On Tue, 20 Nov 2001, Andrew E. Kalman wrote:

> Wouter wrote:
>
> >So your potential customer/data thief can put any program in the ROM he
> >wants. In that case I don't see how you can prevent that he reads the data
> >EEPROM, while at the same time your program can read it. The best you might
> >do is that he can not make sense of what he reads, but that is anoter
> >matter.
>
> I believe there is another option, and this is what I'm working towards.
>
> I'm assuming that it is not possible to selectively erase, say, the
> program memory without also causing the EEPROM contents to revert to
> 0xFF for every cell. I.e. bulk erase erases both program memory and
> EEPROM memory.
>
> Is my assumption correct?

Nope.  Sorry.  Bulk erase the '877 and the EEPROM data is still there,
grinning at you.

> Sound plausible / correct / possible?

Yeah, right up until that first part...  <grin>

Dale

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