按照模型机写出指令ADD A(R2),R8的操作流程。(输入请大写英文) FT: PC->MAR PC+1->PC READ M MDR->IR ST: PC->MAR PC+1->PC READ M MDR->X A+(填空1)>MAR READ M MDR->SR DT: (填空2)->DR ET: DR+SR->BUS BUS->(填空3)答案 R2 #R8#R8 ...