Operation of a bus network, in particular reconfiguration in the event of a fault

Abstract

The invention relates to a method for operating a bus network (1), comprising a bus controller (2) and a plurality of bus operating devices (3 to 8) which are intercoupled by means of a network line (9), wherein: the bus controller transmits a request signal (22) to the bus operating devices; the bus operating devices successively transmit to the bus controller, via the network line, respective device data relating to the bus operating devices at a specified position (23 to 28) in a specified transmission sequence (14); the bus controller receives the device data and, depending on the position in the transmission sequence, assigns each piece of received device data to one of the bus operating devices. According to the invention: the bus controller sends to the bus operating devices an identification data request signal for the transmission of individual identification data in the bus operating devices; the bus operating devices transmit their respective individual identification data to the bus controller according to the specified transmission sequence; the bus controller receives the identification data, assigns each piece of identification data to the particular bus operating device depending on a position in the specified transmission sequence, and stores each piece of identification data with the particular position.

Description

[0001] Operating a BUS network, especially reconfiguration in the event of a fault

[0002] The invention relates to a method for operating a BUS network, having a BUS control unit and a plurality of BUS operating devices that are coupled to one another via a network line of the BUS network, wherein the BUS network is operated according to a daisy chain method, in which the BUS control unit sends a query signal to the BUS operating devices via the network line, the BUS operating devices receive the query signal and sequentially send respective device data from the BUS operating devices at a predetermined position in a predetermined transmission sequence via the network line to the BUS control unit, the BUS control unit receives the device data and, depending on the position in the transmission sequence, assigns the respective received device data to a respective one of the BUS operating devices. The invention further relates to a computer program product and a computer-readable data carrier.Finally, the invention also relates to a BUS control device for a BUS network, wherein the BUS network has, in addition to the BUS control device, a plurality of BUS operating devices which are coupled to one another by means of a network line of the BUS network, wherein the BUS network is operated according to a daisy chain method, wherein the BUS control device is designed to send a query signal to the BUS operating devices via the network line, to receive respective device data of the BUS operating devices which the BUS operating devices send successively to the BUS control device via the network line in response to the query signal at a predetermined position in a predetermined transmission sequence, and to assign the respective received device data to a respective one of the BUS operating devices depending on the position in the transmission sequence.

[0003] Generic methods, BUS control units therefor, computer program products, and computer-readable data storage devices are fundamentally well known in the prior art, so that separate written documentation is not required. BUS networks serve to couple and operate BUS operating devices connected via the network cable to the BUS control unit, for example, by transmitting data, in particular device data, from the BUS operating devices to the BUS control unit, transmitting control commands from the BUS control unit to one or more of the BUS operating devices, and / or the like. BUS operating devices can be, for example, sensors, actuators, combinations thereof, or the like. The device data can therefore include, for example, recorded values ​​from the sensors, operating states of the BUS operating devices, combinations thereof, and the like.

[0004] The BUS operating devices are often connected to the BUS control unit via a network cable and can exchange data via the network cable. Among other things, the network cable therefore serves for communication between the BUS control unit and the BUS operating devices. Furthermore, the network cable can also be used to supply power to the BUS operating devices. The network cable can, for example, be designed as a two-wire cable. Depending on requirements, the network cable can of course also have more than two individual lines of a two-wire cable. The BUS network can be operated based on a bus protocol, such as the Distributed Systems Interface (DSI). One such protocol is disclosed, for example, in the DSI3 bus standard dated February 16, 2011.

[0005] In a daisy-chain process, as disclosed, for example, in the DSI3 Bus Standard of February 16, 2011, the BUS operating devices are generally serially linked to the BUS control unit via the network cable. It is therefore important that the BUS operating devices do not attempt to transmit their device data over the network cable in response to a query signal from the BUS control unit at different times. For this reason, the daisy-chain process provides for the BUS operating devices to transmit their respective device data in response to the query signal from the BUS control unit at a respective assigned position in a predetermined transmission sequence. The position in the transmission sequence is assigned to the respective BUS operating device. This provides a respective time window for transmitting the device data, which is individually assigned to the respective BUS operating device.The transmission order can be defined, for example, during initialization or configuration of the BUS network. As a rule, the transmission order remains essentially unchanged during normal operation of the BUS network.

