This is a classic FAQ fare;  JW parts do this, as light can erase the
RAM bits inside the windowed part.  Something is being used without
being initialized <G>  (Many people get in the habit of covering the JW
windows after erasure for this very reason, that way bugs that won't let
OTP parts work are caught in the JW part versions of software.  Lots
cheaper to fix that way!)

  Mark Willis, mwillis@nwlink.com

John A. Craft wrote:
>
> This sounds like an  X file or something, but I have a circuit that has a
> 16c63/JW part in it.  If I apply power with the lights on, it works
> correctly, but if I cover (without touching) or turn off the lights, the
> thing doesn't init properly and doesn't run at all.
>
> Any ideas, (about the chip, not my sanity) suggestions.
>
> John C.
>
> John A. Craft                           (601)689-8100 Voice
> Vice President, Sr. Analyst             (601)689-8130 Fax
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