From:  Dean Swan at MITEL on 10/18/2000 09:58 AM

Andreas,

>(I thought that a definition of _SH3_ implies _MIPS_ since it's basically a
mips variant)

     Just FYI, the SH3 is *not* a MIPS variant.
See http://www.byte.com/art/9707/sec4/art2.htm for a good overview of
the SH3 architecture.  The SH3 has 68 instructions and all instructions
are a fixed 16 bit length.  This is even different from the MIPS 16
Application Specific Extension, which limits you to only 8 general
purpose registers.  (MIPS 16 ASE is similar to ARM-Thumb in that it
doesn't have access to *all* of the processor resources, whereas the
SH3 instruction set uses 16 bit long instructions and *does* have
access to all the processor resources).

     I imagine that it's for historical reasons (MIPS is older), as
well as the SH3 being proprietary to Hitachi that make MIPS more
popular.

                              -Dean Swan
                              dean_swan at mitel.com