Anyone who is looking for something to run it on could take a look at <i>Block I Apollo Guidance Computer (AGC): How to build one in your basement</i> [1]. The build took one guy four years and a <i>lot</i> of wire-wrap. A fascinating and quite awe-inspiring piece of work.<p>[1] <a href="http://klabs.org/history/build_agc/" rel="nofollow">http://klabs.org/history/build_agc/</a>
This is a blog linking to a blog linking to the source (from 2009).<p><a href="http://googlecode.blogspot.com/2009/07/apollo-11-missions-40th-anniversary-one.html" rel="nofollow">http://googlecode.blogspot.com/2009/07/apollo-11-missions-40...</a>
It's worth noting that the software, while only 36k machine words long, and the hardware, which was very slow even by the standards of other computers of the 60s, were remarkable works created in only a couple years by huge teams (peak of 800 people working on hardware and 400 on software IIRC).<p>Its popular to dismiss the AGC as simple and uninteresting, but it was a challenging engineering task, and it never once had a failure in flight.<p>There's lots of resources on the internet to read more. A great book on the topic is Digital Apollo by David Mindell
If this kind of thing interests you, there are some great resources here about the Gemini and Apollo guidance computer architecture, including recreations of them: <a href="http://www.ibiblio.org/apollo/" rel="nofollow">http://www.ibiblio.org/apollo/</a>. I also recommend the book "Digital Apollo" about the role of digital computers in early space flight. I found both fascinating.
<a href="https://code.google.com/p/virtualagc/source/browse/trunk/Luminary099/LUNAR_LANDING_GUIDANCE_EQUATIONS.agc#180" rel="nofollow">https://code.google.com/p/virtualagc/source/browse/trunk/Lum...</a><p>That article calls out this line (among others). I wonder what the actual story behind this comment was. I'm sure it's not as bad as, "I'm just putting this in temporarily and we should fix it before it goes to Mars". It probably means something else.<p>Anyone have any idea?
We invest a lot of code in GUI, which makes me think of:<p><i>I'm afraid the holodeck will be society's last invention. - Scott Adams</i><p>And this ultimate GUI would require the ultimate coding effort.
<a href="http://code.google.com/p/virtualagc/source/browse/trunk/LICENSE.txt" rel="nofollow">http://code.google.com/p/virtualagc/source/browse/trunk/LICE...</a><p>"The software for the Apollo Guidance Computer (AGC) and LM Abort
Guidance Computer (AGS) is believed to be in the public domain."<p>Eh? So is it open source or not?<p>I doubt someone would come around and claim exclusive copyright on this, but still... Netlib had the same problem, and that's why replacements exist. The ACM still once in a while claims copyright on ancient Fortran code from the late 1960's. Back then it was a blissful golden era when people didn't even think that source code was elligible for copyright.
Given the pocket calculator joke[1] I'm wondering if anyone has built functionally equivalent AGC code on a more modern processor? And by functionally equivalent I mean a black box tester with an Apollo AGC would not be able to tell if it was running the old code or the new code.<p>[1] <i>"It’s been famously remarked that the on-board systems in Apollo 11 had less computing power than a modern pocket calculator."</i> -- <a href="http://apcmag.com/apollo-11-code-goes-open-source.htm" rel="nofollow">http://apcmag.com/apollo-11-code-goes-open-source.htm</a>
Yes it's a 2009 blog post, but I still found it new and interesting.<p>Especially the "# TEMPORARY, I HOPE HOPE HOPE" comments, so I decided to look into them and hopefully find someone who has a clue to explain...which I did, here's a link for anyone else interested...<p>(last comment) <a href="http://www.metafilter.com/83450/Apollo-11-Source-Code" rel="nofollow">http://www.metafilter.com/83450/Apollo-11-Source-Code</a>
Trashy Little Subroutines is going to be my new band's name.<p><a href="https://code.google.com/p/virtualagc/source/browse/trunk/Luminary099/LUNAR_LANDING_GUIDANCE_EQUATIONS.s?r=258#1375" rel="nofollow">https://code.google.com/p/virtualagc/source/browse/trunk/Lum...</a>
So they must have written this simulator without help from source code <a href="http://svtsim.com/moonjs/agc.html" rel="nofollow">http://svtsim.com/moonjs/agc.html</a>. While it doesn't strike me as a bad simulator, I wonder if it's right.
Google Code? That still a thing? It must be enterprise-government-class contracts like this keeping it alive.<p>It would have been much cooler to see it on Github and people forking away at it.