To reliably and quickly carry out command analysis processing while effectively utilizing a limited memory resource.

When a print control command received from a host computer 11 is to be deployed on a work memory 36, analyzed, and subjected to printing, the type of the received print control command is determined. Based on the corresponding relation of the type of the print control command stored in advance and the capacity of the memory area to be ensured in the memory for the command analysis processing, an area 36A for the command analysis processing having a predetermined capacity corresponding to the type of the print control command is ensured in the work memory 36.