The schematic for the mouse trap used a serial interface with the A3BU in the form of a MAX232 IC. This was the same configuration used in a previous lab. The part we had to design and figure out was the four photoresistors that were set in the mouse trap. We accomplished this by hooking a 10K ohm resistor in series with two of the photoresistors and a 1 micro farad capacitor. This way when the photoresistors are blocked (meaning no light getting to them) the RC constant was about a second for the capacitor to fully charge. This then allowed us to code the correct trip times for the servo to trigger releasing the bar on the mouse trap. The servo was hooked up from a ground source, a 3.3V power source, and the SCL pin on the J1 header of the A3BU. This gave us our PWM that was needed to move the servo in the correct manner. Lastly we had a wire soldered to the mouse trap as well as one wrapping around the front of the mouse trap. These wires were then connected to a 220 Ohm resistor and a LED. When the circuit was complete the LED would light up indicating that nothing was caught and the trap needed to be reset.