An electronic connector having double inserting interfaces includes a housing, two plugs, a connecting unit and a linking element. Prior to the detection of the mark, a reference received light quantity level is sampled for the surface of an object not including the mark, for every color of light. After a protection switch, a slower tuning algorithm is used to adjust the decision threshold to a more optimum value. The sensor is fixedly attached to the bicycle brake at a location to detect rotational behavior of a bicycle wheel by sensing the magnet mounted to the air valve stem. The graphics processing unit operates on the data structures read from the separate buffer with the operation. The aspects include forming a database of font specifications.