Patent ID: 7843585

Claim:
An interface module adapted to be connected to two or more host devices each of said host devices capable of generating print data, and to a printing device that is capable of printing the print data, comprising: a reception unit having at least two interfaces each for connection to a host device and for receiving print data from a connected host device; a parameter data acquisition unit for analyzing the received print data and acquiring parameter data from the received print data for calculating a printing cost incurred by printing the received print data; a parameter data storage unit that stores the acquired parameter data separately for each of a plurality of predetermined categories and separately for each of the at least two interfaces; and a printing cost calculation unit that calculates the printing cost for each of the plurality of predetermined categories and for each of the at least two interfaces based on the stored parameter data; wherein the parameter data is stored when the printing cost calculation unit finishes calculating the printing cost, and the difference between the stored parameter data and current parameter data is used in the printing cost calculation unit.