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widosm
2002-Jun-09, 10:15 PM
I was reading JayUtah's post (CosmicDaves 32 Questions) regarding AGC code, and in my desperate impatience to see some, did some Google work. I drummed up the following link:
http://verdade.no.sapo.pt/moon/landing_hoax.html
Lists some info regarding the AGC, and also has a (rather scruffy) Jpeg of a tiny portion of code. This appears to be part of a larger hoax site I've not seen before, and discusses other conspirasist (sp?) theories. Unfortunately I cant find a way back to a 'main' page /phpBB/images/smiles/icon_frown.gif

Jay, please post any code you can! If anyone else has more info regarding the computer systems used, please post here also...

Cheers,
widoxm

Alan G. Archer
2002-Jun-09, 11:53 PM
From Dr. Dobb's Journal: "One Giant Leap: The Apollo Guidance Computer (http://www.ddj.com/documents/s=1494/ddj0006hc/)." Also, the AGC source code listing (http://www.ddj.com/documents/s=1494/ddj0006hc/0101hc001f1.htm).

A less scruffy JPEG sample of AGC source code (http://klabs.org/richcontent/Misc_Content/AGC_And_History/luminary1.jpg), courtesy of Gary Neff.

More on Gary Neff (http://www.hq.nasa.gov/alsj/garyneff.html) from NASA's Apollo Lunar Surface Journal (http://www.hq.nasa.gov/alsj/). Gary claims to have the complete source code for Luminary and Colossus (http://www.hq.nasa.gov/office/pao/History/computers/Ch2-6.html), the two major lunar flight programs.

"The moon landing hoax - Computing technology (http://verdade.no.sapo.pt/moon/landing_hoax.html)" is the busy work of a small mind.

<font size=-1>[ This Message was edited by: Alan G. Archer on 2002-06-09 20:39 ]</font>

JayUtah
2002-Jun-09, 11:55 PM
I know Gary Neff, and he's legit. The page quoted is from Luminary, while I have the entire source listing from Colossus. The hardware was the same for both spacecraft, but the software was obviously different for each spacecraft.

NASA didn't develop the code. It was developed by the Charles Stark Draper lab and MIT. It is absolutely untrue that the software was undocumented. In fact, it is probably the most heavily documented chunk of code in the industry. Hundreds, if not thousands, of pages of papers, diagrams, and other supporting information was produced by the Draper lab in support of the programming.

Other charges made on this site:

The answer is not easy to find. Actually NASA apparently doesn't care about the key piece of evidence - the software source code.

NASA didn't write it, NASA never owned it, and NASA isn't responsible for providing it. MIT, however, will provide it on demand. Almost all serious NASA historians know how and where the code was written.

If you have a minimal knowledge of hardware and software and afterwards you still believe in the moon landing hoax, the most probable reason is that you are ULTIMATE LIE technique.

Or perhaps it takes more than a minimal knowledge of these things, and a bit of history. It's amazing how many people who have plugged a video card into their computer and immediately believe they know everything about every kind of computer ever invented.

4000 discrete integrated circuits from Fairchild Semiconductor

Try 5,600. Philco also provided ICs to the project.

Disk: None

Most embedded systems don't have disks. It only runs one program, and you put the program in ROM.

project not developed according to software life cycle principles

Red herring. That's like saying, "Henry Ford's original assembly line wasn't operated by robots, therefore it wouldn't have been possible for him to produce an automobile."

one year before the moon landing there were 400 people working on it - no wonder NASA does not tell you if they were, at that point, specifying, implementing or testing

Since NASA wasn't developing the software, it would have been fruitless to ask them.

The software development effort began in 1962 using software emulation to test execution. This emulator evolved into a faithful bitwise replica of the final execution environment.

The operating system came first, then the interpreter, then the core software, and then the mission-specific modifications.

The MIT library is jam packed with materials having to do with the Apollo computers. Many of the principal researchers, e.g., Eldon Hall, have written and spoken extensively on the AGC. Further, the AGC served as the example of fly-by-wire for future applications.

The assertion that the AGC was developed in some shroud of secrecy from which nothing has survived is pure crap. It's simply the argument of people who haven't looked very hard (in the wrong place), found nothing, and tried to make something out of that.


