Motor vehicle with multiple control units that provide different vehicle functions in the motor vehicle, as well as methods for configuring the control units and control unit

Description

[0001] The invention relates to a motor vehicle having a plurality of control units configured to provide a respective vehicle function in the motor vehicle, wherein the vehicle functions of the control units differ. The control units are connected by a common bus line, for example, to enable them to be controlled so that they execute their vehicle function. The invention also includes a corresponding control unit for a motor vehicle and a method for configuring control units in a motor vehicle so that the control units set up or provide a respective vehicle function so that it can be executed.

[0002] Currently, vehicles have control units that are uniquely identified. For example, a device-specific, consecutive serial number or part number is saved during production. This can lead to an error later during installation if two control units are swapped, meaning the control units are not in the intended installation position. If, for example, such an incorrectly installed control unit is controlled via a bus line using its part number, the control unit will still perform the vehicle function it provides, but will be in the wrong installation position. One example of such control units are those for display modules, several of which can be connected to a vehicle computer via a bus line so that the computer can output display values ​​to a vehicle occupant.

[0003] From DE 10 2008 004 125 B4, it is known that several control circuits can be connected to one another via a ribbon cable of a data bus, with data bits being applied simultaneously to all control circuits via parallel data lines of the ribbon cable. To assign bus addresses for the control circuits, two additional lines are provided, each of which has alternating line breaks between two of the control units, so that only one of the two lines is electrically conductive between these control units at a time. A signal to trigger a readdressing is sent sequentially via these two lines, while the address to be used is specified via the parallel data lines.Once a control circuit has received an address assignment signal and stored the corresponding bus address, it forwards the address assignment signal to the next control circuit, which then receives the next bus address via the data lines. Specifying the bus address requires a controller that transmits the respective bus address via the data lines.

[0004] DE 10 2005 056 294 B4 discloses a method for assigning bus addresses to bus devices. Each bus device is assigned a bus address in turn. The currently assigned bus address is communicated to all bus devices via a broadcast telegram. However, outside the bus line, only one bus device is sent a further signal that only this device can detect, so that only this bus device stores the currently assigned bus address. Thus, an additional communication path is always required in addition to the bus line.

[0005] EP 1 573 974 B1 discloses a self-assignment of bus addresses, in which bus participants are interconnected in the bus system via a daisy chain connection. This daisy chain connection only occurs during address assignment, for which the bus participants require additional switching means to split the bus line into bus branches. For the address assignment itself, each control unit checks whether an electrical parameter on the outgoing bus branch indicates that another control unit is connected downstream. If this is not the case, such a control unit assigns itself an address and changes its circuit state, which changes the electrical parameter for the next control unit, so that the control unit there also assigns itself an address. This address assignment is based on precise measurement of electrical parameters and time values, which requires correspondingly complex and precise circuits.

[0006] Furthermore, document WO 2010 / 147 516 A1 discloses a method for activating at least one function stored in a vehicle communication system in a heavy vehicle or work machine, document WO 2010 / 074 677 A1 discloses a method and apparatus for performing automatic device configuration, and document WO 2017 / 024 226 A1 discloses a method and apparatus for enabling the recognition and assignment of unique addresses for identical or similar devices that are connected together in a serial chain of devices in a high-speed communication link.

[0007] The invention is based on the object of installing control units with specific, different vehicle functions in a motor vehicle at the correct installation location where the respective vehicle function is required or intended.

[0008] The object of the invention is achieved by the subject matter of the independent patent claims. Advantageous developments of the invention result from the features of the dependent patent claims and are described in the following description and the figures.

[0009] The invention provides a motor vehicle with multiple control circuits or control units. The control units are configured to provide a respective vehicle function in the motor vehicle, wherein the vehicle functions of the control units are different, and wherein the control units are connected by a common bus line, which is routed or laid sequentially through a respective communication circuit of the control units, thus interconnecting the control units in a daisy-chain configuration. The control units thus share a common bus line, although, as will be described below, it is not necessary to provide a continuous bus line that also galvanically connects all control units.The bus line is routed or laid within the control units through their respective communication circuits, so that data, bus messages, or bus telegrams are transmitted along the bus line through the communication circuits located along the transmission path. Another term for daisy-chain connection is series connection or chain connection.

