Re: 8051 architecture question


"Neil Kurzman" <nsk@xxxxxxxxxxxx> wrote in message
news:427AFF65.EFE6844@xxxxxxxxxxxxxxx

> 3-Internal RAM 256 Bytes Max
> The internal RAM overlays the 128 bytes of Register Space.
> It gets confusing here. You get the full 256 bytes of internal RAM Plus
> the registers. ( there are some overlapping instructions).

On the plain 8051, you don't get the full 256 bytes internal RAM:
you get 128 RAM + 128 SFRs. It is only on the '52 architecture
that there is a full 256 bytes of internal RAM: the upper
128 bytes overlaying the SFRs (you use indirect or direct
addressing to disambiguate)

Richard [in PE12]


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