Methods and apparatus for improving modularity in a micro-fluid ejection device and for providing instruction data to a plurality of data handling devices within a micro-fluid ejection device. The method includes generating device data and appending an address to the device data to generate instruction data. The address typically indicates at least one data handling device within the micro-fluid ejection device for which the device data is intended. The instruction data is provided to a plurality of data handling devices including at least one data controller. The data controller is operated to decode the address from the instruction data and select at least one data handling device to receive the device data based upon the decoded address. The device data is thereby input into each selected data handling device and subsequently used to operate the micro-fluid ejection device.