MER Spirt malfunctioning

[cjolley]

On the language thing:
C is what they should use.
It compiles pretty close to what it would have been in asm.
And, if written correctly, it's as easy to read as anything else.

I am fixing to throw out my copy of Merridian Ada this weekend to make room in a book case.
It's old, but if anyone's interested let me know. It is about 8 disketts and a huge manual in a huge binder.
DOS based, of course.

[Jon P. Inghram]

Cool, found a site that has pretty good transcripts of the briefings: http://spaceflightnow.com/mars/mera/status.html

[gt40]

Nice site Jon.

[Jon P. Inghram]

I think SNAFU is a good acronym for it's current condition:

NASA's Spirit rover did not go to sleep today even after ground controllers sent commands twice for it to do so.

Shortly before noon, controllers were surprised to receive a relay of data from Spirit via the Mars Odyssey orbiter. Spirit sent 73 megabits at a rate of 128 kilobits per second. The transmission included power subsystem engineering data, no science data, and several frames of "fill data." Fill data are sets of intentionally random numbers that do not provide information.

Spirit had not communicated successfully through Odyssey since the rover's communications difficulties began on Wednesday.

"Number 5 is ALIVE!!!"

[Jon P. Inghram]

Doh, I just noticed I misspelled Spirit when I started this thread!

[Jon P. Inghram]

They've got Spirit back into a stable condition, turns out there was something wrong with the flash RAM storage or the software they use to interface with it. They were able to command the rover to switch to what they called a "cripple mode" that doesn't use the flash RAM for storing data, only the volatile RAM that's normally only used in the "conventional" personal computer sense, and when that was done the computer stabilized and stopped it's reset loop. They then reset the command loss timer and told the rover to go to sleep mode, then a little while later asked it to respond if it heard them. It didn't respond which indicated that it did indeed go to sleep, exactly the way it was supposed to.

At least a portion of the operating system is stored in EEPROM, which is what is first loaded when the computer powers back up from sleep. They'll need to return the computer to it's "cripple mode" every morning until they either fix the issue with the flash RAM if possible or end up having to upload new software to the EEPROM and just performing the rest of the mission without any permanent storage.

[MultimediaMan]

Cool. They may have to do some fancy code re-writing, but where there is a will, there is a way.

[GT98]

Sprits Twin, Oppertuninty landed successfully this morning also. Wonder if they'll run into the same problems

[MultimediaMan]

GT98: Opportunity probably has the same problem...Mission Software Engineers are confident it's a software problem. There is a fix in the works, and since they have the cause for Spirit, they will avoid the problem with Opportunity.

Spirit has been restored to pretty much normal operation for the time being: Spirit is sending back pictures as we speak.

Rest assured they will test, test, test and test some more before uploading any new Software for the Rovers.

[cjolley]

Originally posted by MultimediaMan
...Engineers are confident it's a software problem...

I never thought I would hear myself say these words:
Software Problem!? Thank God!!!!

chuck

[MultimediaMan]

Yeah, kinda hard to FedEx a new Flash RAM card out there, ya know?

[cbman]

It would be funny just to call it in though... LOL Especially on their automated system

[cjolley]

Got em covered


chuck

[gt40]

LOL.
what happens when the fedex guy gets there and there's no air
And who's gonna sign for it??
I don't think Spirit has been programmed for that eventuality.

[cjolley]

hmmm....
I probably should have shipped it USPS*.

chuck


*United Space Postal Service.