I talked to som Microchip Engineers at the masters conference in Arizona
this summer and was told there is no problem "cooking" the chips in the
eraser. They do state that if you set the code protect the chip will not
erase but I have seen some erased in a lon period of time. I believe they
are still refining the way code protect works and it may be in the  future
the chip will never erase. If you want to set code protect use an OTP. When
you program windowed parts always check the code protect status.


At 06:21 PM 8/13/97 -0400, you wrote:
>Don't sweat the fluorescent lighting.  It takes me a couple of minutes to
>erase most PIC's with my DataErase II, about 60 to 240 minutes with a
>commercial U/V (black light) tube, and I've left PIC's and Eproms under
>fluorescent light for weeks with no damage.
>
>The short times described in the original post are with high intensity U/V
>tubes like that in the DataErase.
>
>
>CIAO - Martin R. Green
>elimar@bigfoot.com
>
>----------
>From:   Shane Nelson[SMTP:i@CHEETAH.SPOTS.AB.CA]
>Sent:   Wednesday, August 13, 1997 3:39 PM
>To:     PICLIST@MITVMA.MIT.EDU
>Subject:        Re: frying a PIC
>
>On Wed, 13 Aug 1997, Andy Kunz wrote:
>
>> >I have a dozen 'c54 chips that won't erase. I'm thinking I probably
>fried
>> >them with too much current...
>>
>> Probably.  '54 usually is a couple minutes, even when cp'd
>>
>> Andy
>
>Couple minutes?? Wow. I find they need at least 20. I wonder if it's
>possible to damage them by UV exposure, or  by just leaving them
>under normal flourscent lighting.. I usually don't cover the window when
>testing.
>
>-Shane.
>
>
Larry G. Nelson Sr.
L.Nelson@ieee.org
http://www.ultranet.com/~nr