EPROM erase times and lifespan

[Philip Pemberton]

Mr Ian Primus wrote:
> That's interesting! Did the thing work after being restarted, or was the
> data permanently altered? It doesn't take much to disrupt running software,
> after all.

It was a temporary glitch -- I power-cycled the board and it worked again.

> I remember one article that described an incredibly creative, low cost
> digital camera-like device. Instead of a CCD, the thing used an ordinary
> DRAM chip with the cover pried off. The light would affect the cells of the
> DRAM, and then the 'image' could be read by the computer. Of course, the
> thing was incredibly primitive - the pictures weren't great, but it was an
> ingenous hack, and a clever utilization of the light-sensitive nature of
> these things.

"Kuckuck", by Martin Kurz -- <http://www.vampyr.msk.ru/electroniks/kuckuck.zip>

Interesting, even if you don't read German. The source code, schematics and 
pretty diagrams explain most of it :)

Basically you fill the DRAM with "1" bits, then read it back out after a 
predetermined time. That gives you an image. Take more than one image and you 
can even get a greyscale image :)

-- 
Phil.
classiccmp at philpem.me.uk
http://www.philpem.me.uk/