Patent ID: 7620728

Claim:
A method of monitoring the communication in a group of data processing units that are interconnected via a data bus, wherein a data processing unit of the group of data processing units transmits data signals to each of the other data processing units in the group for carrying out certain operations, the data processing unit in the group that transmits the data signals being the transmitting data processing unit and the remaining data processing units in the group being the other data processing units, the method comprising: upon reception of a data signal from the transmitting data processing unit, each of the other data processing units in the group answers both the transmitting data processing unit and each of the other data processing units except itself by way of an appropriate acknowledgement of receipt of the data signal, which is sent back to the transmitting data processing unit and to each of the other data processing units in the group except itself; wherein each of the other data processing units in the group generates a status signal of its own that contains at least its own acknowledgement; and wherein each of the other data processing units in the group answers in a chronologically defined sequence, as a result of which at least a first data processing unit of the other data processing units in the group and subsequently a next, second data processing unit of the other data processing units in the group, answer both the transmitting data processing unit and each of the other data processing units in the group except itself, where the first data processing unit transmits as its answer a status signal that contains only its own acknowledgement, the second data processing unit transmits as its answer a status signal that contains its own acknowledgement and, besides, also the acknowledgement of the first data processing unit; and, if applicable, every further data processing unit of the other data processing units in the group that answers next, transmits as its answer a status signal that contains its own acknowledgement and, besides, also the acknowledgements of each of the other data processing units in the group that have answered previously; wherein the status signals generated by each of the other data processing units in the group have the same number of signal elements, wherein the number of signal elements in each of the status signals corresponds to the number of the other data processing units in the group, each signal element being associated with a specific data processing unit of the other data processing units in the group and indicating the acknowledgement thereof.