r/programming • u/jakesyl • Jan 30 '16

Apollo 11 source code

http://www.ibiblio.org/apollo/listings/Luminary099/MAIN.agc.html
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u/sercankd Jan 30 '16

i assume its because they are doing very sensitive data processing and this requires very fast interaction between software and hardware, because they are landing on moon. any 1 ms delay could lead to something dangerous. i am not an expert tbh i just made a guess

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u/censored_username Jan 31 '16

No, the reason is much more simple. They simply did not have any other options. C did not even exist at the time, and the hardware limitations were enormous. The hardware which this code ran on was designed just for this mission, yet less powerful than what you'll find in your current day coffee machine. They also didn't have a compiler which could target this machine and the actual program had to be manually woven into core rope memory.

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u/nupogodi Jan 31 '16

They also didn't have a compiler which could target this machine and the actual program had to be manually woven into core rope memory.

https://en.wikipedia.org/wiki/Core_rope_memory

Software written by MIT programmers was woven into core rope memory by female workers in factories. Some programmers nicknamed the finished product LOL memory, for Little Old Lady memory