MIPS Architecture Documentation

Being both the pioneer for RISC designs and 64 bit CPU cores in general, the MIPS architecture has a track record in pushing the frontiers of CPU development. Though mostly used in embedded systems and appliances, the flexible MIPS core has been used in almost any kind of systems, from Cisco routers, Nintendo gaming devices and high performance SGI servers and workstations down to low power low performance embedded systems. A lot of companies license the MIPS core for its known extendability and reliability. The standard compiler for the MIPS CPU, the MIPSPro C Compiler is known to be among the most optimizing and reliable compilers in use today.
Today, most MIPS systems are embedded systems, SGI computers being an exception. On SGI servers and workstation the IRIX operating system is used, there are efforts to port Linux and other systems to it, though. As if anyone wants to use something different than IRIX on their SGI systems.

There are three different branches of the MIPS instruction set, called MIPS16 (used in embedded systems to save code size), MIPS32 (every MIPS CPU supports that) and MIPS64. The instruction set itself has four revisions, each being backward compatible. The latest is known as 'MIPS IV'.

File Size Description Source
MIPS32 Vol.1: Introduction to the MIPS32 Architecture v0.95 (pdf) 925 kb A good primer to start with MIPS
MIPS32 Vol.2: The MIPS32 Instruction Set v0.95 (pdf) 2226 kb The complete instruction set reference MIPS
MIPS32 Vol.3: The MIPS32 Privileged Resource Architecture v0.95 (pdf) 1045 kb MIPS
MIPS64 Vol.1: Introduction to the MIPS64 Architecture v0.95 (pdf) 1136 kb The same with 64 bits MIPS
MIPS64 Vol.2: The MIPS64 Instruction Set v0.95 (pdf) 3164 kb MIPS
MIPS64 Vol.3: The MIPS64 Privileged Resource Architecture v0.95 (pdf) 1140 kb MIPS
MIPS IV Instruction Set v3.2 (pdf) 1188 kb Complete instruction set reference MIPS
MIPS R4000 User Manual 2nd Edition (pdf) 2051 kb The workings of the R4000 MIPS CPU MIPS
MIPSpro Assembly Language Programmers Guide (pdf) 354 kb Assembly Language programming on the MIPS and a bit instruction set specifica SGI
MIPSpro N32 ABI Handbook (pdf) 140 kb IRIX specific ABI information for the N32 ABI SGI

Further MIPS and IRIX related information is available from the SGI Techpubs website and the MIPS Publications Directory.