This is a 4:1 Multiplexer. The LEDs indicate the state of the inputs and modes.
The first set of LEDs from the bottom right side are the states for the two inputs for mode. Green is HIGH and Red is LOW. The second set of LEDs is for the middle row. These are the states of the four inputs. They are all Blue when HIGH and off when LOW. The last, lone LED at the top is for the multiplexer's output. It is Yellow and indicates a HIGH if lit and a LOW if not.
Have fun exploring with the states of the inputs and the mode inputs. Any feedback is appreciated!
