as good as was humanly possible. They went to the Moon 9 times and landed 6 times. All the evidence is there. You just need to open your eyes.
Paul Degrangier If you are doubting or making a claim, it is up to YOU to provide proof for that claim, not the person to whom you are expressing or stating the claim.
It wasn't a "calculator" -- it was an embedded computer to control the ship. My understanding is that some big number crunching was done on earth at NASA flight HQ by IBM mainframes, with data being sent back and forth via the telemetry system.
Quite a bit has happened in the last few months. Some guy discovered a complete copy of the block 1 AGC circuit diagrams in his grandfather's garage. We are still working through the new info, but it looks very promising. I was almost ready to post five new videos when the new info came to light. I will post updates in the next few weeks.
Can't wait! I teach high school computer science classes and I couch a lot of my curriculum in the Apollo program and computer history. We are actually building a DSKY replica, so we're waiting for updates with baited breath!
You can think of the cores as little transformers but instead of just a primary and secondary winding, each core could have a hundred (or more) secondary coils. Also, instead of multiple windings per coil, you only need to thread a wire through the core. It is not an efficient transformer but it is good enough. In an over simplified example, you would send a pulse through the primary "coil" and measure which secondary "coils" pick up the signal. These would be the "ones" as the "zeros" would not be threaded through the core. In practice, it is a little more complicated. I should maybe do another video to explain this in more detail.
Lol, okay, I see now you already found that video. My main question, obviously, is how the hell do you store 65,000 bits (65,535?) using 512 cores... :-/ Maybe I'm not understanding what he's trying to say correctly.
The cores don't actually store the bits as is the case with core memory (RAM). The cores are used as little transformers that "reveal" the wiring of the memory. Each core can be (theoretically) threaded with as many 128 wires. There is a clever mechanism by which you can enable a subset of 16 wires (a strand). You can also disable all but one core, by saturating these cores with an inverse polarity pulse. The single isolated core is then "pulsed" and the 16 isolated wires (selected strand) are sensed to determine if they are threaded through the core or not. In short, each core can sense 128 bits (16 bits in 8 strands). With 512 cores, you then have 128 * 512 = 65536 bits.
He said it has 512 cores. each core is either 1 or 0 , meaning its 512 bits, each byte consists of 8 bits. making each module have a total memory of 64 bytes. 1 kilobyte is equal to 1024 bytes, so it would take 16 of these to equal one kilobyte of memory. to put than into perspective 1 gigabyte is equal to 1 billion bytes. and the computer i am typing this with has 20 gigabytes of just RAM and another 4000 gigabytes of HDD space. roughly 62,812,500,000 times as much memory in much less physical space. amazing how for this technology has come since then..
I suspect they may be sharing some cores between multiple bits/bytes, not as straight forward as one core per bit. also not necessarily 8 bits in a byte but is common.
The memory data in this case is literally wired in. As long as the circuit remains in place, there's the data right there. "Writing" data to such a system entails rewiring.
Hi, The circuit modules you show about 3/4 of the way thru are from a Burroughs Line Printer, circa 1970's I believe. See ruclips.net/video/n-pfM7N8XzE/видео.html for details Best regards, Bart
I was once having lunch with the Marketing Director of the UK's second biggest corporation. He told me he was interviewing for a new secretary because his 'girl' had left. I asked him why she left. "She retired".
They were either added to bill the taxpayer more, was redundancy, or were added as an original design fuck up or it was just cheaper to make it all in a grid array.
you obviously are too young to appreciate this ;-) and therefore take many technologies for granted, but remember, all modern technology is based to a large extent on this "little old lady"... Dude!
Il faut voir cette vidéo: ruclips.net/video/2KSahAoOLdU/видео.html Ceci démontre bien ce que j'avais pressenti en ce qui concerne la fameuse "Core rope memory", que c'était juste irréalisable. On a jamais vu un ordinateur de bord Apollo équipé de ce type de mémoire. De fonctionnel, il n'y avait que la mémoire à tores classique, ce qui ne permettait pas d'avoir la capacité de stockage suffisante pour des programmes de calcul élaborés. Il est curieux de voir dans l'équipement présenté ici, un "simulateur" de "core rope memory", comportant des circuits intégrés, apparemment de type TTL qui n'existaient pas encore avant 1970. De plus, ce prototype, intègre ces circuits sur des barres de contacts non soudées, ce qui n'est pas acceptable en opérationnel dans ce type d'application spatiale.
