Patent ID: 8449054

Claim:
An ink jet printer comprising: an ink cartridge receiving portion arranged to receive an ink cartridge and to allow passage of ink from a received ink cartridge to printing fluid conduits of the ink jet printer; a solvent cartridge receiving portion arranged to receive a solvent cartridge and to allow passage of solvent from a received solvent cartridge to printing fluid conduits of the ink jet printer; a data reader arranged to read data indicating a quantity of fluid within a received ink cartridge from an electronic data storage device associated with the received ink cartridge and arranged to read data indicating a quantity of fluid within a received solvent cartridge from an electronic data storage device associated with the received solvent cartridge; an ink supply system comprising a mixer tank in communication with said ink cartridge and said solvent cartridge; an electronic data storage device associated with the ink supply system; and a controller arranged to communicate with the electronic storage devices of the ink cartridge, the solvent cartridge, and the ink supply system, the controller further arranged to generate update data usable to modify data stored on each of said ink and solvent electronic data storage devices and to modify data stored on each of said ink and solvent electronic storage devices based upon said update data such that data stored on each of said ink and solvent electronic data storage devices indicates an updated quantity of fluid in each of said ink and solvent cartridges, wherein said controller is further arranged to determine a quantity of fluid within each of said ink and solvent cartridges based upon at least one property of fluid within each of said ink and solvent cartridges and to generate said update data based upon said determination; wherein said ink jet printer is a continuous ink jet printer.