**Computer Architechture Question**

In this lab you will design a simple digital circuit called a full adder Background: Adders An adder is a circuit whose output is the binary sum of its nputs A full adder has three inputs (A, B, Cin and two outputs (S, C. as shown in Figure 1. Inputs A and B each represent -bit binary numbers that are being added, and S represents a bit of the resulting sum. Figure 1. Full adder The Cn (carry in) and Cout (carry out) signals are used when adding numbers that are more than one bit long. To understand how these signals are used, consider how you would add the binary numbers 101 and 001 by hand 101 + 001 110 As with decimal addition, you first add the two least significant bits. Since 1+1-10 (in binary), you place a zero in the least significant bit of the sum and carry the 1. Then you add the next two bits with the carry, and place a in the second bit of the sum. Finally, you add the most significant bits (with no carry) and get a 1 in the most significant bit of the sum. When a sum is performed using full adders, each adder handles a single column of the sum. Figure 2 shows how to build a circuit that adds two 3-digit binary numbers using three full adders. The Cou for each bit is connected to the Cin of the next most significant bit. Each bit of the 3-bit numbers being added is connected to the appropriate adder's inputs and the three sum outputs (S2) make up the full 3-bit sum result