A method of operating a plurality of driving units for powering electronic units, the method comprising interchanging a frame including a bit sequence between a master control unit and at least one of a plurality of driving units, 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 comprising a payload including information and/or instructions regarding the status of the electronic units of said addressed at least one driving unit, wherein applying the ID field further comprises - indicating the driving unit address using a first substring of bits (ID15-ID8) 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 at least one addressed driving unit, and ignoring the DATA field if the driving unit is not addressed, - using a receive/transmit command bit (R/T) for assigning values, for allowing the master control unit to identify whether data should be received from or transmitted to the at least one addressed driving unit, and for allowing each addressed driving unit to decode which action is required by the master control unit when the frame is received by the at least one addressed driving unit, depending on the value assigned to the receive/transmit command bit (R/T), - indicating the length of the payload using a second substring (ID4-ID2) in the ID field, - further using an instruction bit for assigning values, indicating the type of information in the DATA field, characterised in that applying the DATA field further comprises: - applying a sequence of bits consisting of the sequence of bits of the payload, if the instruction bit has a first value, and - applying a sequence of bits comprising the sequence of bits of the payload and at least one additional bit substring at a pre-defined position in the DATA field, the additional bit substring introducing information for carrying out an action by the driving unit, if the instruction bit has a second value different from the first. - 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 comprising a payload including information and/or instructions regarding the status of the electronic units of said addressed at least one driving unit, - indicating the driving unit address using a first substring of bits (ID15-ID8) 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 at least one addressed driving unit, and ignoring the DATA field if the driving unit is not addressed, - using a receive/transmit command bit (R/T) for assigning values, for allowing the master control unit to identify whether data should be received from or transmitted to the at least one addressed driving unit, and for allowing each addressed driving unit to decode which action is required by the master control unit when the frame is received by the at least one addressed driving unit, depending on the value assigned to the receive/transmit command bit (R/T), - indicating the length of the payload using a second substring (ID4-ID2) in the ID field, - further using an instruction bit for assigning values, indicating the type of information in the DATA field, - applying a sequence of bits consisting of the sequence of bits of the payload, if the instruction bit has a first value, and - applying a sequence of bits comprising the sequence of bits of the payload and at least one additional bit substring at a pre-defined position in the DATA field, the additional bit substring introducing information for carrying out an action by the driving unit, if the instruction bit has a second value different from the first.