"Paul B. Webster VK2BZC" wrote:
>   If you could add code to a protected chip, you could write in a "read"
> routine to send it all back *out* again via the UART.  I think that's
> the reason.

I'm not sure how that could be achieved when the ROM is being modified
by resident protected code inside the chip itself. This code would be
written underneath the 'umbrella' of the code protection, but you cannot
access this code or write to ROM from the outside world without having
the code protection off or erasing the chip.

It's a bit like a gate with a padlock on it. You can't get in or out
without a key, (or breaking down the gate). The key in this case is
knowing how the boot loader functions.

The other scenario is generating 'smart' code that can alter itself
according the the conditions that it is subject to. You cannot do this
with a code protected chip either and the gateway doesn't exist.

--
Best regards

Tony

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