Interrupts

Question 1

What can provide an interrupt?

Answer 1

Interrupts can be provided by hardware or software

Question 2

When do hardware interrupts occur?

Answer 2

Hardware interrupts occur when devices indicate they need attention

Question 3

When do software interrupts occur?

Answer 3

When programs detect an error or illegal operation

Question 4

What happens when an interrupt takes place?

Answer 4

• Stores interrupted task
• Interrupt service routine is carried out
• Then the data is retrieved from the stack and the interrupted task continues

Question 5

How does the computer store the interrupted task?

Answer 5

-The values of each register and the PC are put onto the system stack

Question 6

How does the computer continue the interrupted task?

Answer 6

• The contents of the registers and program counter from the original task are restored from the stack they were placed on