On Wed, 19 Nov 1997 22:18:32 +0000, you wrote:

>In article <347358DC.7B0539D5@sunada.com>, Matt Bonner
><mbonner@SUNADA.COM> writes
>>MChip's official position is that code-protected devices cannot be
>>erased.  I have done some playing around and have found that they _can_
>>be erased.  These are my observations:
>> 1. Some 74As can take many hours to erase (3 or 4).
>> 2. Code-protected parts tend to erase faster if they've been programmed
>
>Thanks - I'll give them a good soaking!
>
>What's really hacked me off about this is Microchips failure to put this
>in the data sheet (although someone said it was on the CDROM - which I
>havent got).

Yes it is, surely everyone knows that the phrase ;
 "Note : Microchip does not recommend code-protecting windowed
devices"
really means 
"WARNING ! You will probably never be able to re-use them", 
don't they ? It's even printed in a nice shaded box, just so you know
they mean it!  :-)  


>Their latest 16CXX data sheet doesn't mention it at all - which I think
>borders on the criminal.  It should be up there in bright shiny red 36
>point letters...!
>  ..still I guess it makes them a few more sales..
Maybe, but I suspect incompetence rather than marketing reasons - look
at all the bugs they put in their apnotes especially to teach people
PIC programming the hard way by finding them all :-)
>I'll let you know if I recover them..
>
>Jim

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