US Patent 7551859 Multiple region printer chip

A toner cartridge having a microcontroller configured to store data necessary to create a message authentication code required by the printer. The microcontroller contains data values capable of generating acceptable MACs for a plurality of printers used in a plurality of geographic regions. The microcontroller recognizes a variety of unique parameters displayed by the printer's processor to identify the geographic region of the printer being used. Once the printer and geographic region are identified, the microcontroller loads the data values associated with the printer and generates an acceptable MAC to enable printer operation.