Question

DAA command adds 6 to the nibble if:

(a) CY and AC are necessarily 1

(b) either CY or AC is 1

(c) no relation with CY or AC

(d) CY is 1

I got this question in an internship interview.

This is a very interesting question from Arithmetic and Logic Instructions in section 8051 Microcontroller of Microcontroller

Answer 1

The correct answer is (b) either CY or AC is 1

To explain: DAA command adds 6 to the nibble if any of the nibbles becomes greater than 9.