Subscribe to download
Simple binary adder (half adder)

Built using a logical AND gate for the two's place, XOR for the one's place, and a NOR gate for the zero. The AND gate (the 2's place laser) is easy, just connect two buttons to one laser and the laser will only fire if both buttons are pressed. For the XOR gate (1's place), two lasers, each hooked up to one button, are combined and directed to the receiver, flipping on the "1" if one or the other button is pressed, but NOT both (the two lasers on the right side of the map) due to the angled plate that pops up if both buttons (another AND operation) are pressed so that the "1" stays off so the "2" alone can be lit when needed. The 0 laser is lit by default, and by using an OR gate (XOR without the "but not both" part, the two lasers on the left side of the map), it is flipped off if any of the buttons are pressed. This could be used in level design to perform any action given whatever state the two buttons may be in.