Question

What is the use of the MSBFIRST argument in the shiftIn() function?

(a) To denote the least significant bit

(b) To denote the maximum number of Bits

(c) To denote the most significant bit

(d) To denote the minimum number of bits

I got this question in an internship interview.

Question is taken from Advanced Input Output topic in chapter Arduino Programming of Arduino

Answer 1

Correct answer is (c) To denote the most significant bit

To explain I would say: The shiftIn() function shifts in one byte of a binary number bit by bit starting from either the most significant bit or the least significant bit. Now after each bit is pulled, the clock pin is turned to HIGH until the next one at which point the clock pin is turned down to LOW again. Now the MSBFIRST argument denotes that the byte of data be read from left to right.