[0006] The BUS control unit can assign the respective device data to the respective BUS operating device based on the transmission sequence of the device data and the assigned positions in the transmission sequence, which are individually assigned to the respective BUS operating devices. The device data can then be made available for further processing. The processing can take place at least partially in the BUS control unit, or it can also be provided that the device data is transmitted to a higher-level controller for further processing. In the latter case, based on the assignment of the position in the transmission sequence, it can of course also be provided that the device data is assigned to the respective BUS operating devices and transmitted to a higher-level controller.

[0007] The increasing use of sensors and actuators in applications such as motor vehicles has led to the use of bus networks in motor vehicles as well. Sensors, actuators, and / or similar devices can be implemented as bus operating devices that are connected to the bus control unit via the network cable.

[0008] Particularly when the motor vehicle has driver assistance and / or can be driven at least partially autonomously, it is necessary to achieve a high level of reliability in the intended operation of the BUS network, particularly with regard to communication. Nevertheless, it has been shown that if a fault occurs, for example an interruption in the network line, one or more defects or malfunctions in the BUS control units, or the like, communication can be disrupted in the prior art. This is disadvantageous for BUS operating devices that are at least partially responsible for the safety of a system such as the motor vehicle. It proves to be particularly disadvantageous if a BUS operating device is faulty and no longer responds in the transmission sequence. The transmission positions of the subsequent BUS operating devices can then shift from the perspective of the BUS control unit without the BUS control unit noticing.This can cause the BUS network to fail, at least partially.

[0009] The invention is based on the object of improving the reliability of the intended operation of a BUS network.

[0010] As a solution, the invention proposes a method, a computer program product, a computer-readable data carrier and a BUS control device according to the independent claims.

[0011] Advantageous further training results from features of the dependent claims.

[0012] With regard to a generic method, the invention proposes in particular that the BUS control device sends an identification data query signal for transmitting individual identification data stored in the BUS operating devices in a readable manner to the BUS operating devices, the BUS operating devices receive the identification data query signal, the BUS operating devices send their respective individual identification data to the BUS control device in accordance with the predetermined transmission sequence, the BUS control device receives the individual identification data, assigns the respective identification data to the respective BUS operating device depending on a position in the predetermined transmission sequence, and stores the respective identification data with the respective position assigned to the respective identification data.

[0013] With regard to a computer program product, the invention proposes in particular that the computer program product has program code means which are stored in particular in a computer-readable medium in order to at least partially carry out the method for operating a BUS network according to the invention when the computer program product is processed on a computer unit of a BUS control device of the BUS network.

[0014] With regard to a computer-readable data carrier, the invention proposes in particular that the computer-readable data carrier has program code instructions which, when executed by a computer unit, cause the computer unit to at least partially carry out the method for operating a BUS network according to the invention.

[0015] With regard to a generic BUS control device, the invention proposes in particular that the BUS control device is further designed to transmit an identification data query signal for transmitting individual identification data stored in the BUS operating devices in a readable manner to the BUS operating devices, to receive, in response to the identification data query signal, respective individual identification data sent from the BUS operating devices to the BUS control device in accordance with the predetermined transmission sequence, to assign the respective identification data to the respective BUS operating device depending on a position in the predetermined transmission sequence, and to store the respective identification data with the respective position which is assigned to the respective identification data.

[0016] The invention is based, among other things, on the idea that value pairs, each comprising at least the identification data and the current position in the transmission sequence, are stored. For this purpose, the BUS control unit can have a memory unit in which the value pairs can be stored. In principle, the value pairs can also be stored, at least in part, in an external memory unit that has a communication link with the BUS control unit. It is therefore possible for the BUS control unit or the higher-level controller to determine which BUS operating devices are active. The data can also be used for further processing of the device data that is transmitted to the BUS control unit in response to a query signal. It is therefore possible to identify individual BUS operating devices within the framework of the daisy chain process.This can also be useful, among other things, if one of the bus operating devices is being serviced or replaced and the functionality, particularly with regard to the device data, changes after the service or replacement. This makes it possible to improve the overall reliability of the bus network.

[0017] The identification data query signal is a query signal that can be transmitted by the BUS control unit. The identification data query signal is a specific query signal that differs from other query signals of the BUS control unit. The BUS operating devices recognize the identification data query signal. Provision can be made for the respective identification data to be stored in a memory unit of the respective BUS operating device. As soon as a respective BUS operating device receives an identification data query signal via the network line, provision can be made for the identification data to be read from the respective memory unit of the respective BUS operating device and transmitted from the BUS operating device to the BUS control unit at the specified position in the transmission sequence.