And yet in today's USA the "girls" would be protesting outside. "Oh what, because i'm a woman you have to give me a needle? Is that it, you just assume that because i have a vagina i am automatically good with sewing needles?!?!"
1) Samantha is not a real person... 2) He didnt say anything about woman being not able to handle this work because of woman physiology. 3) Avarage woman is much more efficient in work like that (high precision operations with small objects) thats why they didnt hire any man for this. Today if you admit to the guy that is looking for job that you prefer woman because they are better for it you can end up in front of a judge that gonna force you to pay huge ammount of money for not being brainwashed properly... So in the end it will be hard for you to find job like this or any similar lab job if you are a man but no one gonna tell you why he is not willing to hire you. :P
56 yo computer geek with 30+ years in the field and yes, that is exactly what I thought when I saw these "girls" operating the needles to thread the cores - they're girls so they are better suited to needle wires around cores because they are presumed to have sewing skills? Then my next thought was to think there are young millenial men in the US today who think all the troubles in the US now are because women were given the right to vote. Um. Girls in the 60's could be trusted to build memory cores to send up the Apollo missions successfully, but now cannot be trusted to cast a proper vote? We really have devolved as a society.
You just happened to know someone who owned a hospital with an X-ray machine. These modules couldn't have fallen into the hands of anyone better than you!
This is like archeology of computers. Great work.
It is actually called "Techno Archeology"
some call it Media Archeology
Looking at the "girls" threading that wire through the cores brings back memories of factory work. Haven't thought about that sort of tedium, boredom and drudgery in ages. Once upon a time that was considered a GOOD job!
Brian Bixby --- yeah, now those types of jobs are now done in China, like at Foxconn.
Only difference, Predatory Capitalist now run everything, and drive people to suicide, by jumping of their building, at jobs like those at Foxconn.
Sad, but true.
Same jobs are still here..but in China..until robots take over.
"Girls". He was so not woke and such a casual sexist, try that now and you will get told off if not sued. Lol.
@@Folker46590 As it should be. Condescending bullshit then, still condescending bullshit now.
So what in Hell would be the proper name to identify the adult human female that would not offend the whinny little snot nosed baby's that seem to find wrong in anything and everything? The word ' girl ' inspires affection. (endearing). Maybe a potential baby producing meat bag would be better. Someone rescue the human race before we self destruct!
Bravo sir! You should probably submit these to a high resolution CAT scan, similar to the procedure used to reverse engineer the ancient Greek Antiythera device. The scan provided enough detail to not only reconstruct the device, which had rested in sea water for two millenia, but to determine that it was a very accurate mechanical celestial navigation computer. It was even detailed enough to reveal the metal working procedures used by the ancient Greeks.
Thank you again for your wonderful work on this conservation of history.
This brings back a lot of memories. The Apollo series flight computers deserve need to be preserved as historical items instead of tossing them out. Keep in mind the entire space program ran mostly with slide rules also. Amazing what has changed in around 50 years as a result of the moon missions. Im convinced it was the best thing the government ever spent money on. Almost every thing to do with computers and communication today can be traced back to this project.
Core was still in common use when I started to get involved in the computer field. The only difference, other than packaging , it was set up as read/write, basically just a different threading method A typical 16 bit mini computer cpu with a 32 k addressing range was around 16 inches square and 2 or 3 single sided boards high set up as a main board with daughter boards. The micro coding in one I was most familiar with was a daughter board roughly 7 inches wide by close to 16 inches long and as tightly packed as possible with mostly mask programmed roms..
fascinating! tx for sharing
some calculations could have been done by Newton centuries age. Orbital mechanics themselves aren't actually THAT complicated. But they also had 3 massive IBM computers on the ground...
