Fundamentals of Computer Architecture

Question 1

What is meant by the phrase: Stored Program Concept?

Answer 1

• A program’s instructions must be resident in main memory for it to be executed.
• These instructions are fetched and executed one at a time by the processor.

Question 2

Describe the FETCH part of the FDE cycle.

Answer 2

• Contents of Program Counter/PC transferred to Memory Address Register/MAR.
• Address bus used to transfer this address to main memory.
• Fetched value/instruction transferred back using the data bus.
• Contents of addressed memory location loaded into the Memory Buffer Register/MBR.
• Transfer content of Memory Buffer Register/MBR to the Current Instruction Register/CIR.

Question 3

Describe the EXECUTE part of the FDE cycle.

Answer 3

• Reading operand data in to the accumulator from the RAM.
• Performing arithmetic functions on operand data.
• Performing logical functions (conditionals / loops).
• Writing data from the accumulator to the RAM.