[0010] In order to prevent the control units with their different vehicle functions from being installed in the motor vehicle at swapped installation positions, the invention provides that each of the vehicle functions is implemented in each of the control units and a processor circuit is configured to determine a position indication which indicates a position of the respective control unit within the daisy chain connection (i.e. which control unit it is in the daisy chain connection in each case), and depending on the determined position indication, to select a vehicle function assigned to the position from the implemented vehicle functions and to offer the selected vehicle function, in particular only the selected vehicle function or only the multiple vehicle functions assigned to the position, in the motor vehicle for activation."Implementing" a vehicle function here means that program code or software for each of the vehicle functions is stored, stored, or provided in the processor circuit of the respective control unit. Each of the vehicle functions can therefore potentially be provided by each of the control units at each of the installation functions. If the vehicle function is hardware-based or provided by a hardware, circuit, or component, each of the control units is equipped with the corresponding hardware and / or component. The control units are thus generic, meaning they can be installed in any installation position and can provide or execute the vehicle function intended for that installation position.This means that each control unit only needs to find out in which installation position it has been installed in order to select the correct vehicle function, i.e. at least one function intended for this installation position. For this purpose, each of the control units can, for example, execute a detection routine using its processor circuit, so that the control unit can automatically detect in which position along the daisy chain connection the control unit is located. An installation position in the vehicle therefore corresponds to a respective position in the daisy chain connection. Accordingly, by laying or wiring the installation positions to the bus line, it can be ensured or provided that when the control units are installed in the installation position and connected to the bus line, the position of the control unit within the daisy chain connection provides a signal or indication of the corresponding installation position in the vehicle.If the processor circuit in a control unit detects a specific position of the respective control unit within the daisy chain connection, this position is assigned a corresponding installation position in the motor vehicle and the processor circuit can select at least one vehicle function in the control unit assigned to the position in the daisy chain connection and thus the installation position and operate the selected vehicle function or make it available or offer it for activation. In particular, only this vehicle function is offered for activation and the other implemented vehicle functions remain deactivated or inactive. Offering means that the respective vehicle function can be called up or triggered in the control unit, for example by external control, for example via the bus line or by operation by a user.Each of the control units therefore represents a component in the motor vehicle in which all the necessary information is provided or stored to be able to assume each role within the daisy chain connection, in that a generic set of different vehicle functions is provided in the control unit and only the vehicle function intended for the installation position in the motor vehicle is enabled or provided for selection or activation.

[0011] The invention provides the advantage that the control units can be installed in any of the installation positions provided for the control units in the motor vehicle without prior sorting or selection. Each control unit then selects the vehicle function that belongs to or matches the installation position based on its position in the daisy chain. This prevents a control unit from being mixed up during installation of the control unit in the motor vehicle, as each control unit can be installed in any of the possible installation positions for the control units.

[0012] The invention also includes further developments that result in non-trivial additional technical advantages.

[0013] A further development involves interrupting the bus line in each control unit through its communication circuit, thus splitting it into bus branches, so that two bus lines terminate at each communication circuit, or at each communication circuit except for the last communication circuit in the daisy chain. Each two control units are thus connected via a separate bus branch of the bus line.Each of the control units or each of the control units except for the last one in the daisy chain is set up to receive a request message with a position indication along the daisy chain in sequence by means of its communication circuit via one of its bus branches (incoming bus branch), to determine its own position indication depending on the received position indication and to send a request message with the own position indication just determined to the next control unit in the daisy chain by means of its communication circuit via the other of its bus branches (outgoing bus branch).The bus line is thus split into individual bus branches by the communication circuits, so that a bus message or bus telegram is only transmitted along the bus line past one control unit to the next if the control unit itself actively reads the bus message or bus telegram from the incoming bus branch using its communication circuit and transmits or sends it back to the outgoing bus branch to the next control unit. The bus line can be designed for unidirectional or bidirectional communication. The bus line can be single-core or multi-core. It can be designed as a flat cable, twisted-pair cable, coaxial cable, or optical cable, to name just a few examples.

