GATE 2013
April 5, 2025GATE 2013
April 5, 2025GATE 2013
| Question 29 |
Consider the following sequence of micro-operations.
MBR ← PC
MAR ← X
PC ← Y
Memory ← MBR Which one of the following is a possible operation performed by this sequence?
| Instruction fetch | |
| Operand fetch | |
| Conditional branch | |
| Initiation of interrupt service |
Question 29 Explanation:
We know PC holds the value of the next instruction to be executed. Here the value of PC is stored in MBR( MBR ← PC ) and then to the memory (Memory ← MBR). We are saving the value of PC in memory and a new address is loaded into the PC (PC ← Y), so we start executing from the new address Y which is loaded into PC. So this behaviour matches with the interrupt service execution as we have already saved the address of current running instruction into memory and then we are loading new address in to the PC and start executing from there.
Hence option D is the answer.
Hence option D is the answer.
Correct Answer: D
Question 29 Explanation:
We know PC holds the value of the next instruction to be executed. Here the value of PC is stored in MBR( MBR ← PC ) and then to the memory (Memory ← MBR). We are saving the value of PC in memory and a new address is loaded into the PC (PC ← Y), so we start executing from the new address Y which is loaded into PC. So this behaviour matches with the interrupt service execution as we have already saved the address of current running instruction into memory and then we are loading new address in to the PC and start executing from there.
Hence option D is the answer.
Hence option D is the answer.