Olin Lathrop wrote:
> Yeah, I'm not real comfortable with the fact that the EEPROM can be
> changed from the host.  I'd rather set it once and enable some sort of
> write protection, but the EEPROMs they spec don't have that.  Oh well.
>
> I'll probably wake up holding the FTDI chip in reset and have the PIC
> checksum the EEPROM.  If it isn't right, it will load it before releasing
> the FTDI chip.
>

Have you checked the eeprom fm93CS46 from fairchild semiconductors? This
chip has indeed write protection (software and hardware controlled) and
some more "security" functions. It seems capable of the demanded 1MHz
operation, too.

Florian

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