Digital Sensors
Digital sensors are switches, they only know two values: on and off.
Most of fischertechnik digital sensors have to pins. These need to be connected to the controllers input pins. Some sensors have a red marked pin. Connect the marked pin to the red cable at ftSwarm/ftSwarmControl, use the signal input pin at ftSwarmRS.
Check ftSwarm and ftSwarmControl pinouts for more details.
Image source: fischertechnik & elektrofuzzis