Patent ID: 8022317

Claim:
A digitizer controller comprising: a memory for storing a plurality of respective different position indicator calibration data, each associated with a respective type of position indicator, each respective type of position indicator having a respective inductive signature within a respective operating frequency band; a survey module configured to control a digitizer to survey for presence, adjacent to a working surface of the digitizer, of different types of position indicators defined by the plurality of position indicator calibration data; and a position sensing module configured to control the digitizer to track the position of an identified position indicator identified by the survey module as being adjacent to the working surface of the digitizer, in accordance with the position indicator calibration data associated with the identified position indicator; wherein the respective operating frequency bands of different types of position indicators overlap with each other and wherein the survey module is configured to distinguish between position indicators having similar inductive signatures with overlapping operating frequency bands by surveying for the different types of position indicator in accordance with a selected order and not based on operating frequencies of the position indicators.