magic smoke

	This is the JargonFile ^(V4.00) entry for magic smoke - Next: mail storm, Prev: magic number
:magic smoke: /n./ A substance trapped inside IC packages that enables them to function (also called blue smoke; this is similar to the archaic phlogiston hypothesis about combustion). Its existence is demonstrated by what happens when a chip burns up -- the magic smoke gets let out, so it doesnt work any more. See smoke test, let the smoke out. Usenetter Jay Maynard tells the following story: "Once, while hacking on a dedicated Z80 system, I was testing code by blowing EPROMs and plugging them in the system, then seeing what happened. One time, I plugged one in backwards. I only discovered that after I realized that Intel didnt put power-on lights under the quartz windows on the tops of their EPROMs -- the die was glowing white-hot. Amazingly, the EPROM worked fine after I erased it, filled it full of zeros, then erased it again. For all I know, its still in service. Of course, this is because the magic smoke didnt get let out." Compare the original phrasing of [[Murphys Law]].
* (text is auto-included via JargonExtension by mutante using jargon with VERSION 4.0.0, 24 JUL 1996 - JargonFile by Eric S. Raymond is in the public domain)