A system and method for providing a dedicated digital interface between multiple graphics devices. The organic light emitting display device includes a pixel region having a plurality of organic light emitting diodes; a power bus line that is located on an outer side of the pixel region and supplies power to each of the organic light emitting diodes; and a metal layer that overlaps the driving power bus line, is electrically connected to the driving power bus line, and comprises a panel mark. In some embodiments, a set of data is encoded based at least in part upon the states of multiple decoders to which the encoded set of data is to be provided. The attachment and construction further allows easy removal and replacement of filter media and cartridges. A detector utilizes the time between receipt of the RF signal and the slower-traveling audio signal to determine the distance between the detector and the simulated grenade.