Abstract: A wireless telephone system provides telecommunications services for personal wireless telephone sets over an area which is divided into service cells. Each of the cells is defined by reception characteristics of a plurality of radio base stations within the cell. The telephone system includes a service controller and a port being wireline connected between each radio base station and the service controller. The service controller selects radio base stations for setting up radio links with wireless sets of calling or called persons. A base station which serves a wireless set and surrounding idle base stations monitor strengths of radio signals received from the wireless set and report running averages of the monitored signal strengths to the service controller. Movement of the wireless set from one cell to another cell during a call is detected as a drop in the running average reported by the serving base station.

Abstract: A semiconductor integrated circuit device includes an external terminal, an internal logic circuit, and an input/output interface circuit. The input/output interface circuit includes an input circuit, a selection circuit and an output circuit. The input circuit receives an input signal and supplies the internal logic circuit with the same. The selection circuit selects either the input signal supplied from the input circuit or an output signal supplied from the internal logic circuit. The output circuit outputs the selected one of the input signal and output signal to the external terminal. A loop circuit is formed by the input circuit, selection circuit and output circuit. The loop circuit logically includes an odd number of inverters.