A method of operating a plurality of driving units for powering electronic units is described. The method includes interchanging a data frame including a bit sequence, between a master control unit and at least one of a plurality of driving units at slave nodes. The method includes applying an ID field for addressing at least one driving unit, and applying a data field comprising information and/or instructions regarding the status of the electronic units. Applying the ID field comprises indicating the driving unit address using a first bit sub-string comprising N bits, allowing the master control unit to identify whether data should be received or transmitted, performing a data length decoding step, and adding a further bit string to the data field including information for carrying out an action by the driving unit.