[0018] For communication via the network cable, both the BUS control unit and the BUS operating devices have suitable transceiver units with which communication can be realized via the network cable. Furthermore, both the BUS control unit and the BUS operating devices can have respective power supply units, which enable power to be supplied from the BUS control unit to the BUS operating devices via the network cable.

[0019] According to a further development, it is proposed that the BUS control unit, after sending the query signal, compares the number of positions at which the BUS control unit receives the device data with a predetermined number of BUS operating devices in order to determine the function of the BUS network. The predetermined number of BUS operating devices can be determined, for example, during initialization of the BUS network. However, it can also be provided that the predetermined number of BUS operating devices is permanently set on the BUS control unit. A specification by the higher-level controller can also be provided. The predetermined number of BUS operating devices corresponds, for example, to the number of BUS operating devices connected to the network cable. If the function of the BUS network is undisturbed, the number of positions corresponds to the predetermined number of BUS operating devices.The specified number of BUS operating devices is the number of BUS operating devices that are in communication with the BUS control unit via the network cable. This allows the BUS control unit to determine that the available BUS operating devices have actually transmitted their device data to the BUS control unit. This improves the reliability of the intended operation of the BUS network.

[0020] Furthermore, it is proposed that if the number of positions is smaller than the specified number, the bus control unit transmits the identification data query signal. In this way, it is possible to determine which bus operating devices are operating as intended based on the number of positions at which identification data is received by the bus control unit in response to the identification data query signal. Furthermore, it is of course possible to determine whether the network line is faulty, for example, there is an interruption or the like. If the network line is interrupted, for example, subsequent bus operating devices can no longer communicate with the bus control unit. This can also be determined in this way.If the BUS control unit detects that the number of positions does not correspond to the specified number, it can send a message, for example, to the higher-level control system. It can also be configured for the BUS control unit to stop or reduce the intended operation of the BUS network.

[0021] It is further proposed that the transmission sequence be adjusted based on the individual identification data received by the bus control unit from the bus operating devices. This development particularly applies to the case where the number of positions is smaller than the specified number. This allows, for example, deactivated or faulty bus operating devices to be removed from the transmission sequence, so that the intended operation according to the daisy chain method can be maintained even in this case. The reliability of the intended operation of the bus network can thus be further improved.

[0022] Furthermore, it is proposed that the bus control unit assigns a position in the transmission sequence to the bus operating devices based on the individual identification data received from them. In particular, this can involve a reassignment or reconfiguration. The assignment of positions in the transmission sequence can be carried out according to a standardized initialization procedure for operation according to the daisy-chain method.

[0023] It is further proposed that the BUS control unit determines at least one error position, wherein the error position is a position in the transmission sequence at which the assigned BUS control unit is not receiving any device data. In this case, the BUS control unit can assume a malfunction or fault. For example, the BUS operating device to which this position is assigned can be deactivated or faulty and therefore not transmitting any device data. However, it is also possible that the network line is faulty, for example, due to an open circuit or a short circuit. In this case, the BUS control unit can, for example, repeat the transmission of the query signal. However, it can also be provided that the BUS control unit issues a fault message, for example to the higher-level controller.

[0024] Furthermore, it is proposed that the BUS control unit determines the identification data of the at least one associated BUS operating device depending on the stored identification data and the associated stored positions. This makes it possible to determine the BUS operating device that did not transmit any device data to the BUS control unit in response to the query signal. It is therefore possible for the BUS control unit to identify the BUS operating device based on the stored identification data associated with the position. The BUS control unit can issue a corresponding message with the corresponding identification data of the affected BUS operating device, in particular to the higher-level controller, in order to carry out, for example, repair, maintenance, replacement, or the like with regard to the BUS operating device that caused the faulty position.

[0025] It is further proposed that the bus control unit activate a fault diagnostic routine depending on the at least one fault position or the at least one bus operating device associated with the identification data. This makes it possible to automatically at least partially investigate the functional readiness or the malfunction of the bus operating device and, if necessary, also rectify it. In particular, it is also possible to identify the respective bus operating device whose operation is malfunctioning. The reliability of the intended operation of the bus network can thus be further improved.