Most calculations were made on the ground and sent up. As it's the sensible method to this day. And the original concept of a fully autonomous on board computer was killed by technical limitations and the schedule. so the final thing was a compromise. Still mighty impressive.
Wonderful history but I think we will be surprised at who gets triggered as they went to the moon to bring back technology greatly superior to anything we have today as well. There is a reason for our acceleration in the 50 yrs it was not by accident or by trial and error as it had been since the time of the steam engine.
Fascinating memory modules. I learned about these at college in the late ‘70s. This ‘software’ is meaningless without knowing what was reading it, and how it was read. Even having the instruction set wouldn’t help without knowing what hardware it was connected to.
Hi Charles. Fortunately all the technical information on the instruction set as well as the computer design documents are publicly available. There is also a fully functional virtual Apollo Guidance Computer that is able to execute the Block I instructions contained in these modules. Lastly, the memory modules that you learned about in college were most probably Magnetic Core Memory which is a completely different technology to rope memories :-)
Magnetic Core Memory, they taught us all about this when I went to advanced ( at the time ) electronics school when I was in the Navy. Neat, I didn't think this stuff still existed.
Thanks Brian. The Apollo Guidance Computer (AGC) did use Magnetic Core memory for its RAM, but the Rope Memory (ROM) you see in this video was a very different technology and was used to store the programs. The cores in the rope memory were actually tiny transformers with the zeros and ones encoded in the wiring and not stored as magnetic fields as with Magnetic Core memories.
@@AuthGate stupid ! learn first how it works here : en.wikipedia.org/wiki/Magnetic-core_memory
@@degrangier you are confusing core memory with rope memory. The link you provided are for core memory (RAM).
@@AuthGate No sir, I am not confusing. There is no way to make working this dumb idea. It can't work. Just give me the therorical schematic a two core rope memory with 128 wires passing or not in the first and the second, with the adressing and refresment logic, to make a 256 bit memory. In this case ou allready needed 128 address lines. Even if this could be done on the table, the software development and mechanical wiring is totaly unpractical to make for 64 kilobytes storage. Even, in Apollo 11, the genius pilot Neil Armstrong, following the alledge history, landed the LEM manualy, after the computer feiled to work.
If it was technicaly a good system, the core rope memory would have been developped in the computer industry. This was never the case, the only working core memory is the standard core memory.
@@degrangier Just because you don't understand how something works doesn't mean it doesn't work.
The cores in a rope memory are just a bunch of tiny transformers with a single primary "winding" and multiple secondary "windings". You pulse the primary winding and then sense 16 of the secondary windings. This gives you a 16 bit word.
How do you address more cores and select for 16 out of 128 windings? It would be too much to type here, but in short:
1. By using additional "core de-selection" wires they can de-magnetise all but one core so you only see the influence of a single core.
2. Using a bunch of diodes, they bias a set of 16 wires out of a group of 128 wires (called a strand) with a voltage higher than a diode's forward voltage drop and "magically" only that strand's pulses appears on the output.
It is really amazing how this works and I can confirm that it works quite well. The technology was used in a few mainframes and even a 1970's calculator but the cost to manufacture rope memories was too high and cheaper ROM was developed later.
Finally, Neil Armstrong did not land the Lunar Module without the computer. He landed it manually, using the controls that were connected to the computer. It wasn't humanly possible to control all the thrusters with sub-second precision by hand.
This is really amazing. Thanks Francois, keep it up.
Thanks Francois for uncovering these hidden gems.
Thank you sir. This is helped me release some of my regret of dropping out of computer science in 83'. Lol Still bores me to death. I am to visual rather than a linear thinker. But, this is a visual presentation I can easily understand. The advancements we have made. Typing this on a wireless keyboard, received by a Lenovo tower with 50 ram and 1 tera. Now, I am studying physics and an Electric Universe theorist. Peace and love, appreciate the knowledge I walked away from years ago.
I cannot sing or play an instrument but I can still enjoy good music. Appreciation for something is also a skill. Good luck with your endeavors.
