The present invention allows a printing process to be released from application software earlier. At the start of printing, the size of an available area in a RAM 11 is obtained. It is determined whether or not the size of total print data transmitted from a handheld computer to a color printer is the obtained size of the available area. If it is determined that the size of the total print data is larger, the size of an available area in a memory card is obtained. It is then determined whether or not the obtained size of the available area is larger than the size of the total print data. If it is determined that the size of the available area is larger, the total print data is created on the available area in the memory card. Then, the created total print data is transmitted to the color printer.