Official Solution for Exam 2 CS 15-347 Spring 1997 ----------------------------------------- PROBLEM 1. unsign 2-comp biased sign mag 000 0 0 -4 0 001 1 1 -3 1 010 2 2 -2 2 011 3 3 -1 3 100 4 -4 0 -0 101 5 -3 1 -1 110 6 -2 2 -2 111 7 -1 3 -3 ----------------------------------------- PROBLEM 2. c0 c1 c2 c3 c4 c5 c6 c7 c8 c9 c10 c11 lw1 f d e m w addu2 f d e m w addu3 f d e m w lw4 f d e m w addu5 f d d e m w lw6 f f d e m w sw7 f d e m w (Note: you could also stall EX in addu5 instead of ID) arcs: (inst:stage) lw1:m -> addu3:e addu2:e -> addu3:e addu3:e -> lw4:e lw4:m -> addu5:e addu5:e -> lw6:e addu5:m -> sw7:e lw6:m -> sw7:m ----------------------------------------- PROBLEM 3. 3 4 5 6 7 8 9 10 11 12 13 andi f d e m w - - - - - - BNEL - f d e m w - - - - - addui - - f d e m w - - - - BEQL - - - f d be - - - - - addui - - - - f bd - - - - - BEQL - - - - - f d e m w - addiu - - - - - - f d e bm - sll - - - - - - - f d e m or - - - - - - - - f d e ----------------------------------------- PROBLEM 4. s1 s2 s3 s4 s1 - d o n s2 - - a o s3 - - - d s4 - - - - ----------------------------------------- PROBLEM 5. a. parallel b. not parallel c. parallel d. not parallel e. parallel ----------------------------------------- PROBLEM 6. a. 8 clocks b. R I G H T c. 5 clocks ----------------------------------------- PROBLEM 7. a. F b. T c. T d. F e. F f. F g. F h. F ----------------------------------------- PROBLEM 8. A. normalized denormalized bit pattern exp weight mantissa mantissa 00 1/2 1 0 01 1/2 5/4 1/4 10 1 3/2 1/2 11 2 7/4 3/4 B. significand exp 00 01 10 11 00 0 1/8 1/4 3/8 01 1/2 5/8 3/4 7/8 10 1 5/4 3/2 7/4 11 2 5/2 3 7/2