Patent ID: 7463838

Claim:
A replaceable consumable for use in an associated printing device to form marks on an associated substrate, the replaceable consumable comprising: a cartridge body configured for operative connection with said associated printing device; a marking material contained in said cartridge body, the marking material being selectively delivered to the printing device from said cartridge body to form said marks on said substrate; a memory element coupled with the cartridge body, the memory element holding data relating to said marking material including marking material quantity data Q C representative of a quantity of said marking material in said cartridge body; and, an electronic member operatively associated with said memory element, the electronic member being responsive to read signals from the associated printing device during a read sequence to deliver said marking material quantity data Q C from said memory element to said associated printing device, and being responsive to write signals from the associated printing device during a write sequence to receive revised marking material quantity data Q P from the associated printing device, the electronic member being operative in first and second operational modes during said write sequence to selectively i) replace said marking material quantity data Q C with said revised marking material quantity data Q P as new marking material data Q NEW in said first operational mode according to Q NEW =Q C ←Q P and ii) replace said marking material quantity data Q C with a modified revised marking material quantity data Q P ′ as said new marking material data Q NEW in said second operational mode according to Q NEW =Q C ←Q P ′, where Q P ′≠Q P .