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HW12

(10 points) Describe the effect that a single stuck-at-0 fault (i.e. regardless of what it should be, the signal is always 0) would have for the signals shown below, in the single-cycle datapath in Figure 4.17, on page 265. Note that the ALUOp signal is two bits in size, LSB and MSB refer to the least-significant and most-significant respectively. Which instructions, if any, will not work correctly? Explain why.

  1. RegWrite = 0

  2. ALUOp (LSB) = 0

  3. ALUOp (MSB) = 0

  4. Branch = 0

  5. MemRead = 0

  6. MemWrite = 0

Datapath for reference: