Question

To detect that in which column, the key is placed?

(a) we can mask the bits and then check it

(b) we can rotate the bits and then check that particular bit which is set or reset(according to the particular condition)

(c) none of the mentioned

(d) all of the mentioned

This question was addressed to me in an interview for job.

The question is from Keyboard Interfacing in section 8051 Microcontroller of Microcontroller

Answer 1

The correct answer is (d) all of the mentioned

The explanation is: We can mask or we can even rotate the bits to check that particularly in which column is the key placed.