> 50 ram
> 1 tera
What type of processor do you have? 9 giga ?
yeah was wondering as well....50 ram???
For additional information on Core memory, circuits (and those diodes):
Electronics: Magnetic Cores I: Properties (1961) US Army Training Film
Electronics: Magnetic Cores II: Basic Circuits (1962) US Army Training Film
The videos you mention actually describes a different technology that was used to create RAM (read-write) memory. Rope Memories are actually very different from the more common Core Memory. The biggest visual difference is the number of wires threaded through the cores. Core memories typically have only three wires going through each core and store a single bit per core. The cores in the Rope memories could easily accommodate 100 or more wires and didn't used the cores for storing data.
Francois Rautenbach The biggest difference is that rope memory couldn’t work with square loop ferrite.
It must of been difficult for those girls to see what they were doing in that dim black and white light in those days.
Francois, I can't wait for the next update. You're truly an amazing person.
what's boggling about this is, figuring out the stuff that had to be manufactured first to manufacture this. the configuring and automating had to be done with mostly pencil, paper, slide rules and tape measures!
for me, it was the punched tape-driven weaving machines that were probably as amazing as the technology at the time.
@@azzajohnson2123 : Yes.
amazing video and information.! thanks for taking the time. Can we expect video #3 at some point?
So awesome! Someone give this guy a medal !!!
*boy
Incredible, physical rope memory.
Who are the SIX people on RUclips at the time of me making this post (10.4.17) that suck so much to actually give it a downvoted????. You downers suck! This is super cool stuff.
I like your videos keep it up! 👍👍👍👍
I wholeheartedly agree with you. These youngsters take modern technology for granted, and they obviously are unable to comprehend, that modern electronic marvels are all the results of some smart people decades ago!
Prof. MO Zeee JCD ECS - I totally agree with you. I'm only 34 but that's old enough to rember having my parents get me a Commodore 64 (loading 3 to 6 data cassette tape just to play a game) as my first computer. My second one was a second hand device I think it was either a 386 or 8086 too long to remember.
My first "modern" PC that ran Windows 95(!!!) I think was a Company Presario with a 100 or 133 MHz processor that we splurged on and got a whopping 3GB HDD & 32MB(lol) of RAM that computer cost us $3-4K at the time! I broke it once and parents told me that was the one and only time they pay to have it fixed. This got me into working on and troubleshooting computers as is my job I've had at a huge company for almost half my life now.
We had AOL1.0 which was junk but the only internet really available other than my friends MSN dialup connection we shared to play games without AOLs lag and resource usage. I never got an allowance but talked my parents into upgrading the RAM to either 64 or 128MB (lol x2) for a few hundred dollars! Man with the low lag I LOVED playing the original War& StarCraft online owning everyone.
The computer tech older than I am is just so freaking amazing how brilliant the early tech engineers were learning about it never gets old.
hehe , I had a c64 and it was an amazing computer. My original computer used a regular cassette recorder and you had to listen to that screech while it loaded (zx81). It's culture shock (I believe) that seems to make some people so touchy that everything annoys them and they feel empowered to dislike everything and feel worthwhile.
Mike Young - I have people I work with in their 20s that didn't even know non-laser mice existed haha. I don't work general desktop support at my company I do IT for a specific department I manage our users workstations with our special GPOs for our devices, but as with all corporate IS departments the PCs are desktops device so but all the software on the machines are mine. Honestly I'm glad not having to do their job. I deal no with everything corporate IT but there are many teams that specialize with their thing like security, network, desktop, and on. With 20k PCs you need that.
Anyway to my coworker I'm helping with something off site, his mouse (laser) died, but being a small site we had no spares around... Other than my trunk. It's like a parts store. I have everything from a whole PC down to just about every part... Except for an optical mouse or processors or motherboards ... so guy got a PS2 ball mouse hahah. Took desktop 2 weeks to replace it because he was working. They interoffice it back to me. Never know when you might need random parts for fixing stuff. He emailed and called complaining about how crappy it was LOL. Told him to clean it which confused him until I explained the workings of the mouse and told him to clean his desk well and put a cloth mouse pad. He was ok after that.
