Common Computer Science References
Now add a Carry-in to your adder, so it can become a template for a multi-bit adder. Once again you will only be using positive binary numbers, not 2s compliment.
You will now have 3 inputs and 2 outputs. Once again you will have a microcontroller for the inputs to your circuit. Ensure you leave a delay (1 second) between each row in the truth table.