CSE-45208 Lab #8 Adder / Subtractor Dr. Izadi

1. Go through the Xilinx tutorial .

2. Using Xilinx tools, design and implement a four-bit adder / subtractor circuit as indicated below.

• Label one set of inputs as A₃A₂A₁A₀ and the other set as B₃B₂B₁B₀.
• Label the outputs as S₃S₂S₁S_0.
• Additional input X selects the circuit function.

X=0: S₃S₂S₁S₀ = A₃A₂A₁A₀ + B₃B₂B₁B₀

X=1: S₃S₂S₁S₀ = A₃A₂A₁A₀ - B₃B₂B₁B₀

Verify the circuit and have it signed by your instructor or TA.

3. Additional tutorial is available in the lab web site.