Apollo 11 vs. USB-C Chargers (2020)

Re:Apollo 11 vs. USB-C Chargers (2020) by dikei on Tuesday December 26, 2023 @11:24PM (#38779080)

It's more complicated than that, in the link, they described it better:

>> The microcontrollers, running on PowerPC processors, received three commands from the three flight strings. They act as a judge to choose the correct course of actions. If all three strings are in agreement the microcontroller executes the command, but if 1 of the 3 is bad, it will go with the strings that have previously been correct.

This is a variation of Byzantine Tolerant Concensus, with a tie-braker to guarantee progress in case of absent voter.

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Re:Apollo 11 vs. USB-C Chargers (2020) by mcbutterbunz on Tuesday December 26, 2023 @11:45PM (#38779171)

I’m curious how often the strings are not in agreement. Is this a very rare occurrence or does it happen often?

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Re:Apollo 11 vs. USB-C Chargers (2020) by denton-scratch on Wednesday December 27, 2023 @10:17AM (#38782771)

> Byzantine Tolerant Concensus

I was taken to task for mis-spelling "consensus"; I used to spell it with two 'c's and two 's's, like you. It was explained to me that it's from the same root as "consent", and that's how I remember the right spelling now.

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Re:Apollo 11 vs. USB-C Chargers (2020) by dikei on Thursday December 28, 2023 @02:13AM (#38790883)

Good point.

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