The button on the ProtoShield is 'pulled high', meaning one side of the button is

connected, through a resistor, to +5V and also to 'JC1' (which should then be

connected to an Arduino pin of your choice). The other end of the button is simply

connected to ground. This means that when the button is pressed it will read as

LOW, otherwise it will be HIGH. In the example above, the LED will be on unless the

button is being pressed.

Using the BlueSMiRF port

Bluetooth is a really simple, and effective way to add wireless communication to your

project. The BlueSMiRF Gold works as, essentially, a serial cable minus the wires.

Only four connections are required to communicate with the BlueSMiRF - 5V, GND,

RX and TX.

When you connect the BlueSMiRF to your ProtoShield, take care to match the 'VCC',

'GND', 'TX-O', and 'RX-I' labels of the BlueSMiRF with the '5V', 'GND', 'D0', and 'D1'

labels of the shield.