GATE CSE 1996 | Question: 1.22

Question

Number of machine cycles required for RET instruction in 8085 microprocessor is

• A. 1
• B. 2
• C. 3
• D. 5

Answer 1

3 is the answer of this question, 1 cycle for instruction fetch and 2 cycles for stack operations. return address is required to continue with main program after finishing the execution of subroutine.

Answer 2

The RET instruction needs 3 machine cycles. One to fetch and decode the instruction (4 T states), and two more machine cycles (that is, 2*3 = 6 T states) to read two bytes from the stack