[sdiy] Strange uController behaviour (slightly OT)

[Tom Arnold]

On Fri, May 16, 2003 at 01:05:11AM +0200, Alex Stettler wrote:
> The strange behaviour of the uController is, that if the EPROM-window is
> covered with opaque tape as this is usually done with EPROM-devices, the uC
> works more or less correct with only the LCD having nonsense characters on
> the screen. As soon as I remove the black tape, the uC works perfect!

Havent had this problem with uControllers, but have with EPROMs.
Are you sure when it was erased it was cooked long enough?  I had some
EPROMs exhibit this exact problem ( worked with some light exposure but not
in the dark ).  Tested blank after erasure.  Drove me nuts because all 8
EPROMs ( used one at a time ) did the same thing.  Drove me more nuts because
unit would work with the lid off, but only about 10% of the time with the lid
on.  I know, I was lazy and didnt tape them like I should have.  Reason why
it worked 10% of the time?  Depending on how it was booted, there was an
internal diagnostic light that came on....

Root Cause : Dying lamp in bulk eraser.  Went an extra 20% and the EPROMs
worked fine.

-- 
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 - Tom Arnold -       When I was small, I was in love,                  - 
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