Question $6-$ Averages with MCU Arithmetic $(10$ pts$)$

MSP$430$FR$6989$ has instructions to add, subtract, and perform arithmetic bit$-$shifting,

but no instructions to divide or multiply. Using this MCU you want to find the average

value of the set of decimal numbers $\{2,-47,13,11\}.$ Assume $8-$bit registers and twos

complement notation for signed numbers.

First devise a scheme of how you can find the average of these numbers using $8-$bit

signed numbers and the given operations $($pairwise addition, subtraction, and bit$-$

shifting$).$ Then answer following questions:

$($a$)$ What is the result in bits as it is stored in an $8-$bit register? Enter a binary number.

$($b$)$ What is the corresponding value? Enter a decimal number.

Hint: There are two ways to solve this problem: like a dumb MCU $($adding$/$shifting bit by

bit$)$ or like a smart human $($understanding the limits of $8-$bit binary arithmetic and when

they apply $-$ they do not apply in all cases$).$