Portable communication device and system using the portable communication device and attachment for a portable communication device

摘要

A portable communication device is used in a digital money system so as to pay for purchase by digital money by using the portable communication device. A remote communication interface interfaces radio-frequency communication with a remote communication terminal. A short-distance communication interface interfaces wireless communication with a communication terminal located in the vicinity of the portable communication device. Data or instruction information is input to the portable communication terminal by an inputting unit such as a key panel. The data is stored in a memory and is displayed on a display unit such as an LCD. An enciphering and deciphering circuit enciphers or deciphers the data to be transmitted or received so as to maintain security.