Answers to

Quiz - Chapter One (lectures)

CIS343

(1-3) List the three steps of the Fetch-Execute Cycle.

1.

2.

3.

Fetch instruction pointed to by PC

Increment PC by instruction size

Decode & execute instruction

4. What does it mean to “fetch” an instruction?

Copy it from RAM to IR

5. During program execution, how is a jump or a branch accomplished?

Address in the PC is changed

6. Is instruction cycle synonymous with machine cycle?

No, execution of one instruction may require several machine cycles

7. What is the purpose of an instruction format?

To specify the role of each field of the instruction

8. Can the design of a machine’s addressing mode have an effect on locality?

Yes, an addressing mode may require access to memory locations not in proximity to each other

9. The lowest level instructions that directly control a microprocessor is called . . .

microcode

10. In modern PC microprocessors, the microcode is _____.

hardwired

(11-17) Identify these stages in the development of operating systems.

11. The scheduling and loading functions were turned over to a program called the monitor. Jobs were grouped together and run in batches.

Simple batch systems

12. A computer operator was put in charge of the machine.

Operator controlled machines

13. Computers did not have software. To reprogram the machine required rewiring. Prehistory

14. A user on a PC runs several processes at once.

Single user multiprogramming

15. The user was given interactive access to the machine via a command line interface.

Interactive multiprogramming

16. Several jobs are read into memory, allowing the processor to switch back and forth them.

Multiprogrammed batch systems

17. User time was scheduled. Users had to load their programs along with system software needed by their job.

User setup and breakdown

18. Clarify the usage of the terms multiprogramming, multiprocessing and multitasking.

Multiprogramming and multitasking as synonymous. Multiprocessing is multiprogramming on a multiprocessor.

19. Clarify the role locality plays in OS concerns.

Many programs exhibit a high degree of locality. OS designers work to take advantage of that fact to get better usage of resources.

20. Clarify the role of time in locality issues.

To be useful in OS design, clustered memory references must take place within a short time frame.