Re: 8051 architecture question

Ian Bell wrote:
JBrewster wrote:
Now are Program Memory and Data Memory 2 separate memory spaces?
Completely separate. This it what is known as a Harvard architecture where
code and data spaces are kept quite separate. In the 8051 you can have up
to 64K of each.

Fully agree. Just want to add that one can map the mcu signals in a way that both code and external memory are the same. Many development kits do this by default to allow the user to "upload" code into the external data memory of which a certain part will appear as the code memory.
Coding wise this leads to a point where movc and movx will access the same memory location. However this breaks the Harvard paradigm (ofcourse).

just my 2c,
Matthias
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