A printhead IC for an inkjet printer, the inkjet printer having a print engine controller (PEC) for sending print data to the printhead IC, the printhead IC comprising: an array of nozzles for ejecting drops of printing fluid onto a media substrate; and, drive circuitry for driving the array of nozzles, the drive circuitry being configured for connection to a power source in the printer; wherein, the drive circuitry being configured to reset itself to a known initial state in response to receiving power from the power source after a period of not receiving power from the power source.