PURPOSE: To enable printing and copying of a document to be performed by only a printer device without connection to a host device by storing online data into a memory card detachably fitted to a main body of the printer device, as a copy of printing data.

CONSTITUTION: In response to an instruction from a host device, printing data is inputted to a printer device through a data receiving circuit 7 as online data, and is sent to a printing controlling circuit 8, to be printed by a printing mechanism part 9. The same printing data as above is stored into a data memory 17 in a memory card 16 connected directly to a bus line of the printer device, through a data writing circuit 14. When an instruction for starting printing is supplied from a copying instructing part 11, a copy counter 12 counts the number of times of copying. Simultaneously, a copy printing circuit 13 is operated, and a data reading circuit 15 reads the data stored in the data memory 17 in the memory card 16. The data thus read is printed through the printing controlling circuit 18 and the printing mechanism part 19. This operation is repeated the number of times set on the copy counter 12.