Test by Bikram | Computer Organization and Architecture | Test 2 | Question: 5

Question

Using Booth’s algorithm for multiplication the multiplier $(- 37)$ will be recorded as:

• A. $ -1 +1 0 -1 +1 0 -1$
• B. $0  +1 0 -1 +1 0 -1$
• C. $ – 1  0  +1 -1 +1 0 -1$
• D. $+1 \ 0 \  0  -1  +1 0 -1$

Answer 1

37 in base 2 is: $0100101$

-37 will be: 2s complement of 37, i.e. $1011011$.

When encoding for Booth multiplication, we have $+1$ for every $...01...$ pair and $-1$ for every $...10...$ pair. And there is an implied $0$ in the left of LSB.

So, we get the following recording:

-1 +1 0 -1 + 1 0 -1

option (A)