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Apollo 11 Guidance Computer source code

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101–110 of 150 posts

Re: Apollo 11 Guidance Computer source code

#101

It's amazing that this is all online now, and easy to browse. Lots of source here too http://www.ibiblio.org/apollo/links.html FWIW, I did performance analysis of the guidance computer and the 1202 and 1201 alarms at the start of my ACM Applicative 2016 keynote: https://youtu.be/eO94l0aGLCA?t=4m38s

hey there Brendan, thats a pretty awesome presentation (I m only 20 minutes into the talk as of now ).. But you mention that the Apollo Engineers expected the CPU load to be about 85% during descent. And the Guidance computer's Kernel ran "Dummy Jobs" when no real jobs were run.

What are these Dummy Jobs ? And Why did they have to do this instead of just leaving the CPU idle ?

Re: Apollo 11 Guidance Computer source code

#102
post #15

Other than gaining satisfaction from the historical importance of this code is there any conceivable way we can get some use of it - like try it out. Even setting that aside, what is it I'm looking at? Assembly?

> is there any conceivable way we can get some use of it I wonder whether there's any way of getting it into one of the autopilots for Kerbal Space Program.

https://news.ycombinator.com/item?id=12051150

Re: Apollo 11 Guidance Computer source code

#103

It's amazing that this is all online now, and easy to browse. Lots of source here too http://www.ibiblio.org/apollo/links.html FWIW, I did performance analysis of the guidance computer and the 1202 and 1201 alarms at the start of my ACM Applicative 2016 keynote: https://youtu.be/eO94l0aGLCA?t=4m38s

hey there Brendan, thats a pretty awesome presentation (I m only 20 minutes into the talk as of now ).. But you mention that the Apollo Engineers expected the CPU load to be about 85% during descent. And the Guidance computer's Kernel ran "Dummy Jobs" when no real jobs were run. What are these Dummy Jobs ? And Why did they have to do this instead of just leaving the CPU idle ?

> Why did they have to do this instead of just leaving the CPU idle ?

This would require a CPU that was designed to idle.

Re: Apollo 11 Guidance Computer source code

#104

Earlier quoted context omitted.

I really wish we can do an AMA with these two, > # THE MASTER IGNITION ROUTINE WAS CONCEIVED AND EXECUTED, AND (NOTA BENE) IS MAINTAINED BY ADLER AND EYLES. I had to look this up, NOTA BENE is latin for, observe carefully or take special notice

I think I'm going to start using NOTA BENE in my source code comments just to be fancy. [EDIT] On second thought "HONI SOIT QUI MAL Y PENSE" would be much better ("Shame on whosoever would think badly of it")

Postgres' code is full of NB: :)

Re: Apollo 11 Guidance Computer source code

#105

Earlier quoted context omitted.

hey there Brendan, thats a pretty awesome presentation (I m only 20 minutes into the talk as of now ).. But you mention that the Apollo Engineers expected the CPU load to be about 85% during descent. And the Guidance computer's Kernel ran "Dummy Jobs" when no real jobs were run. What are these Dummy Jobs ? And Why did they have to do this instead of just leaving the CPU idle ?

> Why did they have to do this instead of just leaving the CPU idle ? This would require a CPU that was designed to idle.

wow , wow ! Looks like I don't understand the first thing about the CPU design . Do CPUs have to be designed to IDLE ? Can you throw some more light on this ?

Re: Apollo 11 Guidance Computer source code

#107

BURN_BABY_BURN--MASTER_IGNITION_ROUTINE.s - https://github.com/chrislgarry/Apollo-11/blob/dc4ea6735c4646...

I really wish we can do an AMA with these two, > # THE MASTER IGNITION ROUTINE WAS CONCEIVED AND EXECUTED, AND (NOTA BENE) IS MAINTAINED BY ADLER AND EYLES. I had to look this up, NOTA BENE is latin for, observe carefully or take special notice

NB. Is how you indicate a comment in J.

Re: Apollo 11 Guidance Computer source code

#108
post #3

Love this line: TC BANKCALL # TEMPORARY, I HOPE HOPE HOPE CADR STOPRATE # TEMPORARY, I HOPE HOPE HOPE TC DOWNFLAG # PERMIT X-AXIS OVERRIDE https://github.com/chrislgarry/Apollo-11/blob/master/LUNAR_L...

Typical temporary code, which 46 years later is still there.

Whenever I put in temporary code like that, I always leave my full name, the date, and a snarky comment about "suuuuuure this is temporary". Seriously.

Re: Apollo 11 Guidance Computer source code

#109
post #88

There's a simulator, if you want to run it.[1] But it's just a simulator for the computer; there's no spacecraft attached. There's a mod for Kerbal Space Program which gives it real solar system planets and dimensions. (KSP's world is way undersized so things happen faster.)[2] There's another mod for Kerbal Space Program to give it real dynamics.[3] (KSP doesn't really do dynamics right; the spacecraft is under the…

I'm really surprised there isn't a moon landing simulator based on the real code yet.

There's an Orbiter plugin[1] that simulates the rest of the spacecraft. IIRC it can interface with this simulator to get an accurate simulation of the computer.

[1] http://nassp.sourceforge.net/wiki/Main_Page

Re: Apollo 11 Guidance Computer source code

#110

BURN_BABY_BURN--MASTER_IGNITION_ROUTINE.s - https://github.com/chrislgarry/Apollo-11/blob/dc4ea6735c4646...

I really wish we can do an AMA with these two, > # THE MASTER IGNITION ROUTINE WAS CONCEIVED AND EXECUTED, AND (NOTA BENE) IS MAINTAINED BY ADLER AND EYLES. I had to look this up, NOTA BENE is latin for, observe carefully or take special notice

Maybe you will find this article interesting:

Don Eyles Walks Us Through the Lunar Module Source Code

http://hackaday.com/2016/07/05/don-eyles-walks-us-through-th...

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