A data communication system and method in which a need to store a frame count value in a non-volatile memory and update the frame count value is obviated, and in which the effect resulting when a frame with its frame count value altered to a value close to a full count value is transmitted is reduced. The tip is located at the distal end of the device and provides for tissue dilation upon entry of the device into the body of a patient. The method includes receiving a Diameter request message. For instance, Inconel\u2122 625, Inconel\u2122 601 or Hastelloy\xae may comprise the ionization chamber or the surface walls of the ionization chamber. The anode of the display is coupled to a power supply adapted to couple either a relatively high voltage to the anode when such display is to operate in a relatively bright environment or a relatively low voltage when such display is to operate with relatively dim environment.