A circuit that adds two 3-bit numbers using a half-adder and a full-adder.

A circuit that takes two decimal numbers A and B as input and then splits in into their corresponding three bits using a splitter and then calculates their summation using XOR, AND and OR gates. This generates 4 output lines for 4 bits of the summation, and a reversed splitter is finally used to join the output lines to produce a 4-bit output and displayed using a Hex-Display. 

This is a ripple-carry adder.