Computer Organization Lecture 17

1. Computer OrganizationLecture 17 Controller design Microprogramming overview University of Portland School of Engineering

2. From Lecture 12 MIPS controller Outputs Outputs Inputs IR(31:25) University of Portland School of Engineering

3. Outputs Inputs NS Decoder Output Decoder Present State Flip Flops Combo logic ROM MUX Decoder Combo logic ROM MUX FSM architecture University of Portland School of Engineering

4. Ten one-bit outputs University of Portland School of Engineering

5. Three two-bit outputs University of Portland School of Engineering

6. 2 Clk 1-3 Clk State diagram overview All instructions require IF, ID (2 clk’s) University of Portland School of Engineering

7. Full FSM state diagram Inputs:Op Outputs: 13 signals States: 10 University of Portland School of Engineering

8. MDP16 controller Inputs IR(15:0) Outputs University of Portland School of Engineering

9. Outputs Inputs NSD ROM Output Decoder PS flip-flops Controller architecture ROM contains microprogram University of Portland School of Engineering

10. Controller overview • Inputs: IR[0:15], EQ • Outputs: ~15 signals • Present state: 32-bits • NSD or ROM: 256x32 University of Portland School of Engineering

11. NSD PS Inputs Outputs MDP16 controller University of Portland School of Engineering

12. Controller outputs University of Portland School of Engineering

13. Controller outputs, continued. University of Portland School of Engineering

14. Controller outputs, continued. University of Portland School of Engineering

15. Controller outputs, continued. University of Portland School of Engineering

16. Controller internals University of Portland School of Engineering

17. Which output is asserted? University of Portland School of Engineering

18. Microprogramming overview • Review instructions, understand goals • Determine state diagram • Microprogram individual instructions • List tokens on one line • Repeat for remaining clocks • Merge all instructions • Test, test, test University of Portland School of Engineering

19. .upg .txt B2Logic MicroAsm Source File Object File Assembler ROM Microprogramming steps ROM contents defined by assembler University of Portland School of Engineering

20. MicroAsm • Java application: MicroAsm.class, SavitchIn.class • Microinstruction: free format, no fixed fields • Requires input file: text-only, file.upg • Creates output file: file.txt • Errors: command line file name,file I/O, unrecognizable token • Execution: BlueJ or DOS command line University of Portland School of Engineering

21. BlueJ execution Must pass input file name to main method University of Portland School of Engineering

22. Output file defines control ROM Address Data University of Portland School of Engineering

23. MDP16 op codes University of Portland School of Engineering

24. MDP16 op codes, continued. University of Portland School of Engineering

25. How many microinstructions? University of Portland School of Engineering

26. How many microinstructions? University of Portland School of Engineering

27. A B Reset Lw or Sw R-fmt C Beq Jump G I J Sw Lw D F H E Partial MDP16 state diagram University of Portland School of Engineering

28. ID IF Reset 2 clocks sll srl lw sw R-fmt nop 1- 3 additional clocks j beq addi subi andi ori MDP16 state diagram University of Portland School of Engineering

29. University of Portland School of Engineering

30. Which output is asserted? University of Portland School of Engineering

31. How many microinstructions? University of Portland School of Engineering

32. How many microinstructions? University of Portland School of Engineering