[0014] An exemplary detection routine for determining its own position information can, for example, provide in the respective control unit that its own position information is determined by incrementing a counter or counter value, so that the first control unit assigns itself, for example, the serial number 1 and communicates this serial number to the next control unit, which then assigns itself serial number 2 as the position information by incrementing and signals this to the next control unit. However, the detection routine can additionally or alternatively determine its own position information based on the received position information using an assignment rule, for example a table, which, for example, provides information about the installation position (e.g., "instrument cluster" or "head-up display" or "center console").By first assigning its own position information to itself using its detection routine and then using this own position information to trigger or initiate the determination of its own position information in the next control unit, the predecessor in the daisy chain connection (i.e., the preceding control unit) determines the function or vehicle function in the subsequent control unit. This assignment or determination of the position takes place in an initialization mode, which can be triggered by a vehicle computer sending the first request message to the first control unit in the daisy chain connection, i.e., a control unit at one end of the daisy chain connection. This request message can contain, for example, position 0 or -1 as a position information, whereupon the first control unit determines its own position information.Thus, through the series connection or daisy chain connection, after the installation or mounting of the control units, a position in the daisy chain connection or chain can be determined independently by each control unit using this predecessor-successor principle.

[0015] A further development comprises that each of the control units is configured to determine a device-specific bus address for bus communication as a position indication or to form the bus address from the determined position indication (e.g., using a mapping table). In order to also use the position indication for bus communication, a device-specific bus address for bus communication can be determined as a position indication, or the bus address can be derived or formed from the determined position indication (e.g., "third control unit in the interconnection"), which can be done, for example, using a mapping table or an assignment rule. This also results in a unique bus address for each installation position, so that by addressing a bus message or bus telegram to this bus address, the corresponding control unit in this installation position, which belongs to this bus address, is addressed or controlled.

[0016] The vehicle function provided by the respective control unit depending on the position in the daisy chain connection and / or the installation position can, for example, be an output graphic or lighting intended for the respective installation position. Depending on the installation position, a different output graphic or lighting results, to name just a few examples. In addition or alternatively, the vehicle function can also provide that the control unit uses a device-specific bus address for bus communication via the bus line, i.e. is addressed on the bus line via a specific bus address used only for this control unit. In other words, only the respective control unit reacts to the bus address by executing or processing the respective bus message or bus telegram addressed to this bus address.The control unit is then configured, as a vehicle function or as a component of the vehicle function, to accept bus messages at this bus address (to process their message content or execute a control command contained in the bus message) and / or to send bus messages with this bus address as the sender. However, each control unit can communicate in the manner described using any possible bus address, since all vehicle functions and thus all bus addresses are implemented. However, the respective control unit is limited to the bus address that corresponds to its position in the daisy chain connection. Accordingly, a further development comprises the vehicle function using the device-specific bus address for bus communication via the bus line.

[0017] A further development involves some or all of the control units being identical in design and / or having the same part numbers and / or model numbers. This makes it possible to manufacture the control units using a similar or consistent manufacturing process. During the manufacturing process, it is not necessary to pay attention to the final installation position in the vehicle where each control unit is installed. Each control unit configures itself in the manner described by determining the position information after it has been installed.

[0018] A further development comprises some or all of the control units being interconnected with a display module and being configured to control the respective display module using the selected vehicle function. This allows a graphic output to be provided in the motor vehicle via multiple display modules of identical construction, so that no special measures are required when installing the display modules to prevent confusion of the display modules when installing them in their respective positions. A display module can be based, for example, on micro-LEDs and / or OLEDs (organic light-emitting diodes) or TFTs. The display modules are addressable via the bus line, so that the display content of the display modules can be defined or controlled via the control units.

