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The following are some events that occur after a device controller issues an interrupt while process L is under execution? (P) The processor pushes the process status onto the control stack. (Q) The processor finishes the execution of the current instruction. (R) The processor executes the interrupt service routine. (S) The processor pops the process status of from the control stack. (T) The processor loads the new PC value based on the interrupt. Which one of the following is the correct order in which the events above occur?

The following are some events that occur after a device controller issues an interrupt while process L is under execution? (P) The processor pushes the process status onto the control stack. (Q) The processor finishes the execution of the current instruction. (R) The processor executes the interrupt service routine. (S) The processor pops the process status of from the control stack. (T) The processor loads the new PC value based on the interrupt. Which one of the following is the correct order in which the events above occur? Correct Answer QPTRS

Whenever an interrupt occurs, CPU first finishes the current instruction before saving process status into the control stack and calling ISR.

After servicing the ISR processor resumes from same state using process status saved on the top of the stack.

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