Gets the state of a touch button (1) pressed, (0) not pressed. Numbering {6, 5, 4, 3, 2, 1, 0} maps the pads by {OSH, P17, P16, P15, P25, P26, P27}. Example: int state = button(3); If state stores 1, it means the pad next to the P15 label is pressed. If it instead stores 0, the button is not pressed.