LIN bus via trunk bus tunnel

Abstract

An example relates to a system (10) for data transmission in a motor vehicle. The system (10) comprises: a central controller (11), in which at least one LIN master (11a) is configured; and at least one local controller (12), which is coupled to the central controller (11) by means of a first data connection (13). The local controller (12) is also coupled to a LIN bus (14) assigned to the LIN master (11a), to which at least one LIN slave (15a) is connected. In this case, the data transmission speed of the first data connection (13) between the central controller (11) and the local controller (12) is higher than the data transmission speed of the LIN bus (14). Other examples relate to a method (30) for controlling a LIN slave (15a) connected to the LIN bus (14) and a motor vehicle.

Description

Technical Field

[0001] Embodiments relate to a system for data transmission in a motor vehicle. The system comprises a central controller and at least one local controller. The system is configured to control a device via a LIN bus. Other embodiments relate to a method for controlling a LIN slave connected to a LIN bus and a motor vehicle having a corresponding system or configured to implement the disclosed method. Background Art

[0002] In motor vehicles, various devices of the motor vehicle are controlled via data connections or bus systems. Known buses used in motor vehicles are, for example, LIN (Local Interconnect Network) buses, CAN (Controller Area Network) buses or FlexRay buses, and discrete signals can also be transmitted in a cable harness that runs through the entire vehicle. These buses are generally designed according to function, i.e., controllers that form a common function are connected to one bus.

[0003] The LIN system consists of a master (LIN master) and one or more slaves (LIN slaves). The master is, for example, a microcontroller, which can, for example, act as a bridge to connect LIN to a CAN bus. On LIN, the master determines the (e.g. fixedly configured) time sequence of all messages by sending the beginning of the message (the so-called header). Therefore, one or more LIN slaves are serially connected to the LIN master via the LIN bus. The transmission protocol stipulates that a header is sent from the LIN master to the LIN slave. As a response to the header, the responding LIN slave sends a response back to the LIN master within a specified time slot (e.g. within a 5ms or 10ms clock on the LIN bus). The header and the response are combined into a frame, which is sent for the duration of the specified time slot.

[0004] In controllers for controlling multiple devices or slaves with different functions, when using LIN buses, more and more LIN buses are required in motor vehicles, which are arranged as transmission cables in the cable harness of the vehicle. Due to the large number of LIN buses, the circumference or cross-section of the cable harness may be large, so that the cable harness may be difficult to place in the limited space of the motor vehicle. Summary of the invention

[0005] The object of the present disclosure is to provide an improved concept for transmitting signals for controlling slaves in a local network, for example in a vehicle.

[0006] This object is achieved by means of a system according to the disclosure for data transmission in a motor vehicle, a method according to the disclosure for controlling a LIN slave connected to a LIN bus, and a motor vehicle according to the disclosure.

[0007] Accordingly, a system for data transmission in a motor vehicle is proposed. The system comprises a central controller in which at least one LIN master is configured. In addition, at least one local controller is provided, which is coupled to the central controller by means of a first data connection.

[0008] The local controller is also coupled to a LIN bus assigned to a LIN master, to which at least one LIN slave is connected. In particular, it is provided that a plurality of LIN slaves are connected to the LIN bus and can be controlled by means of a respectively assigned LIN master arranged in the central controller. It is provided that the data transmission speed of the first data connection between the central controller and the local controller is higher than the data transmission speed of the LIN bus. The higher data transmission speed enables the same amount of data to be transmitted in a shorter time via the first data connection than via the LIN bus.

[0009] Compared to the LIN bus, the higher data transmission speed of the first data connection enables a faster exchange of header information (e.g. for transmission as a header via the LIN bus) and response information (e.g. already transmitted as a response via the LIN bus) between the central controller and the local controller. For example, in this way, a plurality of header information can be transmitted via the first data connection during a predefined time slot of a LIN bus. This is advantageous if a plurality of LIN buses are connected to the local controllers, which are controlled by a respective LIN master of the central controller.

[0010] The proposed system enables, for example, that information from a LIN master, which is to be transmitted via a LIN bus, can first be sent via a faster connection to a local controller, from which the information is further transmitted on the slower LIN bus. Thus, in contrast to conventional systems, provision is made for the LIN master not to be arranged directly in the local controller, but in a separate central controller.

