Here' an old geek trivia contest. What is this a picture of? Old geeks should remember what is is (hint). I'm certain many will recognise it but for the few who don't the answer is below. Thanks for playing along.
-Nick
answer: Core memeory, probably hand wired in Asia. This old technology was so reliable that the first space shuttle used it for a short time. Micro electronics made it obsolete.
Impressive! The buss wires down the middle made it clear that this was electronics, but I wouldn't have known the rest.
[Hint: I'm "old", but didn't become much of a computer geek in the early days. I did build a synthesizer out of a kit before chip circuitry made it obsolete. Hundreds of of resistors and capacitors connected with actual wire and solder! I wish I hadn't given it away; could make some interesting pictures if nothing else.]
It is an early and very old fashioned core memory array. The direction of the magnetic field could be set in any one of the little ferite cores by sending the right polarity combination down the intersecting wires for that core and that magnetic charge direction could be read the same way. The two states the charge could be in corresponded to the binary 1 or 0.
These arrays had very little capacity by todays standards and took up a huge amount of space too.
A gigabyte of memory using those things would fill up a train load of boxcars.
Good stuff, you know your old technology. These old core memories are immune to EMP's which will destroy today's electronics. Even so no one in there right mind would use today, for all the reasons you stated. You had to write real tight code when you had so little memeory. Thanks for the comments.
-Nick
nlamendo wrote:
Good stuff, you know your old technology. These old core memories are immune to EMP's which will destroy today's electronics. Even so no one in there right mind would use today, for all the reasons you stated. You had to write real tight code when you had so little memeory. Thanks for the comments.
-Nick
KNOW MY OLD TECHNOLOGY INDEED - I am old technology
BTW - the cores themselves might or might not be immune to EMP but an EMP would erase the data on them and fry the support electronics that was used to read and write them. If an EMP can take down a high voltage power grid what chance do you think those little guys would have?
The below quote is from Wikipedia, I should have read it more carefully before claiming it was immune from EMP, but the statement below, if accurate, made it sound like it had an advantage over MOS memory.
"Core memory is non-volatile storage – it can retain its contents indefinitely without power. It is also relatively unaffected by EMP and radiation. These were important advantages for some applications like military installations and vehicles like fighter aircraft, as well as spacecraft, and led to core being used for a number of years after availability of semiconductor MOS memory (see also MOSFET). For example, the Space Shuttle flight computers initially used core memory, which preserved the contents of memory even through the Challenger's explosion and subsequent plunge into the sea in 1986."
And therein lies your problem. Wikipedia is an "open" reference that can be modified and updated by just about anybody whether or not they know what they are talking about or if their info source is accurate. I don't know why anyone who really wants information they can trust would go to wikipedia.