[0019] A further development comprises that several of the display modules in a display device are combined to form a multi-part display having a total display area, and the position of the control unit of the respective display module within the daisy-chain connection corresponds to a position of the associated display module in the total display area. In other words, a display device or a display can be provided that has a total display area that is larger than the individual display area of ​​each of the display modules. Each of the display modules represents a respective display panel of the total display area. For example, it can be provided that the display modules are arranged flush next to one another, so that the total display area results as a closed area.Where the respective display area of ​​each display module is arranged within the total display area (for example, at the edge or in the center) is coded based on the position of the control unit in the daisy-chain circuit, with a corresponding assignment provided by the arrangement of the bus line in the vehicle. This means that an overall display area can be provided in the vehicle with inexpensive, smaller display modules, without the need for a costly, correspondingly large individual display module that provides the entire display area. Nevertheless, during assembly or provision of the overall display area, no interchange of the control units can cause a faulty display or incorrect display content due to interchanged control units.

[0020] A further development comprises each of the control units having an ASIL, and starting from the first control unit in the daisy-chain connection, the control units are arranged in descending order according to their ASIL. The ASIL describes a protection of the respective control unit against failure or a failure of its functionality. By connecting the control units in descending order according to their ASIL, if a control unit fails and this interrupts bus communication in the bus line to downstream control units, only the control unit with the same or a lower ASIL is affected. Control units with the same ASIL must, of course, be connected directly one after the other according to the order. This ensures that the first control unit can continue to be addressed or operated via the bus line, even if all other control units or a downstream control unit fails.

[0021] Additionally or alternatively, it can be provided that at least one bridging switch is provided in the respective communication circuit, which bridges the electrical separation between the connected bus branches when a defect or malfunction or failure of the control unit is detected, so that the incoming bus branch and the outgoing bus branch are electrically bridged or electrically connected in the communication circuit, i.e. even when the communication circuit is inactive or switched off, data can be transmitted through the communication circuit in the bus line because the bus branches are electrically connected to one another. A transistor switch, for example, can be provided as the respective bridging switch. The respective bridging switch can be implemented, for example, by the processor circuit of the control unit and / or by a monitoring unit of the communication circuit itself.A monitoring unit can, for example, have an integrated circuit that can, for example, provide a so-called watchdog functionality for the control unit.

[0022] In the context of the term "first control unit," this refers to the control unit that is connected to a vehicle computer or vehicle computer via the bus line directly, or without the interposition of another control unit. The last control unit in the daisy-chain connection is located at the other end. Thus, each of the control units can be controlled differently in the vehicle computer according to its position in the daisy-chain connection or its installation position in the vehicle, by utilizing the corresponding vehicle function. Particularly if the use of a unique bus address in each control unit is also provided as a vehicle function, the vehicle computer can determine which control unit at which installation position is controlled by the vehicle computer via the bus line by selecting a corresponding bus address.

[0023] A further development accordingly comprises that the control unit of one end of the daisy-chain connection (namely the said first control unit) is connected via the bus line to a vehicle computer of the motor vehicle, which is configured to control the control units via the bus line depending on their position in the daisy-chain connection and / or their installation position and / or depending on their vehicle function.

[0024] A further development comprises the bus line additionally being routed back from the control unit at the other end of the daisy-chain connection to the vehicle computer, and the vehicle computer having a control routine configured to send a first message via the bus line to the control unit at one end of the daisy-chain connection and to check whether a second message triggered by this message can be received from the control unit at the other end, and to signal an interrupted bus line if the second message is not received. In other words, the bus line forms a ring line that originates from the vehicle computer, is routed successively through the communication circuits of the control units, and returns to the vehicle computer.If a first message is then sent to the first control unit and the control unit forwards this message or triggers the subsequent or downstream control unit to also generate a message, then in a domino effect the last control unit in the daisy chain connection will also generate a message, referred to here as the second message, which is then transmitted back to the vehicle computer via the returned bus line. If the second message is received, the vehicle computer confirms that the bus line is complete or undamaged and that all control units are ready to receive. If the second message is not received after a predetermined maximum waiting time, then the bus line is interrupted, for example because it is damaged, and / or one of the control units has failed and thus the daisy chain connection is interrupted by its communication circuit.The first message can, for example, be the described request message for determining the control units' own position. If the last control unit in the daisy-chain connection then also sends such a request message in the returned bus line, i.e. in the last bus branch, to the vehicle computer, the vehicle computer knows that the last control unit has also determined its position. This second message can even be used to determine how many control units are connected in total in the bus line. The first message can therefore trigger a count of the control units, and the vehicle computer can determine whether the determined number of control units corresponds to a specified target number. If the determined number is not equal to the target number, an error signal can be generated.

