Computer Organization

Q2. 4.2 The basic single-cycle MIPS implementation in Figure 4.2 can only implement some instructions. New instructions can be added to an existing Instruction Set Architecture (ISA), but the decision whether or not to do that depends, among other things, on the cost and complexity the proposed addition introduces into the processor data path and control. The first three problems in this exercise refer to the new instruction: Instruction: LWT Rt, Rd (Rs) Interpretation: Reg[Rt] =Mem [Reg[rd] Reg[Rs]] 4.2.1 [10] $4.1> Which existing blocks (if any) can be used for this instruction? 4.2.2 [10] $4.1> Which new functional blocks (if any) do we need for this instruction? 4.2.3 [10] What new signals do we need (if any) from the control unit to support this instruction? Branch Add Add M ALU operation Data PC Address Instruction Register # Registers Register # M MemWrite ALU Address Zero Data memory Instruction memory Register # RegWrite Data MemRead Control