Abstract: A level convertor is provided between circuits, which act with different power supply voltages, respectively, and converts a first voltage level of an output of a circuit to a second voltage level, which corresponds to an operational voltage level of another circuit. The level convertor comprises a level shift circuit, which receives the first voltage level and outputs an output of the second voltage level, and a buffer circuit, which receives the output of the second level and a control signal, and fixes the output of the second voltage level to a low logic level, when the control signal is a low logic level. The control signal may be used to set a timing for registering the data to a register, avoiding data in an instable state when power is supplied, from being registered to the register.

Abstract: A system includes a portable remote terminal for communicating with other terminal devices and an external unit for inputting information. The portable remote terminal has a connector for connecting the portable remote terminal to the external unit, a flash memory for storing information used in the portable remote terminal, a debugging tool area provided with the flash memory, the debugging tool area storing a program in accordance with which the information stored in the flash memory is rewritten, and a controller for rewriting the information stored in the flash memory so as to be information, input by the external unit and supplied from the external unit via the connector, the rewriting being in accordance with the program stored in the debugging tool area of the flash memory.