aj pollock wrote:
>
> Hello!
> I have two pic16c57/jw eprom chips that may be useless trinkets.
> After
> being re-programmed approximately 40 times, my programmer tells me
> they
> are not blank.
> They usually take about 5 minutes to erase.  I have left them in the
> eraser  for up to several hours.  A dump of each chip results in a 59
> byte file that contains the following code:
>
> :08100000FF0FFF0FFF0FFF0FB0
> :021FFE000000E1
> :00000001FF
>
> This is the same file that results from a dump of  an empty programmer
> socket.
> Are these chips dead? If they are, how and why?
> Any help will be appreciated.

As these get used over and over, they take longer to erase. On my trusty
old 16c54a (about 2 years old) it now takes about 45 minutes! I'll keep
using it out of curiosity to see if it fails permanently some time...

Dave Miga, EDS, Inc http://eds-inc.com