1. Why would DMA be useless if the computer did not have interrupt capability?

2. What is the advantage of using a disk controller to control the hard disk? How else could you do the job that the disk controller does?

3. Consider the interrupt that occurs at the completion of disk transfer.

a. "who" is interrupting "whom"?

b. Why is the interrupt used in this case? What would be necessary if there were no interrupt capability on this computer?

c. Describe the steps that take place after the interrupt occurs.

4. What is polling used for? What are the disadvantages of polling? What is the better way to perform the same job?

5. What is the difference between polling and polled interrupt processing?