[0026] Furthermore, it is proposed that the BUS control unit issue a fault message depending on the at least one fault position or the at least one BUS operating device associated with the identification data of the associated BUS operating device. This fault message can, for example, be issued as a signal to the higher-level controller. However, it can also be provided that the BUS control unit issues an acoustic, visual, or haptic signal to an operator of the BUS network, a user, or maintenance personnel.

[0027] According to a further development, it is proposed that the BUS control unit determines the operating status of the network line based on a comparison of the number of positions at which the BUS control unit receives the device data with the specified number of BUS operating devices. This development has the advantage that any fault or malfunction can be narrowed down. The detection of a fault in the network line can, for example, depend on the fact that, from a certain position in the transmission sequence, no more device data is sent back in response to a query signal. In this case, it can be assumed that a fault is unlikely if there are several BUS operating devices that follow one another in the transmission sequence. This can further improve the maintenance of the BUS network.

[0028] With regard to the BUS control unit, it is further proposed that the BUS control unit have a power supply unit for supplying at least one of the BUS control units with electrical energy via the network cable for its intended operation. This allows the BUS operating unit to be designed to be particularly compact and cost-effective. At the same time, reliability can be increased. The power supply unit can, for example, have an electrical energy storage device such as an accumulator or the like. Furthermore, the power supply unit can also have a power supply connection for coupling an electrical energy source. The power supply connection can, for example, be designed to couple a power supply network or an on-board electrical system of a motor vehicle.

[0029] It is further proposed that the BUS control unit be designed to determine a disruption to the intended operation of the BUS network and, depending on this, to reconfigure the transmission sequence. According to this development, it is therefore possible for the BUS control unit to react to disruptions in the intended operation of the BUS network and to attempt to maintain partial intended operation by reconfiguring or reconfiguring the transmission sequence. By reconfiguring the transmission sequence, the available BUS operating devices can be reinserted into the daisy chain process, so that the operation of the BUS network can be maintained with the available BUS operating devices. At the same time, it can be provided that the BUS control unit sends a corresponding message, for example, to the higher-level controller or the like.

[0030] The advantages and effects stated for the method according to the invention naturally also apply to the same extent to the BUS control unit according to the invention, where applicable, as well as to the computer program product according to the invention and the computer-readable data carrier, and vice versa. In particular, method features can therefore also be formulated as device features, and vice versa.

[0031] Further features of the invention emerge from the claims, the figures and the description of the figures. The features and combinations of features mentioned above in the description, as well as the features and combinations of features mentioned below in the description of the figures and / or shown alone in the figures can be used not only in the respective combination specified, but also in other combinations without departing from the scope of the invention. Thus, embodiments are to be regarded as encompassed and disclosed by the invention that are not explicitly shown and explained in the figures, but which emerge and can be produced by separate combinations of features from the explained embodiments. Embodiments and combinations of features are also to be regarded as disclosed that therefore do not have all the features of an originally formulated independent claim.Furthermore, embodiments and combinations of features, in particular those presented above, are to be considered disclosed that go beyond or deviate from the combinations of features presented in the claims. For applications or application situations that may arise with the method and that are not explicitly described here, it may be provided that, according to the method, an error message and / or a request for user feedback is output and / or a default setting and / or a predetermined initial state is set.

[0032] Showing:

[0033] Fig. 1 is a schematic diagram of a BUS network with a BUS control unit and several BUS operating devices that are coupled to each other by means of a network line of the BUS network, the BUS network being operated according to a daisy chain method,

[0034] Fig. 2 is a schematic signal representation for a signal sequence of device data of the BUS operating devices, which they send in response to a query signal,

[0035] Fig. 3 is a schematic signal representation like Fig. 2, in which one of the BUS operating devices is not sending any device data due to a fault,

[0036] Fig. 4 is a schematic signal representation like Fig. 2, in which the network line between two consecutively arranged BUS operating devices is interrupted, and

[0037] Fig. 5 is a schematic flow diagram for a process sequence for operating the BUS network.

