Introduction - If you have any usage issues, please Google them yourself
The R4000 processor provides complete application software
compatibility with the MIPS R2000, R3000, and R6000 processors.
Although the MIPS processor architecture has evolved in response to a
compromise between software and hardware resources in the computer
system, the R4000 processor implements the MIPS ISA for user-mode
programs. This guarantees that user programs conforming to the ISA
execute on any MIPS hardware implementation.