Preforming A Remote Firmware Upgrade 350 Million Miles Away - Page 1
Forum section: electronics / general

author: Sionyn
author_rank: Frequent Contributor
timestamp: August 13, 2012, 09:39:18 pm
content: Wonder what the disaster recover routine ishttps://www.computerworld.com/s/article/9230151/NASA_upgrades_Mars_Curiosity_software_..._from_350M_miles_away

author: bullet308
author_rank: Frequent Contributor
timestamp: August 13, 2012, 10:03:30 pm
content: Usually, there is a countdown timer that has to be reset periodically. If that timer hits zero, it loads a default piece of software that puts it in a mode where it tries different ways of phoning home.

author: tom66
author_rank: Super Contributor
timestamp: August 13, 2012, 10:49:00 pm
content: They have a backup computer - but frankly, with a $2bn project, where's the BACKUP of that??

author: FenderBender
author_rank: Super Contributor
timestamp: August 14, 2012, 01:37:20 am
content: I don't know man. Those boards probably have like 10mm of conformal coating on them and are made with like 300*C parts. Nearly indestructible! Minus tin wiskers...damnit RoHS

author: Psi
author_rank: Super Contributor
timestamp: August 14, 2012, 01:43:46 am
content: I thought NASAs was still using lead solder for that very reason.And yeah, there will be lots of watchdogs and auto recovery modes, probably all stored in ROM.Or, if not ROM, at least stored in a special chip with mechanical locking of the WRITE pin.

author: RCMR
author_rank: Frequent Contributor
timestamp: August 14, 2012, 03:17:14 am
content: I read a really interesting article on the computers they use in that rover.Apparently they're only about 200MHz clock-speed and have trifling amounts of computational power but they are *really* hardened against radiation that would bit-flip a regular CPU to death in no-time flat, once it was out of earth's protective magnetosphere.I guess they also X-ray, heat-cycle and age the processors so to get them to the best point on the "probability of failure" bell curve before they use them too.It's much better to have a slow processor that works than a fast-one that doesn't I guess.

author: SeanB
author_rank: Super Contributor
timestamp: August 14, 2012, 04:42:06 am
content: 2 computers, a watchdog on each and a dead mans switch to recover if both go oops. Plus a simple method of updating, send twice, store in RAM and then compare the 2 copies. If same then flash a block in the non used unit, then send a copy of the block back for verification. Rinse and repeat until all blocks done, then swap to the other unit and have the same done to the primary, which now becomes the backup.Hopefully NASA learned from Hubble where they had a backup processor board that was only tested when the primary failed, and had not been powered for 14 years until it was needed.

author: Bored@Work
author_rank: Super Contributor
timestamp: August 14, 2012, 04:54:16 am
content: Quote from: RCMR on August 14, 2012, 03:17:14 amI keep telling that my wife when she complains I work too slowly through the HONEYDO list ...

author: Mechatrommer
author_rank: Super Contributor
timestamp: August 14, 2012, 11:06:35 am
content: Quote from: RCMR on August 14, 2012, 03:17:14 ambut it's much better to have a fast processor that works.

author: Mechatrommer
author_rank: Super Contributor
timestamp: August 14, 2012, 11:30:58 am
content: Quoteduh. why dont they use Windows and only upload the new install, ask Windows to load new install and unload the old one without reboot? how uncivilized.

author: danntor
author_rank: Contributor
timestamp: August 14, 2012, 12:51:41 pm
content: If it fails do they have a remote pin shorter?