<font size=-1>[ This Message was edited by: JayUtah on 2002-06-09 20:10 ]</font>

JayUtah
2002-Jun-10, 12:02 AM
MIT's instrumentation lab also runs a site devoted to documentation of the AGC. I've temporarily lost the URL, but I'm sure someone else has seen it.

JayUtah
2002-Jun-10, 12:17 AM
Ooh, looky what I found. This is an excellent summary of the digital autopilot code.

http://www.mathworks.com/company/newsletter/sum99/lunar_module.shtml

Alan G. Archer
2002-Jun-10, 12:34 AM
On 2002-06-09 20:02, JayUtah wrote:
MIT's instrumentation lab also runs a site devoted to documentation of the AGC. I've temporarily lost the URL, but I'm sure someone else has seen it.


Some MIT links:

"Apollo Guidance Computer Documents and Other Resources (http://hrst.mit.edu/hrs/apollo/public/documents.htm)"

"An Introduction to the Apollo Guidance Computer and the AGC project (http://hrst.mit.edu/hrs/apollo/public/introduction.htm)"

"Project History: Apollo Guidance Computer (http://web.mit.edu/6.933/www/apollo.html)"

JayUtah
2002-Jun-10, 12:45 AM
Follow the first link and then go to the "Documents" section and select a link. That will take you to a very large repository of original AGC materials. That's the AGC repository I was thinking of; thanks for finding the link. MIT has promised to add to this periodically. It looks about the same as the last time I was there.

David Hall
2002-Jun-10, 04:33 AM
On 2002-06-09 18:15, widoxm wrote:

This appears to be part of a larger hoax site I've not seen before, and discusses other conspirasist (sp?) theories. Unfortunately I cant find a way back to a 'main' page /phpBB/images/smiles/icon_frown.gif


I flipped all through the site, and you're right. There doesn't seem to be any main page. Or any order whatsoever. It's just a complete mish-mash of confusing and rambling conspiracy ideas. The OKC bombing, Elan, Serbia, Creationism, RFK, Masons, etc. All without any central theme or focus.

My guess is that this site is organized in just about the same way the author's mind is organized: not at all. It's an incoherent railing against everything.

Geo3gh
2002-Jun-10, 05:08 AM
On 2002-06-09 19:55, JayUtah wrote:
The assertion that the AGC was developed in some shroud of secrecy from which nothing has survived is pure crap. It's simply the argument of people who haven't looked very hard (in the wrong place), found nothing, and tried to make something out of that.


And for me this is the most frustrating part of arguing with HBs (or any other flavor of CT for that matter). How any moderately educated person can accept ignorance as data is beyond me. Especially when people like Jay can find this stuff on the web in picoseconds (ok, a minor hyperbole, but you know what I mean).

2002-Jun-10, 10:29 AM
2:22 A.M. "PST"
used a noun + verb syntax. Entry example : DISPLAY + VELOCITY
Size: AGC - 24" x 12.5" x 6" (HWD); DSKY - 8" x 8" x 7" (HWD)
---------------
NOT following this D`bait well
as far as I know ? and i don't
it mostly depends upon the central
processer [CPU]
the manufacturer {and the secrecry around that}
my guess would be it was Hi.
and their4: any CODE i get
would be D`coy D.cod 2:26 A.M. PST

JayUtah
2002-Jun-10, 02:47 PM
How any moderately educated person can accept ignorance as data is beyond me.

Exactly. "We couldn't find any X?" or "There is no evidence of X?" is the lamest argument one can possibly deploy, unless one is prepared to give evidence of an appropriately exhaustive search including interviews with the top historians and experts on the subject of X.

Especially when people like Jay can find this stuff on the web in picoseconds

To be fair, most of my AGC information is not from the web. I happen to know where a lot of it can be found on the web, but that's not because I got my information there. One of my professors in graduate school quite proudly sported an actual Apollo AGC DSKY on his very cluttered office shelf. Not one that actually few, sadly, but one that was used in the Apollo 14 software acceptance testing. So most of my information comes from him and from sources to which he has since pointed me.

