4.7.3.4 Fo CompOrgArch (Addressing Modes)

Question 1

What are the 4 memory addressing modes

Answer 1

• Immediate
• Direct
• Indirect
• Indexed

Question 2

What is immediate addressing

Answer 2

• When the absolute value supplied as a part of the operand

Question 3

Explain what ADD 10 does using immediate addressing

Answer 3

Add the value 10 to the value in the Accumulator

Question 4

What is direct memory addressing

Answer 4

• When the absolute value is stored in the memory address specified in the operand

Question 5

Explain what ADD 10 does using direct addressing

Answer 5

Add the value stored in location 10 to the accumulator

Question 6

What is Indirect addressing

Answer 6

When the memory address stored in the operand points to another address that holds the absolute data that is to be added to the accumulator

Question 7

Explain what ADD 10 does using indirect addressing

Answer 7

• Go to the memory address 10 and go to the address specified in 10, then add the value in that memory address to the accumulator

Question 8

What is indexed addressing

Answer 8

The number given in the operand is added to the number in the index register and the number in the summed address is added to the value in the accumulator