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Build Your Own Apollo Guidance Computer
PingXao writes "Well, if you can't exactly give the Moon you can give the gift of a computer to get you there. Almost a year ago this Slashdot story about the Apollo 11 Guidance Computer referenced a pretty cool Dr. Dobbs Journal article from their History of Computing series. Now there's this guy who built one in his basement! It took him 4 years, $2,980 in cash, 2,500 hours of labor and 15,000 hand-wrapped wire connections with 3,500 feet of wire to build. It might be next Christmas before you could build one of your own to give as a gift, but he promises you can build your own for less and it will be better than his. The perfect gift for the space geek who has everything. This guy is my hero."
with those old boxes, how in hell did they ever make it to the moon and back alive.
Is it fascism yet?
The other Greek gods? Don't they need guidance also?
Now all he has to do is build his own apollo 11, and he's all set to go to the moon! He just has to pay a few hundred million to get the rockets to take it up.
[me] HI AUNT EDNA! Look what I built for you! Its an exact replica of the Apollo guidance computer!
[Aunt Edna] uh, thanks?
time is a perception of a being's consciousness
time is your 6th sense, the wierd ones are 7+
I understand that it took him a long time and it's quite an incredible feat, but how is it usable/testable? Apollogize for my stupidity.
--
http://www.gamercentric.com/ - Now with a clan and tournament system!
You could just hack a Gameboy Advance, and have even more horsepower! To the MOOOOOOOOOOOOON!!!!!!!!
will it run Linux? ... or at least NetBSD?
I bet someone could write an emulator that runs on a Palm or something similar.
For that I coulda built him a computer that would take him to the moon and let him play doom3 so he wouldnt get bored on the way...
you see, I come from a time in the nineteen hundred and seventies
when computers where used for two things
too either go to the moon or play pong
and nothing inbetween, you see
and You didn't need a fancy operating system to play pong
and the men who went to the moon, god bless them
did it with no mouse
and a plain text only black and white screen
and thiry-two kilobytes of ram
Beyond that, this guy is lucky its christmas because with multiple 4-9 meg pdf files it would be a silent night for his server.
can't sleep slashdot will eat me
10$ says it's flashing "1202" right about now...
So here's a mirror!!
It's fallen to about € 0.74 to the dollar in the last week; thus about € 2220.
WTMTOHHD.
The higher the technology, the sharper that two-edged sword.
http://opencurve.org/~sunny/misc/slashdot/moon/sta rfish.osfn.org/AGCreplica/
Not to undermine his job, which I think is a major accomplishment, not only by building it but by reimplementing the whole logic from diagrams. But looking at the logic, it seems it could fit easily in a Spartan 3 FPGA. So yes, it could be done cheaper and faster, but not with the degree of detail this guy put on.
Kudos to him
signal_connect(0, "test_top.dut.my_sig", "clk");
$3k + 1.25 man-YEARS of labor... wow.
;)
Even at chinese outsourcing prices, that's one VERY expensive project that doesnt do anything useful.
Go get an Apple ][, you can learn just as much for $50
- Adam L. Beberg - The Cosm Project - http://www.mithral.com/
What a dude does in his own time is hardly topic for debate here. However base and unnatural.
With that kinda money you could rebuild the sound stage they faked the first trip to the moon on!
-bbh
Now he has his own server slashdotted just before [Insert Religous Denomination Holiday Here]. Yup, he sure is the space geek who has EVERYTHING now!
Take that those doing with less!
I give people the moon all the time!! Shall I run for cover?
That would be 131,310 rupees in real money. ;)
There are two reasons why spaceflight computers are relatively underpowered:
Reliability under conditions your PC would fail, like radiation, shock, vibration, acceleration, heat and cold.
Built to solve unique specialized problems for people who are not entirely computer expert.
Navigation computers have to solve complex solid analytic geometry problems for people who are experts in solid analytic geometry but aren't experts in computers and don't have the luxury to spend lots of time to do that.
To be really authentic, he should have made up his own core
memory. Using semiconductor ram is an easy out,
Where on earth are you going to find the vintage IC's for this thing? (Didn't RTFA). In the early 60s, it was either discrete logic using individual transistors and diodes, or really crappy RTL/DTL chips.
When all else fails, run.
