In a display device, a display surface portion includes a light emitting area on which a plurality of light emitting devices are arranged, and a nonluminous area formed on spaces among the arranged light emitting devices on the display surface portion. This avoids complications that can arise due to the packet data service being discontinued upon registration and the resulting inability to reach the mobile station. Because such a selector can automatically direct the processor to the appropriate firmware when the computer stores multiple firmware, the selector allows a customer to change the processor without requiring him to change the firmware memory or the board on which the firmware memory resides. A ribbon of conductive material may be interposed between each of the bus bars and the heater. At least one counter areaelement is provided.