[0025] The invention also provides a control device for a motor vehicle according to claim 11.

[0026] The control unit has a processor circuit and a communication circuit for connection to a bus line, and a plurality of predetermined vehicle functions are implemented in the processor circuit of the control unit, wherein the control unit is configured such that a plurality of control units are arranged in the motor vehicle, the vehicle functions of the control units are different, and the plurality of control units are connected by the bus line, which are successively routed through a respective communication circuit of the control units, thereby interconnecting the control units in a daisy-chain configuration, wherein each of the vehicle functions is implemented in the control unit, wherein the processor circuit is configured to determine a position indication which indicates a position of the control unit within the daisy-chain configuration formed by the bus line,and, depending on the determined position information, selecting a vehicle function assigned to the position from the implemented vehicle functions and offering the selected vehicle function for activation in the motor vehicle. Several control units of this embodiment can thus be installed in a motor vehicle without the risk of confusion.

[0027] The invention naturally also provides for further developments of the control devices, as already described in connection with the further developments of the motor vehicle according to the invention.

[0028] The invention also provides a method for configuring control units in a motor vehicle according to claim 12 so that a vehicle function is provided by the control units, wherein the vehicle functions of the control units are different and the control units are connected by a common bus line which is routed successively through the control units and thereby connects the control units in series to form a daisy chain connection.

[0029] To avoid confusion during installation of the control units, it is provided that each of the vehicle functions is implemented in each of the control units, and a processor circuit in each of the control units determines a positional information that indicates a position of the respective control unit within the daisy-chain connection. Depending on the determined positional information, the processor selects a vehicle function assigned to the position from the implemented vehicle functions and makes the selected vehicle function available for activation in the motor vehicle. The method according to the invention thus results during operation of the motor vehicle according to the invention when the control units independently determine their position in the daisy-chain connection.

[0030] The invention also includes further developments of the method which are characterized by features such as those already described in connection with the further developments of the motor vehicle according to the invention.

[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 specified combination, but also in other combinations or on their own.

[0032] The invention will now be explained in more detail using a preferred embodiment and with reference to the drawings. The sole figure shows: Fig. a schematic representation of an embodiment of the motor vehicle according to the invention, which can carry out an embodiment of the method according to the invention.

[0033] The figure shows a motor vehicle 10, which in a conventional manner may have a vehicle computer 11. The motor vehicle 10 may be configured, for example, as a road vehicle, such as a passenger car. However, this is only to be understood as an exemplary embodiment. The vehicle computer 11 may have a processor circuit 12, which may comprise, for example, one or more microprocessors. The vehicle computer 11 can control several control units 13, which for this purpose may be connected one after the other in a series circuit or daisy-chain circuit 14 via a bus line 15. The bus line 15 may be single-core or multi-core, as already described.Each of the control units 13 can be connected to the bus line 15 by means of a communication circuit 16, which can be designed such that data, messages, or telegrams sent from the vehicle computer 11 via the bus line 15 are received in the communication circuit 16 of the first control unit 13 (here additionally provided with the reference numeral 17), and the bus line 15 is interrupted or separated such that the data does not reach the next control unit 13 (here additionally provided with the reference numeral 18), but only in the event that the communication circuit 16 itself transmits the data to the next control unit 18, which in turn can receive the data. In other words, the bus line 15 is divided into bus branches 19 by the communication circuits. The communication circuits 16 can be designed, in a manner known per se, as so-called bus controllers or bus connections.