The software was written at MIT, with Apollo computer experts in residence. It's actually a funny story -- MIT hackers meet NASA "suits". So it makes sense that if you want to learn about what made the AGC tick, you ask MIT. If you want to know how it was built, you ask Raytheon.

I strongly doubt any of these conspiracy theorists have actually done due diligence in their research. For most of these fields there are recognized experts. Eldon Hall, for example, writes and lectures on the AGC. Why doesn't his expertise appear in any conspiracist materials? Why do the conspiracists always rely on their own pretended expertise?

The answer, of course, is that the truth is the last thing they're after. They don't want to know the facts as they really are, but only the facts they can spin to support the conclusion they've already decided upon.

Personally I think it's amusing that the only "facts" Cosmic Dave has given regarding the AGC are wrong. He certainly must have done a lot of "research".

pvtpylot
2002-Jun-10, 03:12 PM
On 2002-06-10 10:47, JayUtah wrote:
I strongly doubt any of these conspiracy theorists have actually done due diligence in their research. For most of these fields there are recognized experts. Eldon Hall, for example, writes and lectures on the AGC. Why doesn't his expertise appear in any conspiracist materials? Why do the conspiracists always rely on their own pretended expertise?


Their answer, of course, is that experts like Mr. Hall were obviously in on the conspiracy and therefor can't be trusted. Conveniently, in their minds this allows them to dismiss any expert disputing their claims out of hand, without the need to examine any evidence but their own. They consider non-government skeptics like us to be sheep in the evil government's grand conspiracy. Hence cd's little "baa" remarks at the end of one of his posts in another thread. Sadly, I think what these people really need is a psychology guru rather than an authority on Apollo.

JayUtah
2002-Jun-10, 03:31 PM
They consider non-government skeptics like us to be sheep in the evil government's grand conspiracy.

If we were just going along with the propositions and not questioning them, we'd be sheep. But since we question the propositions, the alternative propositions, and frequently each other along the way, it's hard to argue that we're the complacent unquestioning type.

Cosmic Dave, on the other hand, defers to his authors on just about every question. That's a pretty strong indicator he just bought into their philosophy without doing any intellectual work on his own. Can't you just see Bennett and Percy with shepherd's crooks in their hands, and Dave Cosnette with a bell around his neck eating out of their hands?

I don't have to be told what my opinion is. I've formed it according to my own research and expertise.

pvtpylot
2002-Jun-10, 04:05 PM
On 2002-06-10 11:31, JayUtah wrote:
Cosmic Dave, on the other hand, defers to his authors on just about every question. That's a pretty strong indicator he just bought into their philosophy without doing any intellectual work on his own. Can't you just see Bennett and Percy with shepherd's crooks in their hands, and Dave Cosnette with a bell around his neck eating out of their hands?


Interesting visual. Of course, most herd animals tend to display more loyalty to their flock than cd does. How many times have we seen him try to disassociate himself from his source when their claims are shown to be faulty?

sts60
2002-Jun-10, 04:30 PM
I've noticed that the DDJ article cited earlier makes the, evidently incorrect, "no documentation other than the source" claim. Also, the DDJ image of the source listing says "by NASA", although we know this meant the client rather than the developer.

Why do I bring up such trivial points? Because this is the kind of trivia the HBs use in their "wall of noise" approach to distorting reality.

I expect both of these trivia-bits to be thrown up as examples of Jay being "wrong". Not that I expect c-dave or any other HB to actually put forth the effort to go look at the sites, but rather they'll just see this post and go to town.

I suppose this is like giving them ammunition, but after all these are guys who absolutely cannot hit anything other than their own feet.. I'm thinking Elmer Fudd here.

"The busy work of a small mind." I like that. Alan, may I use that (with attribution, of course)?

Geo3gh
2002-Jun-10, 04:44 PM
On 2002-06-10 10:47, JayUtah wrote:
Especially when people like Jay can find this stuff on the web in picoseconds

To be fair, most of my AGC information is not from the web.

But I include in this not just the AGC stuff, but photos that can be found in the surface journal, video footage, etc.

But also telling is that we as a group can generally tell you where we found it, and why we think it's reliable.

Jay, your explanations of where you did and didn't get your data just reinforces my impression that you know just a bit of what you're talking about.