Question

The step involved in POP operation is

(a) decrement stack by 2 and store 8-bit content to address pointed to by SP

(b) store 16-bit content to address pointed to by SP and decrement stack by 1

(c) decrement stack by 1 and store content of top of stack to address pointed to by SP

(d) store content of top of stack to address pointed to by SP and then decrement stack by 1

This question was posed to me during an interview for a job.

I want to ask this question from Interrupt and Stack of 8051 topic in division Microcontroller 8051 of Microprocessor

Answer 1

Correct choice is (d) store content of top of stack to address pointed to by SP and then decrement stack by 1

Explanation: The POP instruction follows two steps.

1. Store the contents of top of stack pointed to by SP register to the 8-bit memory specified in the instruction.

2. Decrement stack by 1.