NATIONAL OPEN UNIVERSITY OF NIGERIA

UNIVERSITY VILLAGE, PLOT 91, CASDASTRAL ZONE, NNAMDI AZIKIWE EXPRESS WAY, JABI, ABUJA.
FACULTY OF SCIENCES
OCTOBER 2013 EXAMINATION

COURSE CODE:           CIT 309

COURSE TITLE:            COMPUTER ARCHITECTURE

CREDIT UNIT:              3 CREDIT UNITS

TIME:                           2 ½ HOURS

INSTRUCTION: ANSWER ANY FOUR QUESTIONS IN ALL

1a.       What is Processors instruction set?                                                                                        (5.5 marks)

1b.       Write short note on the four register involved in the Fetch Cycles.                                      (12 marks)

2a.       Write a short note to differentiate between the Operation code and Next instruction reference (11 marks)

2b.       What is Instruction address calculation (ac)?                                                                        (6.5 marks)

3a.       Write short note on Incrementer /decrementer address latch.                                            (6.5 marks)

3b.       Enumerate the two key characteristics of a process.                                                            (11 marks)

4a.       Write short note on the benefit of Incrementer/decrementer address latch over the ALU. (4.5 marks)

4b.       Define gates and list the four basic gates used in digital logic.                                            (13 marks)

5a.       Write down the steps to perform; ADD B, A                                                                          (9.5 mark)

5b.       State the four Characteristics of Reduced Instruction Set Architectures.                             (8 mark)

6a.       What is Interrupt control?       (5.5 Marks)

6b.       State and write short note on the three micro-operations that can be performed within the time of a single time unit.    (12 Marks)