[meteorite-list] Mars Rover Spirit Restored to Health

From: MexicoDoug_at_aol.com <MexicoDoug_at_meteoritecentral.com>
Date: Thu Apr 22 10:31:20 2004
Message-ID: <2098C5BC.5140F62D.0BFED528_at_aol.com>

Thanks for the kind and informative answers in this and the other post, Ron ... At only 128 MB, that sounds surprisingly low ... it's pretty standard on a decent digital camera nowadays (and costs $100 or less, though I guess you have to keep it warm), that many dealers are sporting in Tucson. Also I can add that I recall reading, -don't remember where- that the data transfer rate (e.g., upload and download) for the communication netork / Rover is only around 11 Kbits per second ... if true, that's about one third the rate of a conventional land phone line (read one third of a dial up conection)... so maybe the memory isn't needed (128MB would take very near one Sol to transfer continuously assuming that were possible).

Given the size of Flash Memory, I guess next time there could be an automatic backup safety parallel system that is activated by an independent signal. I.e. a reboot using a simple safety mode. Also, had the programming been in a lower level language, I wonder if the software crash would have been as likely to occur. But this is easy to sit back and contemplate now:)

Saludos, Doug "Tucson" Dawn



In a message dated 2/3/2004 9:02:21 PM Eastern Standard Time, baalke_at_zagami.jpl.nasa.gov writes:

>
>
> >
> > What type of operating system or machine language environment is being used?
> > How many megabytes is the total flash memory's capacity?
>
> The operating system is VxWorks, a real-time Unix operating system. It was
> also used on the Sojourner rover. I've programmed on VxWorks before, and it
> is a nice operating system, though I admit I have a Unix
> bias. Most of the
> rover's software is in C. The flash memory is 128 MB.
>
> Ron Baalke
Received on Wed 04 Feb 2004 03:27:29 AM PST