A public transportation journey planning system and method provides transit graph data from which routes can be selected using a route searching technique, for vehicle schedules that are not defined in terms of actual arrival and departure times at stations but rather in terms of a repeat schedule having common repeat period for successive vehicles between start and end times of the day. According to one embodiment, an infrared light source is projected across a front surface of a display via at least one light emitting device. The sensing device including directional magnetic field emitters each having a north and a south pole that are spaced from one another along a first pole axis and a second pole axis, respectively. The system then uses this virtual memory address to identify one or more cache lines in the unified cache structure which are associated with the virtual memory address.