Microinstructions For Key Instructions
Example :
ADD R1,R2,#5 //R2 = A , R1 = 0
SUB R3,R4,#3 //R4 = 8 , R3 = 0
-->
T1 : (MAR) <-- (PC)
T2 : MBR <-- (MEMORY)
PC <-- PC + I
T3 : IR <-- (MBR)
T4 : R1 <-- R2 + 5
T5: (MAR) <-- (PC)
T6: MBR <-- (MEMORY)
T7: IR <-- (MBR)
T8: R3 <-- R4 - 3