datapath components

Question 1

explain the process of adding in binary

Answer 1

binary adders calculate adding binary numbers from left to right. you add the 0s and the 1s and carry the one to the next column if you end up with a two digit number.

Question 2

what is 0111 + 0010?

Answer 2

1001

Question 3

what is the difference between an adder and a carry-ripple adder?

Answer 3

an adder computes A+B where A & B are N-bit numbers (such as 8-bit numbers). a carry ripple adder mimics adding by hand with carry signals.

Question 4

what is the difference between a half adder and a full adder

Answer 4

A full adder adds 3 bits and generates a sum and a carry-out bit. a half adder adds two bits and can generate a sum and a carry out, but only a full adder can be designed starting from a truth table.

Question 5

what do unsigned/signed numbers refer to?

Answer 5

signed involve positive and negative integers, but unsigned only includes positive numbers.

Question 6

in singed magnitude representation what do 0 and 1 mean?

Answer 6

focus on the very left bit. 0 means positive, 1 means negative

Question 7

explain two’s complement representation

Answer 7

invert every bit and add one. for example, 0011 will be 1100 + 1 which is 1101. 1101 now represents a negative number of whatever value it refers to (-5)