[0034] This control unit 13 can additionally have a processor circuit 20, by means of which a vehicle function 21 can be provided in the control unit 13, which differ from one another, which is illustrated in the figure by the use of the different designations F1, F2, F3, F4. Each control unit 13 can also provide more than one vehicle function 21, i.e., each provide a range of functions consisting of several vehicle functions, whereby the ranges of functions of the control units 13 differ from one another. Examples of vehicle functions 21 can be: the use of a device-specific bus address for the data bus D with the bus line 15; a control function for a respective display module 22, which can be connected to the control unit and generates different graphics or display contents 23; and control functions for different circuits connected to the control unit.

[0035] The figure shows, by way of example, how a total mileage 24, a room temperature 25, a driving speed 26, and a speedometer 27, to name just a few examples, are displayed as a function F1 on the various display modules 22, which are shown here as examples. The vehicle computer 11 only needs to send the current value, and the control unit 13 can then generate the corresponding display content 23, i.e., the corresponding pixel values. The figure shows a further exemplary embodiment in which three of the control units 13 are arranged in a common display device or a common display 28. For example, a common total display area 29 can be provided by the three display modules 22, which are controlled by the control units 13 of the display 28, so that each display module 22 functions as a panel for providing a portion of the total display area 29.For this purpose, the display modules 22 can be arranged flush and adjacent to each other in pairs. For example, the display 28 can be a so-called head-up display for the motor vehicle 10.

[0036] The display module 22 for the speedometer 27 can, for example, be arranged in a combination instrument of the motor vehicle.

[0037] Although each of the control units 13 provides a different vehicle function 21, the control units 13 are preferably identical in construction and / or do not need to be differentiated from one another when it comes to the manufacture or assembly of the motor vehicle 10. Rather, each of the control units 13 can be used for any installation position of the control units 13. For this purpose, all required vehicle functions 21 are implemented in each of the control units 13, for example as corresponding software. So that each control unit 13 activates or provides the functions 21 required for the specific installation position in which the control unit 13 is located after assembly, the processor circuit 20 of the respective control unit 13 identifies the position within the daisy chain circuit 14 at which the control unit 13 is located.For this purpose, a request message 31 can be sent from the vehicle computer 11, which can be operated, for example, as a bus master, via the data bus D, i.e., the bus line 15, which is intercepted or read in the manner described in the communication circuit 16 of the first control unit 17. The request message 31 can, for example, specify an initial bus address A0 as the sender. By means of the communication circuit 16, the processor circuit 20 of the first control unit 17 can read the request message 31 and then generate a unique bus address A1, for example, as part of the vehicle function 21, by incrementing the received bus address A0. The incrementation can occur according to a predetermined rule, which is symbolically represented in the figure as A0+1. This is an example of a detection routine.The first control unit 17 thus has a unique bus address A1 and can recognize from the value of the bus address (A1) that it is the first control unit 17 in the daisy-chain connection 14. The first control unit 17 can then, in turn, send a request message 32 to the next control unit 18 in the daisy-chain connection 14, using its own bus address A1 as the sender. In the control unit 18, the request message 32 can be read out in the same way by the processor circuit 20 and, for example, as a component of the vehicle function 21, the control unit 18 can generate its own, control-unit-specific bus address A2 using its detection routine by incrementing the received bus address A1 (symbolically represented as A2=A1+1). This can be continued along the daisy-chain connection 14 using further request messages 32.The last control unit 33 in the daisy-chain connection 14 can, in turn, generate a request message 32 which, in the case of a return bus branch 19 to the vehicle computer 11, signals to the vehicle computer 11 that all control units 13 have been reached via the bus line 15 and that the bus line 15 is functional. The respective individual bus address represents a position indication 34 that correlates with or corresponds to a position of the respective control unit 13 within the daisy-chain connection 14. In addition to or as an alternative to determining a unique control unit-specific bus address as a position indication 34, the respective processor circuit 20 of each control unit 13 can also select and activate the vehicle function 21 from the totality of the implemented vehicle functions 21 (i.e., all vehicle functions F1, F2, F3, F4) depending on this position indication 34.Thus, for example, the display modules 22 can be identical in design, and each control unit 13, which controls one of the display modules 22, can determine the respective individual configuration of the display content 23, as described, depending on the position information 34. Furthermore, the display modules 22 can interact within the display 28, and the vehicle computer 11 can determine, using the position information 34 or the bus address, which part of an overall display content 36 should be displayed on which display module 22.Thus, by laying the bus line 15 along the possible installation positions for control units 13, the prior knowledge or information can be determined as to where this installation position is located in relation to the position within the daisy chain connection, which can be stored as an assignment table or as an assignment rule in the vehicle computer 11, i.e. a position assignment 37 can be provided in the processor circuit 12 of the vehicle computer 11, which corresponds to an assignment between installation position and position within the daisy chain connection, i.e. ordinal number (first control unit, second control unit and so on).