Jetzt weiss ich, wo der Ausdruck "Ein Programm zusammenstricken" herkommt :-D
(In Germany, we sometimes say colloquially "To knit a program"... now I know the source of this)
Sehr interestig. Vielen Dank :-)
That's bullshit of course, but hey, it sounds good.
R.I.P. John Fitch
Hi Francois, very good work!
In order to get a more accurate internal module view I'd suggest you to look for an Industrial tomography equipment. It will provide you a 3D model of all internal parts. Try to contact a Nikon Metrology representative. I'm pretty sure it will make the service for free for you.
it seems like i had watched the manufacturing description part in a better clarity quality on another video here on youtube. The two women sewing the cores.
Here is the rest of that documentary shown in this video:
ruclips.net/video/ndvmFlg1WmE/видео.html
I seen someone had the actual blueprints for these and the test equipment used to test each module. Did you get a copy to build yours? As this was not one of those Oh shit I screwed up and melted the wires...
I still find it strange they had a limited it to 192.. Which is the magic number for video card makers on some models...As most use 128 bit even today 50 years later...
OK, you got the modules. there is a Saturn V at the Cape, command modules here and there at various museums. I believe that LM at Smithsonian is a flight ready backup. Maybe get all these pieces together (along with a bunch of other stuff I can't think about at the moment), and return to the Moon?
k6mfw --- you only need a million gallons of fuel then 😃
We don't have the technicians anymore. :(
The kind of genius and specialized skills needed to operate and maintain those space craft are far on their way to oblivion, the only people who could make it work again are very old.
It sound very cool I would say...
But picking up a rocket from the museum is not the only thing you would need...
One thing is sure though: Everyone would kill to re live a Saturn V launch again, specially the new generations like me!
@@andrewyoung4473 and to add, there were many, many technical notes that were never wrote down, just stored in many a technician's heads, which many are dead now. Easier to build a 21st century version of the Saturn V.
"65,000 pieces of information." I assume that each "piece" is a bit, or BInary digIT (1[on] or 0[off]). That would be almost 8 kilobytes per rope memory module.
Having watched it a second time, I see my answer in the photographs--"65,536 bits". That equals exactly 8kilobytes/module.
You are 100% correct Mark. Note that these modules were used on the Block I computer. The Block II computer that were used on the Moon missions used higher capacity rope memories with 50% more storage (65536 + 32768 = 98304 bits). It is also interesting to note that the data is organised in 16 bit words (15 data bits and 1 parity bit), so the there are actually 4096 memory locations per module.
I had never before considered it (I have yet to have any South Africa as a setting in anything I've written) but every setting I use, I try to research the common names in that area for authenticity. "Dirk Pretorius" is just so instantly recognizable as South African that I just may have to use it... great name.
Duuude, what has this to do with the content of the video??? Are you are smoking something...
“let’s look at the girls thread the cores” lolol
How do you fix a wiring error??
that's pretty exciting!
PogChamp, awesome work
Do the number of wires threaded through each core translate directly to the number of 'hard wired' methods / functions that a particular modules is capable of executing?
Each core can accommodate 128 wires. These wires are divided into 8 strands of 16 wires each. One strand of 16 wires is equivalent to 16 bits and represent a single instruction, like add, compare, jump, etc. So one core stores 8 individual instructions.
***** amazing!
Fascinating stuff, thank you :)
Is it possible the two extra diodes performed a backup/fail safe function of some kind, perhaps limited to a critical process?
It could be, but they already had a number of other fail safe mechanisms like data parity and memory checksums.
Your question made me think whether these diodes could maybe have something to do with the factory testing of the modules. There are 4 connection pins on the modules that I have not been able to identify yet and these may very well play some part in this too.
One waits with bated breath, thank you :)
even today with too much power, some space mission fail..
it is not the hardware but also the software..
that was really interesting!
Not something you want to get to the tester and find out one little wire in the middle was in the wrong place.
Awsome
Amazing
I think the two extra were for parity.
Why is it called "rope" memory rather than "core" memory?
