2014-04-26 10:52:28 -04:00
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magic smoke
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2014-04-26 11:54:15 -04:00
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n. A substance trapped inside IC packages that enables them to function
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(also called blue smoke ; this is similar to the archaic phlogiston
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hypothesis about combustion). Its existence is demonstrated by what happens
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when a chip burns up the magic smoke gets let out, so it doesn't work any
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more. See smoke test , let the smoke out. Usenetter Jay Maynard tells the
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following story: Once, while hacking on a dedicated Z80 system, I was
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testing code by blowing EPROMs and plugging them in the system, then seeing
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what happened. One time, I plugged one in backwards. I only discovered that
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after I realized that Intel didn't put power-on lights under the quartz
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windows on the tops of their EPROMs the die was glowing white-hot.
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Amazingly, the EPROM worked fine after I erased it, filled it full of zeros,
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then erased it again. For all I know, it's still in service. Of course, this
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is because the magic smoke didn't get let out. Compare the original phrasing
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of Murphy's Law.
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