Abstract: A receiver side of a two-wire type remote control system accurately determines the polarity of data. The reception buffer inverts an input from one of the data and electric communication lines, and adds the inverted input to an input of the other line. Then, when the result of the addition is 0 or close to 0, the reception switches buffer logic data to be output to indicate the inversion of the level of the equilibrium pulse-like power received from the communication lines. The polarity identifying portion identifies the polarity when the logical data sent from the reception buffer is maintained at a logic level for a predetermined period of time. The polarity identifying portion sends pulse group data to the data processing portion in accordance with the identified polarity.

Abstract: The wiring case has a detachable display device for displaying contents of data and electric transmission/reception communications established with a predetermined controlling device. In the display device, a pair of wiring members are prepared. The tip end portions of the wiring members are directed towards the bottom surface portion of the wiring case, and the each tip end portion has a contact point. The wiring case has an opening at a section opposing to the bottom surface portion, and a stopper portion is formed at end portion of each of sidewalls of the long-scale box.