[0011] By using the faster first data connection, for example, multiple transmission cables of multiple LIN buses can be omitted between the central controller and the local controllers compared to conventional systems, because the header information and response information of multiple LIN buses can be transmitted, for example, via a common transmission cable of the first data connection. This can be done, for example, without causing time delays when controlling corresponding devices on different LIN buses. For example, by using the first data connection, the cable bundle between the central controller and the local controllers can be advantageously reduced (for example, the cable bundle has a smaller diameter or a smaller cross-sectional area).

[0012] According to one embodiment, it is provided that the LIN master and / or LIN slave is hardware-supported on a microcontroller used for this purpose. In general, functions can be implemented on a microcontroller by means of software or by using predetermined hardware blocks. A software solution can have the advantage that it can be changed more flexibly or can execute multiple functions, whereas a physical hardware block can only be used for the corresponding specified functions once it has been implemented. In this regard, in a hardware-supported embodiment, for example, the required execution time can be adhered to more accurately (for example, the process duration can be better planned), because, for example, no other processes can delay the execution (for example, as in a software solution).

[0013] When transmitting LIN information (e.g. frames; e.g. headers and responses), tolerance times are specified in each case according to the LIN transmission standard. The transmission time actually required (e.g. maximum header transmission time) can be up to 40% longer than the nominal transmission time. Therefore, when using fixed time slots (e.g. 5ms or 10ms time slots) as specified during transmission via the LIN bus, if the transmission mechanism in effect does not require the reserved tolerance time, an idle time window is generated in the time slot of the frame. When a hardware-supported microcontroller is used to implement a LIN master and / or LIN slave, it can be achieved that the nominal transmission time is adhered to or at least the entire reserved tolerance time is not required. Therefore, the unnecessary tolerance time (e.g. time window) in the time slot of the LIN bus can be fully utilized in other aspects.

[0014] The microcontroller supported by hardware can be realized with higher reliability without the need for a prescribed time window (tolerance time) on the LIN bus. In this time window, header information and / or response information can be advantageously transmitted from or to the LIN host via the first data connection, without, for example, delaying the prescribed clock on the LIN bus. When implementing the LIN function on a modern microcontroller with LIN stack hardware support, for example, a 40% reservation or tolerance time interval in the timing is not required or not completely required. Such time can be used, for example, for tunnel transmission (Tunneln) of (for example, header information and response information via the first data connection). The available idle time window has, for example, the length of the time slot duration (that is, the nominal transmission time of the header and response multiplied by a coefficient of 140%) minus the nominal transmission time of the header and response (for example, the maximum tolerance time). However, for example, according to the data transmission speed of the first data connection, a shorter time window (for example, shorter than the maximum tolerance time) may also be sufficient for transmitting header information and / or response information from or to the LIN host via the first data connection.

[0015] As an alternative or in addition to the use of a hardware-supported microcontroller, the availability of the idle time window can be better ensured, for example also when the software solution is used on a high-performance computing unit or on a computing unit provided specifically for the software solution.

[0016] For example, when using the proposed system, it is possible to transmit information via the first data connection (e.g. from or to a LIN master associated with the LIN bus) also within a specified time slot of the LIN bus. According to one embodiment, it is provided that the system is designed to transmit both the frame via the LIN bus and the header information and response information corresponding to the frame via the first data connection within the duration of a predefined nominal time slot for data transmission of frames via the LIN bus (i.e. headers and responses transmitted via the LIN bus).

[0017] In other words, the unneeded tolerance times defined by the LIN transmission standard can be used to transmit (e.g., tunnel) header information and / or response information via the first data connection (which can be referred to as a trunk bus, for example). This makes it possible that the corresponding header information and / or response information can also be transmitted from or to the LIN master arranged in the central controller during the time slot duration on the LIN bus.

[0018] Accordingly, according to an example, the system is configured to exchange response information (e.g., response information of the same LIN frame assigned with the tolerance time) and header information (e.g., header information of the next LIN frame) between the LIN master and the local controller via the first data connection within the tolerance time of the LIN frame specified according to the LIN standard. Therefore, the LIN protocol can be executed without delay even if the header information and the response information still have to be sent to the LIN master via the first data connection. Advantageously, delay-free LIN communication can be performed via the first data connection even when the LIN bus is separated from the LIN master. In other words, every time slot of a LIN frame on the LIN bus can be used by the LIN master in the central controller. Due to the fast data transmission of the first data connection, the response information can already be present in the LIN master within the tolerance time that is not required according to the LIN protocol before the LIN frame has ended in time. In response to the received response information, the LIN master can then send another header information to the decentralized LIN slaves, so that the other header information can also already be present on the local controller before the LIN frame has ended in time (see also the disclosure of the present invention). Figure 5 In this way, delay-free LIN communication can be advantageously combined with the flexibility of a decentralized system.

