1. A method comprising: at a processing device that is electrically coupled to a touchscreen device via a plurality of sensor electrode pins and an identification pin, wherein the touchscreen device includes a plurality of sensor electrodes in a sensor array and a component external to the sensor array, and each of the plurality of sensor electrode pins is electrically coupled to at least one respective sensor electrode of the plurality of sensor electrodes: electrically coupling to the component via one of the plurality of sensor electrode pins and the identification pin, wherein the component shares access to the one of the plurality of sensor electrode pins with a subset of sensor electrodes; measuring an electrical characteristic of the component of the touchscreen device; and identifying, by the processing device, a set of parameters for operating the touchscreen device based on the electrical characteristic.