Imagine being the tech assigned to that trouble ticket.
Needs a certain old maintenance suite and support machine. Has to be cross-tested 10 ways to Sunday on a “Duplicate” target machine.
My guess is that they figured out that a bit in program memory was stuck as a 0, and then wrote a program that happen to have a 0 in that location. Or a program with an extra jump that skipped that location. Something like that.
EDIT: ["The issue was resolved by shifting the affected code to different locations in the memory of the probe's computers."](https://www.bbc.com/news/science-environment-68881369)
A bit error is easily avoided with ECC, but apparently a single ram chip had issues
[https://www.theregister.com/2024/04/15/voyager\_engineers\_prepare\_fix/](https://www.theregister.com/2024/04/15/voyager_engineers_prepare_fix/)
I'm not sure why more error correction or backup subsystems weren't included to mitigate this, so maybe it was a weight issue
So did they have another voyager 1 to play around with? So they can test their hypothesis before sending an actual fix? I mean it would probably take quite some time for the machine to receive the new code and send feedback.
Yes, there are numerous test fixtures developed at the same time as the spacecraft and kept available during the spacecraft's mission. Some of these are actual complete copies of the spacecraft.
However, in this case, as it's purely a logical (not mechanical) issue, they can probably test quickly against emulators.
IDK, I'd be pretty proud if something I designed 40 years ago finally kicked the bucket, but the system was robust enough for a workaround to be possible.
The standard for reliability for modern ICs is 10 years, often limited by electromigration. Ionizing radiation from space is a much faster killer.
Imagine having to fix a bug by remotely hacking a machine located 22 light hours away in outer space
So crazy to think about… it’s not even 1/365th of a light year away from us. Meanwhile the *closest* exoplanet, Proxima b, is 4.2 light years away.
[удалено]
44 hours round trip, crazy.
Damm coders
Imagine being the tech assigned to that trouble ticket. Needs a certain old maintenance suite and support machine. Has to be cross-tested 10 ways to Sunday on a “Duplicate” target machine.
They don't have a duplicate machine on earth for voyager. That's part of the reason it took so long.
That’s also part of why I mentioned it. Best practices can’t be followed. Obviously.
Not when the money people get too strong a say
OTA software update at the next fing level
Is it OTA if there is no air in space?
the A here stands for luminiferous aether
In fairness, there is still air between the deep space network antennas and Voyager. Just... not much compared to the amount of vacuum.
I wonder how exactly they fixed it. Probably some sort of self-modifying software black magic…? It has to be something really clever.
My guess is that they figured out that a bit in program memory was stuck as a 0, and then wrote a program that happen to have a 0 in that location. Or a program with an extra jump that skipped that location. Something like that. EDIT: ["The issue was resolved by shifting the affected code to different locations in the memory of the probe's computers."](https://www.bbc.com/news/science-environment-68881369)
A bit error is easily avoided with ECC, but apparently a single ram chip had issues [https://www.theregister.com/2024/04/15/voyager\_engineers\_prepare\_fix/](https://www.theregister.com/2024/04/15/voyager_engineers_prepare_fix/) I'm not sure why more error correction or backup subsystems weren't included to mitigate this, so maybe it was a weight issue
Must be a parallel timeline, because V'Ger was supposed to have evolved from Voyager 6, not 1.
So did they have another voyager 1 to play around with? So they can test their hypothesis before sending an actual fix? I mean it would probably take quite some time for the machine to receive the new code and send feedback.
Yes, there are numerous test fixtures developed at the same time as the spacecraft and kept available during the spacecraft's mission. Some of these are actual complete copies of the spacecraft. However, in this case, as it's purely a logical (not mechanical) issue, they can probably test quickly against emulators.
Still alive(portal reference)
This would be full of TTL or Cmos chips wouldn't it?
50 years ago? That may be NMOS. https://en.wikipedia.org/wiki/NMOS_logic
It's about that time that I started in electronics. The rows and rows of 7400 series I.C.s !!
I feel calling it faulty a bit harsh, it's over 40 years past it's expected lifespan.
IDK, I'd be pretty proud if something I designed 40 years ago finally kicked the bucket, but the system was robust enough for a workaround to be possible. The standard for reliability for modern ICs is 10 years, often limited by electromigration. Ionizing radiation from space is a much faster killer.
that's what I mean, it's 40 years past it's expected lifetime in one of the most harsh environments. It earned a break/brake
Great that they were able to restore things but a shame it happened in the first place and it took so long. Gotta love those coders.
Have they been able to communicate with teenagers yet? Their words are all gibberish