[0038] Fig. 1 shows a schematic block diagram of a BUS network 1, which has a network line 9, to which a BUS control unit 2 and BUS operating devices 3 to 8 are connected, of which only the BUS operating devices 3 to 5 are shown in Fig. 1. The BUS operating devices 3 to 8 are connected serially to the BUS control unit 2 via the network line 9. The BUS control unit 2 and the BUS operating devices 3 to 8 are also included in the BUS network 1. With regard to the connection to the network line 9, the BUS operating devices 3 to 8 are essentially identical in this case. They are further designed such that the network line 9 is looped through the BUS operating devices 3 to 8. Each of the BUS operating devices 3 to 8 has its own power supply unit 11, an operating device control unit 13 as well as a controllable current source 12 and a line resistance Rs.The BUS operating devices 3 to 8 are essentially interconnected in series and connected to the BUS control unit 2. The BUS network 1 is operated according to a daisy-chain method.

[0039] Each of the BUS operating devices 3 to 8 comprises a respective sensor, which is included in the respective operating device control unit 13. The sensors are not shown in detail and do not need to be identical in this case. The sensors can, for example, detect temperature, humidity, light, and / or the like. It can also be provided that the sensors are a camera, in particular an infrared camera, a LIDAR, an ultrasonic sensor, and / or the like. In principle, however, the BUS operating device 3 to 8 can also have one or more actuators that can be controlled by means of control commands from the BUS control device 2.

[0040] The BUS control unit 2 has, in addition to a power supply unit 10, which not only supplies electrical energy for the intended operation of the BUS control unit 2, but also electrical energy for the operation of the BUS operating devices 3 to 8, so that the power supply unit 10 is able to supply the BUS network 1 essentially completely with electrical energy.

[0041] In addition, the bus control unit 2 has a control unit 41 configured to operate the bus network 1 according to the daisy chain method. The operating device control units 13 use their sensors to record sensor values ​​and make them available as device data.

[0042] Fig. 2 now shows, in a schematic signal representation, how the device data is retrieved from the BUS operating devices 3 to 8 via the network line 9. First, the BUS control unit 2 sends a query signal 22 via the network line 9 to the BUS operating devices 3 to 8 during undisturbed, normal operation. In an initial process sequence not further specified, the BUS control unit 2 previously assigned individual positions 23 to 28 to the BUS operating devices 3 to 8 in a transmission sequence 14. The BUS operating devices 3 to 8 receive the query signal 22 and send their respective device data at the previously assigned individual positions 23 to 28 in the predetermined transmission sequence 14 via the network line 9 to the BUS control device 2. In Fig. 2, the positions 23 to 28 are shown in the transmission sequence 14 in response to the query signal 22.Thus, the BUS operating device 3 sends its device data at position 23, the BUS operating device 4 sends its device data at position 24, the BUS operating device 5 sends its device data at position 25, the BUS operating device 6 sends its device data at position 26, the BUS operating device 7 sends its device data at position 27 and the BUS operating device 8 sends its data at position 28. Positions 23 to 28 follow one another immediately in time.

[0043] Fig. 3 shows a schematic signal diagram like Fig. 2, but in this illustrated signal sequence, the BUS operating device 5 is defective and is not transmitting any device data. This is indicated in FIG. 3 by the fact that position 25 contains an X. Position 25 is therefore omitted from the transmission sequence. This shifts the positions of the subsequent response signals. Therefore, due to its query signal 22, the corresponding device data only arrives at the BUS control unit 2 from five of the BUS operating devices 3 to 8, namely at positions 23, 24 and 26 to 28. This can lead to a signal processing error in the BUS control unit 2, which at least hinders, if not completely disrupts, the further operation of the BUS network 1.

[0044] Fig. 4 shows a schematic signal diagram, while Fig. 2 shows a further situation in which a fault exists between the BUS operating devices 5 and 6 with respect to the network line 9, in this case an interruption. As can be seen from Fig. 4, the BUS control unit 2 receives only the device data from the BUS operating devices 6 to 8 at positions 26 to 28 in response to the query signal 22. The device data from the BUS operating devices 3 to 5 at positions 23 to 25 cannot be transmitted to the BUS control unit 2 due to the interruption of the network lines 9. Here, too, this can lead to a significant disruption in the intended operation of the BUS network 1.