In the spirit of giving on this, the holiday season, I present you dictionary.com.
May it serve you well.
Can it simulate the part where the sensor loop queue was overloaded because they forgot to turn off the rendevous radar and the warning lights went crazy and Neil or Buzz wet his suit? (I have no official info that they did, but I bet at least one did but never told anyone.)
Table-ized A.I.
A perfect way to add guidance to my Cruise Missile
LK
"Hi. This is my friend, Jack Shit, and you don't know him." - Lord Kano
Oh right, the dollar is really holding it's own against the Rupee isn't it -7% in 30 days. Please do some research before you try to be cute.
Let's get some PRIORITIES here!
On second thoughts... never mind.
I'm not wrong. You haven't thought about it hard enough.
Time is far, far more precious than money. We only trade *some* of our time for money so we can use that money during the remaining time.
until the late 1970's when the brain trust realized that the whole communication infrastructure could be taken out with a single above ground nuclear blast high in the altitude.
They wire wrapped the board because that was the way things were done in those days.
Now that he's finished the one computer, I imagint he will get going on the Beowulf cluster...
No, not really, these days one can fly to the moon with 10s og millions only, witness the new Indian and Chinese technologies for doing so. Throwing money at the problem as you suggest is the American way my friend.
>>Go get an Apple ][, you can learn just as much for $50 ;)
I disagree. This project completely rules. It's way more than just tinkering around with an Apple ][ -- it's the equivilent of building an Apple ][ from scratch, reverse engineering Applesoft, the monitor, the Sweet 16 emulator, the LISA assembler, building a floppy drive, etc. etc. etc.
Go read the articles and you'll appreciate what a tremendous amount of work this was -- a hell of an achievement of the variety that makes most PhD applications look like a 3rd grade book report.
>>that's one VERY expensive project that doesnt do anything useful.
Yeah? Let's see:
2500 hours of labor -- $125,000
3500 feet of wire -- $345
dog-eared copy of Dr. Dobbs - $5.95
parts -- $3500
Proving you are the ultimate bad-ass King of the Nerds by building a working Apollo 11 Guidance Computer -- priceless.
Awesome work.
I have the utmost respect for the initiative, intelligence, and generosity of the man who built this computer. That said, he didn't build a replica of an Apollo Guidance Computer (AGC). He did not use the same parts, constructing it with higher integration 74LS parts that gave about a 10-to-1 IC package reduction. The original AGC prototype used core memory and his uses static RAM and EPROM. There are countless other differences.
Again, he is deserving of high praise, but he did not replicate the original AGC I prototype. He created a working model which was very true to the original at the block diagram level.
Hmm, they could not use a GUI, since it requires a mouse and everyone knows that the moon is made of cheese, so taking a mouse to the moon would have been a total disaster...
Oh well, what the hell...
"The Intel 80286, a 16-bit processor with a segment-based memory management and protection system. The 80386 added a 32-bit architecture and a paging translation unit, which made it much easier to implement operating systems which used virtual memory." which the linux kernel needs. A few years ago I spent time picking through trash trying to find a 386 so I could try linux. There's some un*x variants that will poke about on Z80 and 6502- but not linux. M$ used to put out Xenix, a un*x that ran on 286s, then sold it to SCO, go figure!
This piqued my interest. Do you have any source info about that?
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Comment removed based on user account deletion
Due to popular demand there are now two mirror sites for the AGC Replica project files:
NASA Office of Logic Design
SpaceRef.com
For ME.
Or perhaps some other geek on your Christmas list.
Even better yet would be a kit, so the recipient would get the fun of assembling the project him<M-Del>themself.
It's too bad all kids nowdays have the attention span of an albino ferret, this'd be a GREAT educational project....
Exceeding the recommended torque is not recommended.
At some point in the distant past (probably in Byte magazine or something) I remember reading advertisements for whitebox systems that featured 80186 processors.
IIRC they were basically faster 8086s.
+++ATH0
This begs the question of how we make voluntary sterilization an attractive option.
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There have been anecdotal stories of astronauts using off-the-shelf laptops aboard the ISS with no issues to speak of.
I'd google, but am on crappy dial-up this evening.
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Yes consumer-grade equipment should work fairly normally *inside* the shielded ISS, but nobody in his right mind would trust the stuff for actual flight control systems.
