A printhead including a fluid ejector chip having an electrical interface. The electrical interface includes one or more inputs for receiving respective primitive address data and heater address data corresponding to each of one or more address cycles, at least one of the one or more inputs being switchable to a deactivated state, and one or more shift registers, a total number of shift registers being adjustable so that each of the one or more shift registers corresponds to a respective one of the one or more inputs that is not in a deactivated state, the one or more shift registers receiving the respective primitive address data and heater address data from the one or more inputs that are not in a deactivated state to allow for selective application of electrical signals to the heating elements so that fluid is ejected from the fluid ejector chip in accordance with image data.