[0045] Fig. 5 shows a schematic flow diagram of how the problem explained with reference to Figs. 3 and 4 can be reduced or eliminated by means of suitable control of the BUS control unit 2. The method begins with step 15, in which the motor vehicle is started. In a subsequent step 16, the BUS control unit 2 initializes the BUS network 1, as explained, for example, in the DSI3 Bus Standard of February 16, 2011. In this context, an identification data query signal is sent to the BUS operating devices 3 to 8 for transmitting individual identification data stored in a readable manner in the BUS operating devices 3 to 8. The BUS operating devices 3 to 8 receive the identification data query signal from the BUS control unit 2. The BUS operating devices 3 to 8 send their respective individual identification data to the BUS control unit 2 according to the specified transmission sequence 14.The BUS control unit 2 receives the individual identification data and assigns them to the respective BUS operating device 3 to 8 depending on a respective position in the specified transmission sequence 14.

[0046] In a subsequent step 18, a check is performed to determine whether identification data is available for bus operating devices 3 to 8. At step 17, it is determined that no identification data is available for a specific one of bus operating devices 3 to 8, whereas at step 19, it is determined that identification data is available for a specific one of bus operating devices 3 to 8.

[0047] In step 20, a check is then carried out to determine whether the initialization, i.e., in particular the position assignment to the BUS operating devices 3 to 8, was successful. If the assignment was successful, the method continues with step 21, in which the stored identification data is compared with the identification data obtained during initialization. If the respective identification data are identical, the method continues with step 30 and ends, and the intended operation of the BUS network 1 is started or continued. If, however, there is a discrepancy between the stored identification data and the identification data obtained during initialization, the storage process is triggered in step 29, in which the respective received identification data is assigned to positions 23 to 28 and stored in the memory unit of the control unit 41, which in this case is embodied in the BUS control device 2.The process then continues with step 30.

[0048] If it is determined in step 20 that the initialization was unsuccessful, the process continues with step 31. In step 31, a check is performed to determine whether the stored identification data in the BUS control unit 2 is available and consistent. If this check is negative, the process continues with step 32.

[0049] In step 32, a check is made to determine whether initialization, in particular addressing, for all BUS operating devices 3 to 8 was successful. If this check is negative, the process continues with step 33. In step 33, a message is output that BUS network 1 has an addressing error. The process then continues with step 34. In step 34, a check is made to determine whether the error occurred due to a debouncing time. If the result of this check is negative, the process continues with step 16. If, however, the result of the check in step 34 is positive, a message is output in step 35, which BUS operating device 2 transmits to a higher-level controller (not shown).

[0050] If, however, the test result in step 32 is positive, the process continues with step 40. In step 40, the first faulty bus operating device 3 to 8 is identified and reported. From step 40, the process then continues with step 34, as previously explained.

[0051] If the check in step 31 is positive, the identification data of the storage unit assigned to the respective positions 23 to 28 are compared with the identification data received from the bus operating device 2 based on the identification data query signal. This occurs in step 36, and the method continues with step 37. In step 37, the bus operating devices 3 to 8 that are unavailable or faulty are then determined. The method then continues with step 40, as previously explained.

[0052] As can be seen from the preceding process flow, the BUS control unit 2 can be used to determine whether, and if so, which BUS operating devices are no longer participating in the intended operation of the BUS network 1. The BUS control unit 2 can then automatically reconfigure the BUS network 1. Positions 22 to 28 can be reassigned to the available BUS operating devices 3 to 8, whereby the number of positions is reduced due to the unavailable BUS operating devices 3 to 8. The BUS network 1 can therefore maintain its intended operation with the still available BUS operating devices.

[0053] The embodiments serve solely to explain the invention and are not intended to limit it.

Claims

Patent claims 1. Method for operating a BUS network (1), with a BUS control unit (2) and a plurality of BUS operating devices (3 to 8) which are coupled to one another by means of a network line (9) of the BUS network (1), wherein the BUS network (1) is operated according to a daisy chain method, in which the BUS control unit (2) sends a query signal (22) via the network line (9) to the BUS operating devices (3 to 8), the BUS operating devices (3 to 8) receive the query signal (22) and send respective device data of the BUS operating devices (3 to 8) at a predetermined position (23 to 28) in a predetermined transmission sequence (14) via the network line (9) to the BUS control unit (2), the BUS control unit (2) receives the device data and, depending on the position (23 to 28) in the transmission sequence (14) assigns the respective received device data to a respective one of the BUS operating devices (3 to 8), characterized in thatthat the BUS control unit (2) sends an identification data query signal for transmitting individual identification data stored in the BUS operating devices (3 to 8) in a readable manner to the BUS operating devices (3 to 8), the BUS operating devices (3 to 8) receive the identification data query signal, the BUS operating devices (3 to 8) send their respective individual identification data to the BUS control unit (2) in accordance with the predetermined transmission sequence (14), the BUS control unit (2) receives the individual identification data, assigns the respective identification data to the respective BUS operating device (3 to 8) depending on a position (23 to 28) in the predetermined transmission sequence (14), and stores the respective identification data with the respective position (23 to 28) assigned to the respective identification data.

