At 12:00 -0600 1/29/09, Jules wrote: I would be pretty nervous about trying that. Knowing how solar cells work, and having seen cosmic-ray induced latchups destroy chips, it just seems like begging for trouble putting energetic photons onto a powered chip if you don't need to. Of course, EPROMs are cheap, and experimenting might be fun, but if you do this, I'd start with easily replaceable EPROMS. Shutting off the lamp and doing a blank-check, then turning it back on, would work, as would covering the chips with a UV-shade. I don't see much problem with that. -- - Mark 210-379-4635 ----------------------------------------------------------------------- Large Asteroids headed toward planets inhabited by beings that don't have technology adequate to stop them: Think of it as Evolution in Fast-Forward.