1. Digital circuits UL, FRI Lab 9, MIPS processor

2. Logisim - nastavitve  Logisim-win-2.x.x.exe  Libraries: Project – Load Library  Built-in Library: ( Memory, Plexers, Arithmetic, Input/Output, Legacy )  Logisim Library: 7400-series-rev1.circ  JAR Library: CS316.jar Class name: edu.cornell.cs316.Components  File: MIPS procesor.circ

3. Osnovne komponente procesorja  Memory:  Instruction(Read),  Data (Read & Write)  Registers (32 x 32bits):  RS  RT  RD M Trebar3  Program counter (PC)  Instruction register (IR)  Aritmetic & logic unit (ALU)  Incrementer (Adder)  Multiplexser (MX)  Sign Extend  ZeroExtend  Task 1: Find the module in logisimu and write down all control signals.

4. Memory RD Addr Instructions RD Addr WD Data M Trebar4 A – address D – data (Input/Output) sel: Chip select (0 – disable) ld: 1 – load mem to output clr:Clear: PC – instruction address Op – instruction out

5. ROM, Register file RA1 RD1 RD2 RA2 WA WD M Trebar5 Register file Control signals

6. Register, MUX IR PC M Trebar6 MX 2/1 MX 4/1

7. Adder, ALE M Trebar7 A B ALUout ALU-function A B A+B MIPS procesor.circ ALE operation: 000: X+Y, 001: X+1, 010: X-Y, 011: X*Y 100: X/Y, 101: << X – shift left, 110: X>> - shift right

8. Task 2 – instruction fetch in ‘logisim’  Define the circuit to fetch instruction in 32-bit MIPS processor (‘logisim‘)  Processor units:  Program counter – PC (32-bitov)  adder - + (32-bitov)  Instruction memory (ROM) (…. x32-bitov)  Instruction regiter – IR (32-bitov)  Program counter has Reset function – use button.  Use CLK signal to write data to registers  Test the circuit for the MIPS instruction:  add $t2,$t3,$t4 (R2<-R3+R4)

9. Circuit to fetch the instruction in ‘logisim’ IR + 4 PC Ukazni pomnilnik RA ukaz Logisim circuit: