To effectively improve operablity and cost performance in equipment such as an adapter to be connected to a portable telephone by converting data into push button signals and transmitting the signals to a server or the like, thereby remarkably generalizing equipment and programs regardless of the carrier and model of the portable telephone.

A data converting part C performs a data transmission by sending a dial operation command code train for generating a push button signal train converted of transmission data to the portable telephone K as a converting and transmitting means. More concretely, the data converting part C converts (maps) the transmission data into the push button signal, that is, a string of a DTMF (dial tone multi frequency) on the basis of a predetermined conversion rule and transmits the string of the DTMF signal to a server S of a communication destination through a plug F and the portable telephone K.