[robbrad]

There are different kinds of pressure switches. I'm not sure what "the pressure switch" may refer to. I didn't see one in my kit. The ones I am familiar with change resistence with the load applied, the lower the resistence, the more pressure. I hook up that kind of sensor in series with a 1/4W resistor and measure the voltage accross the sensor pins with ADC. Using the datasheet information about the resistence output, I can determine the load.