Those of you with experience reading cores, we need your help in
reading out a LVDC core stack.
Ouch!. I don't have much experience of reading core, but I've worked on
core memory systems (I guess many others here have too).
Rememebr that reading core is destructive. Basically, the read operation
is to write a 0 to each core and see if there was a change in magnetic
flux in that core. If there was, it _was_ a 1. If not, it was (and still
is) a 0. Normally you then write the 1 back if appropriate.
So the first problem is that if anything goes wrong, if the snese
amplifier doesn't work, or whatever, then you lose the contects of the
core stack. You don't get a second change.
The second problem is that from what I've read on core memory, the
waveforms applied to the X and Y address wires are critical. Not just in
amplitude, but also in things like rise time. Get the former wrong (at
least) and you might corrupt cores other than the one you're trying to read.
How much data on the origianl core controller still exists? Any
scheamtics? Any comments on wht had to be tweaked for each core stack?
And hardware still around (particularly the controller for _this_ stack)?
If successful, this will likely be the only example of
the LVDC flight
software left in existence.
And if unsuccessful there will be no examples left :-(
-tony