Bradley D. LaRonde (brad@ltc.com) writes:
> Also (with similar caveats), I notice that it is called a Vr4111
> (vs. Vr3111), which leads me to reason that NEC probably considers
> it part of the R4000 family.
The Vr41xx CPU core is NEC's first attempt to implement a MIPS CPU (as
opposed to building a MIPS-designed CPU like R4400, or working as part
of a MIPS design team like Vr4300).
It is a clone of the R4000 architecture - a 64-bit CPU running most of
the MIPS-3 core instruction set. The TLB is R4000-like, but then all
recent MIPS CPU TLBs are R4000-like, since anything else won't ever
run Windows CE.
I know it fails to provide the (core MIPS-3) instructions LL/SC,
because it's designers erroneously thought they were only useful for
multiprocessor systems. Otherwise, it should be pretty compatible.
Dominic Sweetman
Algorithmics Ltd
dom@algor.co.uk
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