3 Feb
2001
3 Feb
'01
6:10 a.m.
At 10:14 AM 2/3/01 -0800, Chris Kennedy wrote:
Iggy Drougge wrote:
...
Particularly in space-based applications, where flight qualification for
man-rated hardware is a pangalactic bitch.
I'm confident that I read about 8 years ago that IBM won & delivered on a
contract to redesign the flight computers using more modern
technology. Besides getting rid of the core, they added more banks of
memory so that it wasn't necessary to load different flight sequences from
tape while the mission was going on.
The redesigned the computer, bug for bug. There is no separate code base
or tools -- it is functionally identical, IIRC.
A quick search on Google turned up some stuff. I'm not sure this is the
best link, but it has some details about the system and the redesign:
http://spaceflight.nasa.gov/shuttle/archives/sts-72/shutref/sts-av.html
-----
Jim Battle == frustum(a)pacbell.net
BTW, I read somewhere that the space shuttle
actually used core memory,
apparently due to the bad resistance towards radiation in older IC memory.
...
Could anyone confirm whether this still holds
true?
I have no idea if the processors are being swapped out as part of the
flight deck modernization program. If so it can't be too radical a
departure from the existing architecture, since only one orbiter has
completed that modification cycle and the thought of having two
sets of tools for building the code loads for the orbiters staggers the
mind.