Question

What steps are involved when we subtract two numbers present at two different locations?

(a) take the two’s complement of the subtrahend

(b) add it to the minuend

(c) invert the carry

(d) all of the mentioned

The question was asked during an internship interview.

This key question is from Arithmetic and Logic Instructions topic in section AVR Microcontroller of Microcontroller

Answer 1

Correct answer is (d) all of the mentioned

For explanation I would say: When we need to subtract two numbers present at two different locations then firstly we need to take the 2’s complement of the subtrahend, then we add it with the minuend and then when we invert the carry then the complete procedure of the subtraction is completed.