On Wed, 30 Aug 2000 12:51:51 GMT, you wrote:

>Hello to all.  I require help to try and survive a horrible blunder by
>Microchip.
>
>On the F87X flash series, Microschip seemed to adopt a miserable =
philosophy
>with regard to the copy protection on this chip.
>
>If I leave the chip flash writeable, so I can update my code with my own
>bootloader program, the code must remain naked so that anyone can drop =
the
>chip in a programmer and read its contents.
>
>If I code protect the chip, it becomes non-flashable.
>
>I am sure many of you are aware of this limitation.
>
>Has anybody discovered a way to disable external reads and internal =
reads of
>the flah but still writing over existing flash locations?

Probably the only way to improve things on the current chips is to
have your main code periodically call routines in your bootloader
area, which can be write- and read- protected. This would at least
stop people being able to use a direct copy of your chip.
 =20

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