Have you ever want a four way switch, but only have one way switches or even only two way switches like this app? It selects from the input(BLUE LED) to output(RED LED). It converts from a selector combination to decimal(simple 1 to 4). It takes the highest input to select one output at a time. Try to hit the switches in order from 1 to 4. The input is "bar coded" and the output is "decimal coded" or "dot coded".