[0019] According to one embodiment, the central controller comprises a plurality of LIN masters and the local controllers are coupled to a plurality of LIN buses. As already mentioned above, by means of a faster first data connection and / or the use of idle time windows in time slots, it can be achieved, for example, that the data transmission of header information and / or response information between the LIN masters of the central controller and the corresponding LIN buses can be carried out via a common first data connection, so that, for example, the cable requirements of the system can be reduced.

[0020] According to one embodiment, the system further comprises at least one second local controller, which is also coupled to the central controller by means of a first data connection, like the previously described (e.g. first) local controller. For example, a more decentralized distribution of the local controllers enables better cabling (e.g. a shorter total length of the LIN bus cable).

[0021] According to one embodiment, it is provided that the data transmission speed of the first data connection corresponds to at least 10 times (or 20 times or 50 times) the data transmission speed of the LIN bus. This faster transmission speed on the first data connection makes it possible, for example, to operate a larger number of LIN buses with the aid of a LIN master arranged in a central controller. For example, it is also possible to transmit other information (for example additional and / or information other than header information and response information) via the first data connection, without, for example, conflicts or delays occurring in the transmission via the first data connection.

[0022] According to one embodiment, the first data connection is configured according to the Ethernet standard, the CAN standard, the FlexRay standard, a radio-based transmission standard (such as WLAN or Bluetooth) or a home network standard (such as HomeGrid-G.hn). Using these standards, the data transmission speed required for the first data connection can be achieved.

[0023] Another aspect relates to a method for controlling a LIN slave connected to a LIN bus. The method can be implemented, for example, using the system described above or below. The method comprises: sending header information from a LIN master of a central controller to a local controller via a first data connection between the central controller and the local controller. In this case, the first data connection has a higher data transmission speed than the LIN bus. The method also comprises: receiving the header information at the local controller and sending the header information to the LIN slave via the LIN bus connected to the local controller.

[0024] For example, it is provided that the method further comprises: receiving, at the local controller, response information of the LIN slave corresponding to the header information, and sending the response information from the local controller to the LIN master of the central controller via the first data connection.

[0025] Thus, according to the method, for example, a LIN slave, which is connected to a local controller via a LIN bus, can be advantageously controlled by means of a LIN master arranged in a central controller. By using a faster first data connection, for example, header information and / or response information can be transmitted more quickly, so that the first data connection can be used jointly to control a plurality of LIN buses. Thus, for example, the cable requirements required for controlling devices on the LIN bus can be reduced overall.

[0026] For example, a predetermined time slot (e.g. a 5 ms or 10 ms time slot according to the LIN transmission specification) can be used to transmit header information and response information (e.g. a LIN frame) via the LIN bus. In addition, it is provided that the response information and / or the further header information is sent via the first data connection within a time window reserved in the time slot. The availability of the time window can be achieved in such a way that the tolerance time reserved in the time slot according to the LIN standard is not required for the transmission on the LIN bus. As already described, this can be achieved, for example, by using a hardware-based microcontroller when implementing the LIN master and / or the LIN slave.

[0027] For example, it can be provided that the header is transmitted on the LIN bus at the beginning of a time slot. Thus, an idle time window can be provided at the end of a time slot. Before the time window in the time slot is reached, a response can be received at the local controller via the LIN bus, so that the corresponding response information can be sent to the LIN master via the first data connection within the idle time window. In order to be able to send the corresponding next header via the LIN bus in the next time slot, for example, the header information for the next time slot is also sent to the local controller via the first data connection within the time window (see also in conjunction with Figure 5 In summary, header information and response information of a frame (e.g. a LIN bus frame) can be sent from the LIN master via the first data connection within a defined duration of a time slot (e.g. delayed relative to the actual time slot on the LIN bus) and received again at the LIN master. Thus, even when using the first data connection, time delays when controlling the LIN slaves can be avoided.

