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Comment by usr1106 | Hacker News Reader

Those systems are older than the 6502, so they must be extremely simple seen from today's complexity. Amazing what one can achieve without complexity. How much technology today gets wasted for no good, like e.g. serving ads.

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They are older, but you have to remember that the 6502 was a low-cost CPU used in home computers, so the hardware on board Voyager is likely a bit more advanced. And it's also worth remembering that an even older computer guided the Apollo capsules to the Moon and back safely...

If you want a programmer's eye view of the Apollo hardware / software, I recommend Sunburst and Luminary: an Apollo Memoir by Don Eyles. He wrote some of the programmes that landed the Lunar Module and gives a great perspective on how they worked and integrated with the other programmes (like the radar manager) also running on the LM computer and competing for the tiny computational resources available.

[Edit] Including how on one mission he developed a software hack that an astronaut had to type in, correctly, or else, in the few minutes between the LM emerging from the lunar far side and reaching the point where a landing burn was initiated.

I am just reading it now and it is better than anticipated.

According to Wikipedia, there are actually numerous 16 and 18 bit computers on-board (none of which are µP/MCUs, of course), with around 64K memory and 64MB of tape storage. The data link has a maximum speed of 115 kbps.

https://en.wikipedia.org/wiki/Voyager_program#Computers_and_...

115kbps while it was out as far as Jupiter, and falling off with distance. I can think of a few places where a solid 115kbps would be more than adequate right here on Earth.

Consider that this is in the same band as broadcast satellite TV but with a fraction of the power of for example the Astra 2 satellites. Think in terms of looking out for the brake light of a motorbike in orbit around Jupiter ;-)

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