Because it is different to core memory. Rope memory is a type of hardwired Read Only Memory (ROM) that was not very common.
Suggestion, please level your speaking voice with the videos :)
so each memory module was 8.125 bytes
512 cores times 128 bits per core = 65536 bits per module. That translates to 8192 bytes. It was a 16 bit computer though, so 4096 words per module.
i risently viewed video from 1966 with explonation about diods used in this module
64K per block..?
K bits. Done with 512 transformers. Someone thought this all out before building it too.
Did the Russians have anything comparable?
Why was it long lost? Did NASA not have paper copies of the software contained in these cores?
Copies of the software existed as flow charts. Cross disciplined systems engineers did not exist at the time, engineers who understood the calculations understood flow charts.
there is another great video about the flight computer and it contains some information about the rope memory modules
: ruclips.net/video/9YA7X5we8ng/видео.html
Part 3!!! Part 3!!!
Francois. I would love to have you on my podcast Conversations with Apollo to talk about your find. Things we can do that?
Sure, sounds like fun :-)
“The girls” - LOL indeed
Have you figured out yet how the rope memories actually worked? If the memory bits were encoded in the arrangement of the sense wires, why did they need magnetizable cores?
I have 98% of it figured out and have actually started making a video describing the technical aspects. Unfortunately I have been a bit busy the last year, but I promise that I will publish this in the coming months.
You still need a way to couple the field from the address wire to the sense wire. So the rope memory cores are just tiny transformer cores and not permanently magnetized as the core memory cores are.
Ah, I see. All the information is encoded in the routing of the sense wires.
Exactly! NASA wouldn't have been able to degauss these modules even if they tried.
Magnetic SSD ;)
I am just wondering how much was working this Apollo calculator. Worst case, just looking nice on the dashboard of the LEM, showing some numbers or words on the display unit. Assuming they needed 64 Ko of memory to run the software, that means at least 524280 cores. Of course, the currant needed to drive each core plus the weight of the logic components would have been out of specifications. So what? At least for the ROM (Read Only Memory) where was stored the system software could crunch the requested number of core by re-using the cores by passing the sensing wires where there is one core set as zero or set to one.
That means, assuming we dare to pass up to 192 wire in a tiny core hole, it would need 2730 cores. No need to say, for a system engineer, the burden of programming and testing such a calculator. A minor modification of the source program, and you have to pass again all the 524000 wires manually. Less cores, but a lot more writing and reading components. A little bit less if the scratch memory is included in the 64 ko. Of course, the scratch memory cannot use the 192 wires in one core, because you write variable data and you don't know where you get a one or a zero.
I am very doubting you can functionally arrive to conceive a working development tool which will compile the wiring as a known version of the developed software will have its own full hand-wiring process. And in a very short time range. Having long system engineering and software development since before 1980, I was at electronic university in 1968, I will be completely baffled if this calculator was really able to guide and land the LEM safely to the moon and back to earth.
Much more to say following the Apollo 11 story, but this is another story.
You clearly don't have a clue, do you?
@@AuthGate : One thing I am sure, we didn't got the real full story from Nasa. Now, how far we went to the moon, I dont know. As an engineer, I measure the huge effort. We have something that looks credible on the paper and other things looking for me very doubtful. In fact, really, I didn't have yet got the 100% scientific proof that will convince me that they did really as told. May be you have, do you?
@@degrangier OK, so you have some doubts. Let's start with the software development process. (1) The software was written on paper first. That was common practice. (2) Once they were happy that it would be relatively bug-free, it was compiled on a mainframe into AGC machine code. (3) The compiled code was then downloaded from a minicomputer into a rope memory emulator. (4) they could then run and test the code on an actual AGC in realtime. The whole process could be repeated in a few minutes. The rope memories were only manufactured when they were happy that everything worked correctly.
Btw, there weren't 524280 cores. They could store 192 bits in a single core. Some of these bits were zeros and the rest were ones. Only the ones were threaded through the cores, so on average only 96 wires passed through a core. There were 36864 words of 16 bits each. I will leave it to you to calculate the number of cores. If you cannot imagine a way for this to work, then you should be humble and have respect for those clever engineers who managed to make this work.
