Abstract: A battery management circuit allows a communication circuit to communicate with a CPU of an intelligent battery. The communication circuit serves to obtain a battery information signal from the CPU. A battery controlling circuit is allowed to control the supply of the electric power from the intelligent battery in view of the battery information, such as the electric power remaining in the battery, the voltage level of the supplied electric power. When a deficiency is found in the battery information signal, the battery controlling circuit switches over the supply and cutoff of the electric power based on the voltage level detected at a voltage detector circuit. The supply of the electric power can be controlled without the battery information signal. Even when the defect is found in the battery information signal, the supply of the electric power can be maintained as long as the voltage level is normal. The interruption of related operations can be deferred.

Abstract: In a portable terminal apparatus, character information corresponding to map information of destination is displayed or updated. The information such as the map information of destination is entered from an information input unit employed in the portable terminal apparatus, and a display sequence is determined by a display sequence determining unit. A position of destination is set by using a pen and the like by the portable terminal apparatus. The set position data is transferred to a host computer so as to update map data stored in the host computer. With the execution of the above-described operations, operability of the portable terminal apparatus can be improved, and the customer can be quickly and surely managed.