Its the difference between "aww shucks, there's a speck on my picture" and "retro-rockets failed to fire!"
or even a version that would run in Java on a cell phone??
Not terribly practical I'll admit but pulling out your PDA or even your cell phone and showing an emulated Apollo Guidance Computer might be the epitome of geekdom produced from one's pocket...
Certainly one of these may have been usefull on Apollo 13 as a low power backup computer??
We are too spoiled here in the early 21st century, the apollo computer was high-technolgy of it's era, we now have really cool, fast cpu's and what do we do, we design really bad software to run on them, and the creation of bad designs is pushed over until we have faster cpu's to cover up these really bad design decisions. Remember, electronic calculators were not availible for sale in your local stores when they went to the moon, a lot of calculations were done using slide rules, sure they had mainframes, but you were expected to know how to use a slide rule in engineering and the sciences.
. . .
g 1007_hall_s.ppt
:
0 7.pdf pages 4-5.
This is a link to a a partial tear-down of a Apollo Guidance Computer Logic Unit.
http://klabs.org/mapld04/presentations/session_g/
on slide three, N.B. the cost : $275,800.00.
now i wonder could the guy in the story have afforded to deal with this as well
"In the early orbital missions before Apollo, NASA learned that the human animal, confined in a spacecraft for a week or so, was not as clean as might be expected from observations on Earth. This additional constraint had . . far-reaching impact . . All electrical connections and other surfaces had to be corrosive resistant . . . everything had to be hermetically sealed."
eww!
quote from http://klabs.org/history/history_docs/mit_docs/17
What's the most important thing about what this guy did?
Documentation. He documented every step of the way everything that he did. It's something that's lacking in a lot of geeky projects and it's something that I commend this guy at doing an awesome job at.
My other first post is car post.
"Early gun-type designs are interesting. Because they're so simple, you can (if you like) actually understand the entire critical assembly process, from the start of fission to the propagation of the produced shockwave"
I doubt that we will ever figure out - and I suspect that even if we did figure out we couldn't do much about it
I mean...durpa-durpa-durrrrr....
Blar.
This guy is awesome. Total geekness and I love it. I tip my hat to people like this as they are people whom really attempt to understand the inner workings of computers and technology. Great job!
Valkyrie is about to die! Wizard needs food -- badly!
I suggest you go to www.oanda.com and look at the official exchange rate for the rupee as of Dec. 24 before you attempt to demonstrate exactly how much of an asshat you are.
plus astronauts would have one sucky time flying the craft by hand to the moon.
For the most part, what the astronauts did was closer to "flying the craft by hand" then the kind of auto-pilot we think of today.
The computers for apollo did pretty straightforward stuff, and were mainly there so the astronauts didn't have to keep doing stuff non-stop. They could still sight stars and calculate there path and manual fire rockets to adjust (like they did in Apollo 13),
The computer did relieve the crew of having to do lots of calculations which allowed them to focus on control of the craft, but some things were done manually - despite the fact that the computer could have done it automatically.
In a transcript (typos in original) of David Scott's remarks, from The Apollo Guidance Computer: A User's View there is an interesting discussion of the auto-pilot capability of the AGC, and then he goes on to say:
"The lunar landing itself could have been done automatically and many times people ask me about that. Could it have been accomplished automatically through the LEM guidance computer? Nobody ever did it. We all felt that when you get that point and you are ging to land on the moon, you have to have your hands on the stick. I like computers and I believe in computers, but it aint going to land me on the moon. I'm going to do that. If something gets screwed up then it is going to me, it isn't going to be the computer. Actually, my thinking at the time was that if a problem did occur it was so time critical that you wouldn't have time take corrective action, so you stay ahead of that problem by flying it manually."
can anyone give a compelling reason why keeping the poor from reproducing is a bad idea?
Note that this is not a eugenics program.
+++ATH0
Need I say more?
"You lied to me! There is a Swansea!"
From the first report-
Logic Design
The original AGC4 was built almost entirely from 1964-era 3-input NOR gate ICs; about
5,000 of them. Original gate-level logic designs are not available.
So they were right - we DID loose the plans for the original Apollo!
"You lied to me! There is a Swansea!"