[0038] The described "daisy chaining" (daisy chain connection 14) thus means that control units 13 are linked and connected to one another via the bus line 15. The goal is that, for example, consecutive display modules 22 of a display 28 can have the same part number. Therefore, they must identify themselves independently after installation in order to display the corresponding display contents 23 (e.g., total mileage 24, room temperature 25, driving speed 26).

[0039] The problem that is overcome is that several identical devices must be installed logically one after the other, especially more than two, but must then be able to be addressed individually. If, for example, the imaging unit (e.g. a head unit, i.e. the vehicle computer 11) is to show a display content 23 on display 2 (central display module 22), it must be ensured that the display data also reaches display 2, even though display 2 can have the same part number as every other display module 22 (i.e. displays 1, 3 and 4 in the example). The part number identity of the display modules 22 connected in series with their control units 13 is the most interesting case of series connection, but the idea also works with components that do not have the same part number.

[0040] Through the series connection or daisy chain connection 14, after installation, a position in the chain of daisy chain connections 14 can be independently determined by each control unit 13 using the predecessor-successor principle explained above. Each component has the necessary information to assume any role or vehicle function within the chain of daisy chain connections 14 (like a stem cell or generic circuit). The predecessor determines the function of the successor in the daisy chain connection 14. Since the components or control units 13 are also relevant in descending order along the chain (seen from the HU or the vehicle computer 11), i.e., they are ordered according to their ASIL, a failure of one of the components and the associated failure of the subsequent components can be handled logically and responded to accordingly. List of reference symbols

[0041] 10Motor vehicle 11Vehicle computer 12Processor circuit 13Control unit 14Daisy chain connection 15Bus line 16Communication circuit 17Control unit 18Control unit 19Bus branches 20Processor circuit 21Vehicle function 22Display module 23Display content 23Display modules 24Total mileage 25Room temperature 26Driving speed 27Speedometer 28Display 29Total display area 32Prompt message 33Control unit 34Position information 36Display content 37Position assignment DData bus

Claims

1. Motor vehicle (10) having a plurality of control units (13) configured to provide a respective vehicle function (21) in the motor vehicle (10), wherein the vehicle functions (21) of the control units (13) are different, and wherein the control units (13) are connected by a common bus line (15) which is guided successively through a respective communication circuit (16) of the control units (13) and thereby interconnects the control units (13) in series to form a daisy-chain interconnection (14), characterized in that in each of the control units (13) a) each of the vehicle functions (21) is implemented, and b) a processor circuit (20) is configured to determine a position indication (34) indicating a position of the respective control unit (13) within the daisy-chain interconnection (14), and, depending on the position indication (34) determined, to select a vehicle function (21) assigned to the position from the implemented vehicle functions (21) and to offer the selected vehicle function (21) for activation in the motor vehicle (10).

2. Motor vehicle (10) according to Claim 1, wherein the bus line (15) in each control unit (13) is interrupted by its communication circuit (16) and is thus separated into bus branches (19), with the result that two bus lines (15) end at each communication circuit (16) or at each communication circuit (16) apart from the last one in the daisy-chain interconnection (14), and each of the control units (13) or each apart from the last of the control units (13) in the daisy-chain interconnection (14) is configured to receive in turn a request message (32) with a position indication (34) in each case by means of the respective communication circuit (16) via one of its bus branches (19), to determine its own position indication (34) on the basis of the received position indication (34), and to send a request message (32) with its own determined position indication (34) to the next control unit (13) in the daisy-chain interconnection (14) by means of its own communication circuit (16) via the other of its bus branches (19).

