If a positive judgment is made at Step S82, the control goes to Step S88 to judge whether the FAX 2 has received call-transmit command data ATD+STRING. Since the PC 4 has transmitted call-transmit command data to the FAX 2, a positive judgment is made at Step S88, and the control goes to Step S89 to terminate the dialing operation and set a flag corresponding to the sort of data to be transmitted,