2. Method according to claim 1, characterized in that the BUS control unit (2) after sending the query signal a number of positions at which the BUS control unit (2) receives device data, compares it with a predetermined number of BUS operating devices (3 to 8) in order to determine the function of the BUS network (1 ).

3. Method according to claim 2, characterized in that, if the number of positions is smaller than the predetermined number, the BUS control unit (2) transmits the identification data query signal.

4. Method according to claim 3, characterized in that the transmission sequence is adapted on the basis of the individual identification data received by the BUS control device (2) from the BUS operating devices (3 to 8).

5. Method according to claim 4, characterized in that the BUS control device (2) assigns a position in the transmitter sequence to the BUS operating devices (3 to 8) depending on the individual identification data received from the BUS operating devices (3 to 8).

6. Method according to one of the preceding claims 2 to 5, characterized in that the BUS control unit (2) determines at least one error position, wherein the error position is a position in the transmission sequence at which the associated BUS control unit (2) does not receive any device data.

7. Method according to claim 6, characterized in that the BUS control device (2) determines the identification data of the at least one associated BUS operating device (3 to 8) depending on the stored identification data and the associated stored positions.

8. Method according to claim 6 or 7, characterized in that the BUS control device (2) activates a fault diagnosis routine depending on the at least one fault position or the at least one BUS operating device (3 to 8) associated with the identification data.

9. Method according to one of the preceding claims 6 to 8, characterized in that the BUS control device (2) issues a fault message depending on the at least one fault position or the at least one BUS operating device (3 to 8) associated with the identification data.

10. Method according to one of the preceding claims 2 to 9, characterized in that the BUS control device (2) determines an operating state of the network line (9) depending on the comparison of the number of positions at which the BUS control device (2) receives the device data with the predetermined number of BUS operating devices (3 to 8).

11. Computer program product with program code means, which are stored in particular in a computer-readable medium, in order to at least partially carry out the method for operating a BUS network (1) according to one of the preceding claims when the computer program product is processed on a computer unit of a BUS control device (2) of the BUS network (1).

12. Computer-readable data carrier with program code instructions which, when executed by a computer unit, cause the computer unit to at least partially carry out the method for operating a BUS network (1) according to one of the preceding claims 1 to 10.

13. BUS control device (2) for a BUS network (1), wherein the BUS network (1) comprises, in addition to the BUS control device (2), a plurality of BUS operating devices (3 to 8) which are coupled to one another by means of a network line (9) of the BUS network (1), wherein the BUS network (1) is operated according to a daisy chain method, wherein the BUS control device (2) is designed to send a query signal via the network line to the BUS operating devices (3 to 8), to receive respective device data of the BUS operating devices (3 to 8), which the BUS operating devices (3 to 8) send successively to the BUS control device (2) via the network line (9) in response to the query signal at a predetermined position in a predetermined transmission sequence, and depending on the position in the transmission sequence, to send the respective received device data to a to assign the respective ones of the BUS operating devices (3 to 8), characterized in that the BUS control device (2) is further designed to send out an identification data query signal for transmitting individual identification data stored in a readable manner in the BUS operating devices (3 to 8) to the BUS operating devices (3 to 8), to receive, in response to the identification data query signal, the respective individual identification data sent from the BUS operating devices (3 to 8) to the BUS control device (2) in accordance with the predetermined transmission sequence, to assign the respective identification data to the respective BUS operating device (3 to 8) depending on a position in the predetermined transmission sequence, and to store the respective identification data with the respective position which is assigned to the respective identification data.

14. BUS control device according to claim 13, characterized by a power supply unit (10) for supplying at least one of the BUS operating devices (3 to 8) with electrical energy via the network line (9) for the intended operation.

15. BUS control device according to claim 13 or 14, characterized in that the BUS control device (2) is designed to determine a disturbance of the intended operation of the BUS network (1) and to reconfigure the transmission sequence depending thereon.

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