So you see, real engineers are very pragmatic folk. We figure out how to break difficult problems into smaller problems and then solve the smaller problems. If you were a *real* engineer, then you would understand this and be able to figure these things out for yourself. I cannot "prove" to you that NASA went to the moon, but I can see how all this was possible and I know engineers and understand the pride they take in their work. These people didn't do it for the money. They did it because they wanted to go to the Moon. They made mistakes, fixed it, and tried again until everything worked as good as was humanly possible. They went to the Moon 9 times and landed 6 times. All the evidence is there. You just need to open your eyes.
Paul Degrangier If you are doubting or making a claim, it is up to YOU to provide proof for that claim, not the person to whom you are expressing or stating the claim.
It wasn't a "calculator" -- it was an embedded computer to control the ship. My understanding is that some big number crunching was done on earth at NASA flight HQ by IBM mainframes, with data being sent back and forth via the telemetry system.
wow!!!!
Stay tuned. More info coming soon :-)
Any update on the memory and its contents?
Quite a bit has happened in the last few months. Some guy discovered a complete copy of the block 1 AGC circuit diagrams in his grandfather's garage. We are still working through the new info, but it looks very promising. I was almost ready to post five new videos when the new info came to light. I will post updates in the next few weeks.
Can't wait! I teach high school computer science classes and I couch a lot of my curriculum in the Apollo program and computer history. We are actually building a DSKY replica, so we're waiting for updates with baited breath!
@@AuthGate I was just curious if you had any updates for us on these modules or the AGC itself.
I'm still in Rope Memory class 101. How can the software be "wired" to them and, in special, how to read them?
You can think of the cores as little transformers but instead of just a primary and secondary winding, each core could have a hundred (or more) secondary coils. Also, instead of multiple windings per coil, you only need to thread a wire through the core. It is not an efficient transformer but it is good enough.
In an over simplified example, you would send a pulse through the primary "coil" and measure which secondary "coils" pick up the signal. These would be the "ones" as the "zeros" would not be threaded through the core.
In practice, it is a little more complicated. I should maybe do another video to explain this in more detail.
@@AuthGate Great, thank you for your answer. If you do a video about this would be great!
How many bits are on each module?
Lol, okay, I see now you already found that video. My main question, obviously, is how the hell do you store 65,000 bits (65,535?) using 512 cores... :-/ Maybe I'm not understanding what he's trying to say correctly.
The cores don't actually store the bits as is the case with core memory (RAM). The cores are used as little transformers that "reveal" the wiring of the memory. Each core can be (theoretically) threaded with as many 128 wires. There is a clever mechanism by which you can enable a subset of 16 wires (a strand). You can also disable all but one core, by saturating these cores with an inverse polarity pulse. The single isolated core is then "pulsed" and the 16 isolated wires (selected strand) are sensed to determine if they are threaded through the core or not.
In short, each core can sense 128 bits (16 bits in 8 strands). With 512 cores, you then have 128 * 512 = 65536 bits.
Almost 65k per Block !
By “pieces of information”, I think he meant “bits”.
yeah, so 65k, right?
is it 16 bit data? if so, 4k bytes of data
He said it has 512 cores. each core is either 1 or 0 , meaning its 512 bits, each byte consists of 8 bits. making each module have a total memory of 64 bytes. 1 kilobyte is equal to 1024 bytes, so it would take 16 of these to equal one kilobyte of memory. to put than into perspective 1 gigabyte is equal to 1 billion bytes. and the computer i am typing this with has 20 gigabytes of just RAM and another 4000 gigabytes of HDD space. roughly 62,812,500,000 times as much memory in much less physical space. amazing how for this technology has come since then..
I suspect they may be sharing some cores between multiple bits/bytes, not as straight forward as one core per bit. also not necessarily 8 bits in a byte but is common.
is it possible this memory to store data for 40 years? doen't it once readable?
The memory data in this case is literally wired in. As long as the circuit remains in place, there's the data right there. "Writing" data to such a system entails rewiring.