3. Motor vehicle (10) according to one of the preceding claims, wherein each of the control units (13) is configured to determine, as a position indication (34), a device-specific bus address for bus communication or to form the bus address from the determined position indication (34).

4. Motor vehicle (10) according to Claim 3, wherein the vehicle function (21) comprises using the device-specific bus address for bus communication via the bus line (15).

5. Motor vehicle (10) according to one of the preceding claims, wherein some or all of the control units (13) are structurally identical and / or have the same item numbers and / or model numbers.

6. Motor vehicle (10) according to one of the preceding claims, wherein some or all of the control units (13) are each interconnected to a display module (22) and are configured to control the respective display module (22) by means of the selected vehicle function (21).

7. Motor vehicle (10) according to Claim 6, wherein a plurality of the display modules (22) are assembled in a display device to form a multi-part display having a total display area (29), and the position of the control unit (13) of the respective display module (22) within the daisy-chain interconnection (14) corresponds to a position of the associated display module (22) in the total display area (29).

8. Motor vehicle (10) according to one of the preceding claims, wherein each of the control units (13) has an ASIL and, starting from the first control unit (13) in the daisy-chain interconnection (14), the control units (13) are arranged in descending order according to their ASIL.

9. Motor vehicle (10) according to one of the preceding claims, wherein the control unit (13) of one end of the daisy-chain interconnection (14) is connected, via the bus line (15), to a vehicle computer (11) of the motor vehicle (10), which is configured to control the control units (13) on the basis of their position and / or on the basis of their vehicle function (21) via the bus line (15).

10. Motor vehicle (10) according to Claim 9, wherein the bus line (15) is additionally guided back to the vehicle computer starting from the control unit (13) of the other end of the daisy-chain interconnection (14), and the vehicle computer (11) has a control routine which is configured to send a first message to the control unit (13) of the one end of the daisy-chain interconnection (14) via the bus line (15) and to check whether a second message triggered by this message can be received from the control unit (13) of the other end, and to signal an interrupted bus line (15) if the second message is not received.

11. Control unit (13) for a motor vehicle (10), wherein the control unit (13) has a processor circuit (20) and a communication circuit (16) for connection to a bus line (15) and a plurality of predetermined vehicle functions (21) are implemented in the processor circuit (20) of the control unit (13), wherein the control unit is configured such that a plurality of control units (13) are arranged in the motor vehicle (10), the vehicle functions (21) of the control units (13) are different and the plurality of control units (13) are connected by the bus line (15) which is guided successively through a respective communication circuit (16) of the control units and thus the control units (13) are interconnected in series to form a daisy-chain interconnection (14), characterized in that each of the vehicle functions (21) is implemented in the control unit (13), and the processor circuit (20) is configured to determine a position indication (34) indicating a position of the control unit (13) within the daisy-chain interconnection (14) formed by the bus line (15), and, depending on the position indication (34) determined, to select a vehicle function (21) assigned to the position from the implemented vehicle functions (21) and to offer the selected vehicle function (21) for activation in the motor vehicle (10).

12. Method for configuring control units (13) in a motor vehicle (10) so that the control units (13) provide a respective vehicle function (21), wherein the vehicle functions (21) of the control units (13) are different and the control units (13) are connected by a common bus line (15) which is guided successively through the control units (13) and thereby interconnects the control units (13) in series to form a daisy-chain interconnection (14), characterized in that each of the vehicle functions (21) is implemented in each of the control units (13), and a processor circuit (20) in each of the control units (13) determines a position indication (34) indicating a position of the respective control unit (13) within the daisy-chain interconnection (14), and, depending on the position indication (34) determined, selects a vehicle function (21) assigned to the position from the implemented vehicle functions (21) and provides the selected vehicle function (21) for activation in the motor vehicle (10).