MIPS (Microprocessor without Interlocked Pipelined Stages) is a reduced instruction set computer (RISC) instruction set architecture (ISA) developed by MIPS Computer Systems, now MIPS Technologies, based in the United States.
- MUX
- Sign - Extender
- Adder
- ALU
- ALU Control
- PC updte Control
- Register File
- Program Counter
- Register
- Program Memory
- Data Memory
| Function | ALU Control | Semantics |
|---|---|---|
| AND | 0000 | F = A and B (bitwise AND); Z update, V,C = zero |
| OR | 0001 | F = A or B (bitwise OR); Z update, V,C = zero |
| add | 0010 | F = A + B; Z,V,C update |
| sub | 0110 | F = A - B; Z,V,C update |
| slt | 0111 | F = (A < B) ? 1 : 0 |
| NOR | 1100 | F = ~ ( A or B ) (bitwise NOR); Z update, V,C = zero |
| Register | Number | Conventional Name Usage |
|---|---|---|
| $0 | $zero | Hard-wired to 0 |
| $1 | $at | Reserved for pseudo-instructions |
| $2 - $3 | $v0, $v1 | Return values from functions |
| $4 - $7 | $a0 - $a3 | Arguments to functions - not preserved by subprograms |
| $8 - $15 | $t0 - $t7 | Temporary data, not preserved by subprograms |
| $16 - $23 | $s0 - $s7 | Saved registers, preserved by subprograms |
| $24 - $25 | $t8 - $t9 | More temporary registers, not preserved by subprograms |
| $26 - $27 | $k0 - $k1 | Reserved for kernel. Do not use. |
| $28 | $gp | Global Area Pointer (base of global data segment) |
| $29 | $sp | Stack Pointer |
| $30 | $fp | Frame Pointer |
| $31 | $ra | Return Address |