So Rope Memory is basically Core memory? good to know.
No, incorrect.
Sound level is bad. Please edit.
Hi,
The circuit modules you show about 3/4 of the way thru
are from a Burroughs Line Printer, circa 1970's I believe.
See ruclips.net/video/n-pfM7N8XzE/видео.html for details
Best regards,
Bart
Thanks Bart. I didn't know that. It is really interesting!
Pair of "girls" that are older than the guy talking!
I was once having lunch with the Marketing Director of the UK's second biggest corporation. He told me he was interviewing for a new secretary because his 'girl' had left. I asked him why she left. "She retired".
So what's the proper word to use? Gotta know?
sewing the cores
The "girl" is 55 years old!
They must keep that in a safe place if they lose it they cannot go to the moon lost all tegnology
Some more words of wisdom from Gertjie Gansgat...
Two extra diodes! Further proof that the whole thing is a hoax! Sarcasm
They were either added to bill the taxpayer more, was redundancy, or were added as an original design fuck up or it was just cheaper to make it all in a grid array.
They were there to support the flux capacitor -- however it hadn't been invented yet. :-)
but you didnt read the cores out.
Notice that this is "Part 2". He read them out in Part 1.
F.ck yeah, tell him!
LOL little old lady memory
you obviously are too young to appreciate this ;-) and therefore take many technologies for granted, but remember, all modern technology is based to a large extent on this "little old lady"... Dude!
All that for 64kb….
48KB (48 kilo-bytes)
@@AuthGate let’s just say that it’s a good time to be alive, or perhaps better.
Il faut voir cette vidéo: ruclips.net/video/2KSahAoOLdU/видео.html
Ceci démontre bien ce que j'avais pressenti en ce qui concerne la fameuse "Core rope memory", que c'était juste irréalisable. On a jamais vu un ordinateur de bord Apollo équipé de ce type de mémoire. De fonctionnel, il n'y avait que la mémoire à tores classique, ce qui ne permettait pas d'avoir la capacité de stockage suffisante pour des programmes de calcul élaborés. Il est curieux de voir dans l'équipement présenté ici, un "simulateur" de "core rope memory", comportant des circuits intégrés, apparemment de type TTL qui n'existaient pas encore avant 1970. De plus, ce prototype, intègre ces circuits sur des barres de contacts non soudées, ce qui n'est pas acceptable en opérationnel dans ce type d'application spatiale.
A liar will never go to heaven...
I feel so sorry for you then...
Cardiologist.....lmfao
caveman simms
And yet in today's USA the "girls" would be protesting outside. "Oh what, because i'm a woman you have to give me a needle? Is that it, you just assume that because i have a vagina i am automatically good with sewing needles?!?!"
"Just because my reproductive organs are on the inside instead of the outside doesn't mean I can't handle whatever you can handle." - Samantha Carter
1) Samantha is not a real person... 2) He didnt say anything about woman being not able to handle this work because of woman physiology. 3) Avarage woman is much more efficient in work like that (high precision operations with small objects) thats why they didnt hire any man for this. Today if you admit to the guy that is looking for job that you prefer woman because they are better for it you can end up in front of a judge that gonna force you to pay huge ammount of money for not being brainwashed properly... So in the end it will be hard for you to find job like this or any similar lab job if you are a man but no one gonna tell you why he is not willing to hire you. :P
Those who ask questions are very good in one thing... SHOPPING!
56 yo computer geek with 30+ years in the field and yes, that is exactly what I thought when I saw these "girls" operating the needles to thread the cores - they're girls so they are better suited to needle wires around cores because they are presumed to have sewing skills? Then my next thought was to think there are young millenial men in the US today who think all the troubles in the US now are because women were given the right to vote. Um. Girls in the 60's could be trusted to build memory cores to send up the Apollo missions successfully, but now cannot be trusted to cast a proper vote? We really have devolved as a society.
@@gwebocelestron9194 Are we not men? We are Devo -- D-E-V-O!
Why not take this stuff to NASA?
Who do you think threw it away in the first place?
I meant to say FAKE^FAKE^FAKE
That's more like it.