A method of operating a plurality of driving units for powering electronic units, the method comprising 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 sequence being divided in fields of consecutive bit strings, the method comprising: - applying an ID field for addressing at least one driving unit, for interchanging data between the master control unit and the at least one addressed driving unit, - applying a data field (DATA) comprising information and/or instructions regarding the status of the electronic units of said addressed at least one driving unit, characterized in that applying the ID field further comprises: - indicating the driving unit address using a first bit sub-string (ID15-ID10) comprising N bits, where 2^N is equal or higher than the number of driving units in the plurality of driving units, for applying the data field on the addressed driving unit or ignoring the data field if the driving unit is not addressed - using a receive/transmit (R/T) command bit for assigning values, for allowing the master control unit to identify whether data should be received from or transmitted to driving units, or for allowing each addressed driving unit to decode which action is required by the master control unit depending on the value assigned to the receive/transmit (R/T) command bit, - using a further function bit including information in the ID field regarding the type of information and/or instructions included in the data field, - depending on the value assigned to the function bit, assigning, in a second bit sub-string (ID7-ID2) of the ID field, data bits in the data field to different electronic units of the addressed at least one driving unit or performing a length decoding step for indicating the length of the bit string in the data field using that second bit sub-string (ID7-ID2). - applying an ID field for addressing at least one driving unit, for interchanging data between the master control unit and the at least one addressed driving unit, - applying a data field (DATA) comprising information and/or instructions regarding the status of the electronic units of said addressed at least one driving unit, characterized in that applying the ID field further comprises: - indicating the driving unit address using a first bit sub-string (ID15-ID10) comprising N bits, where 2^N is equal or higher than the number of driving units in the plurality of driving units, for applying the data field on the addressed driving unit or ignoring the data field if the driving unit is not addressed - using a receive/transmit (R/T) command bit for assigning values, for allowing the master control unit to identify whether data should be received from or transmitted to driving units, or for allowing each addressed driving unit to decode which action is required by the master control unit depending on the value assigned to the receive/transmit (R/T) command bit, - using a further function bit including information in the ID field regarding the type of information and/or instructions included in the data field, - depending on the value assigned to the function bit, assigning, in a second bit sub-string (ID7-ID2) of the ID field, data bits in the data field to different electronic units of the addressed at least one driving unit or performing a length decoding step for indicating the length of the bit string in the data field using that second bit sub-string (ID7-ID2).