> The PIC-range processors have harvard architecture, meaning that data
> memory is separated from program memory. You cannot read the program rom ->
>you cannot checksum.

The Analog Devices fixed point DSP chips are also Harvard architecture (or
is it 'modified' Harvard artchitecture?), but they were clever enough to
include a bus exchange for transferring between program and data space.
They use a dedicated register to hold the extra byte (program memory is 24
bits, data memory is 16 bits).

I've always wondered why Microchip didn't do something similiar.


newell