Build a 2 bit adder. A two-bit adder is one that can add numbers consisting of 2-bits, i.e. 112. 1. Create a part for the Full-Adder. You will need to ensure that you replace the DigiStim inputs on the previous design with ports. If you do not your design will not work right. 2. Use your newly created part to create a 2 bit adder. This is an adder which adds 2 2-bit numbers. 3.