[0028] According to one embodiment, the reserved time window has a duration of at least 0.2 ms (or at least 0.5 ms, at least 1 ms, at least 1.5 ms or at least 2 ms) and / or at most 5 ms (or at most 4 ms or at most 3.5 ms). During this time, for example, header information and / or response information can be transmitted via the first data connection between the central controller and the local controller.

[0029] According to one embodiment, the method further comprises: sending a second header message from a second LIN master of the central controller via the first data connection. The two header messages are sent in a time-staggered manner with a time offset, which is selected according to the data transmission speed of the first data connection.

[0030] The first header information is sent to the LIN slaves on the first LIN bus, while the second header information, which is offset in time, is sent to the LIN slaves on the second LIN bus (the second LIN bus is, for example, coupled to the same or another local controller). Since the data transmission speed of the first data connection is greater than the data transmission rate of the LIN bus, the two header information can be transmitted on a common data line. By using the time offset, conflicts of the header information on the first data connection can be avoided.

[0031] For example, a time offset of at least 20 μs (or at least 50 μs or at least 100 μs) can be selected between the transmission of two header information via the first data connection. For example, the time offset can also be selected such that the corresponding response information can be transmitted back to the corresponding LIN master via the first data connection without colliding with subsequent header information on the first data connection. This can avoid waiting times due to conflicts, for example.

[0032] According to one embodiment, it is provided that the header information is embedded in a standard data packet of the first data connection when it is sent via the first data connection. The first data connection can be, for example, a CAN bus and the header information can be embedded in a CAN frame. Accordingly, the response information can also be embedded in a corresponding data packet of the standard used. Advantageously, when transmitting via the first data connection, for data packets of variable length, a frame size as small as possible can be selected in which the header information and / or the response information can be transmitted (for example, the standard minimum available frame size of the first data connection).

[0033] For example, an Ethernet connection can be used as the first data connection, and the header information and / or the response information are embedded in a 64-byte Ethernet frame when transmitted via the Ethernet connection. The advantage can be that the header information and the response information (for example, in the case of data being sent by the host itself) can each be completely transmitted in a 64-byte Ethernet frame and the transmission time via the first data connection can be very short. For example, an Ethernet connection with a maximum of 10 Mbit / s can be used, because this allows sufficiently fast data transmission and / or allows a more economical design of the first data connection.

[0034] Another aspect relates to a motor vehicle having a system as described above or below. In particular, it is provided that a transmission cable of a first data connection and / or a LIN bus is laid through a vehicle pillar of the motor vehicle. For example, a transmission cable of a first data connection (for example a CAN bus or Ethernet cable) can be laid through the vehicle pillar, so that a plurality of LIN bus cables in the vehicle pillar can be omitted. For example, the system makes it possible that not all LIN bus cables of the system have to be laid through the vehicle pillar, but rather the number of LIN bus cables in the vehicle pillar can be limited. This can advantageously make it easier to thread a cable harness through the vehicle pillar, for example.

[0035] Alternatively, the proposed system can also be used for other vehicles (for example air vehicles or water vehicles) and can generally be used in local networks (for example smart home devices or home networks such as defined by the HomeGrid standard).

[0036] One aspect relates to a system for data transmission. The system comprises a central controller in which at least one master of a bus (e.g. a serial bus) is constructed. In addition, at least one local controller is provided, which is coupled to the central controller by means of a first data connection. The local controller is also coupled to a bus of the master assigned to the bus, to which at least one slave of the bus is connected. It is provided that the data transmission speed of the first data connection between the central controller and the local controller is higher than the data transmission rate of the bus. The bus can be, for example, a LIN bus, a CAN bus or a FlexRay bus. The first data connection can be, for example, an Ethernet connection.

[0037] Other details and aspects are mentioned in conjunction with the embodiments described above or below. The described embodiments may have one or more optional additional features, which correspond to the combination of the proposed design or the combination of the above or below (such as Figures 1 to 6 ) One or more aspects mentioned in one or more embodiments described in the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] The following is a more detailed description of the embodiments with reference to the accompanying drawings.

[0039] Figure 1 shows a schematic example of a system having a central controller and local controllers;

[0040] Figure 2 A schematic example of a system with two local controllers is shown;

[0041] FIG3 shows an example of a conventional system having a LIN bus;

[0042] Figure 4A flow chart showing a method for controlling a LIN slave;

[0043] Figure 5 shows an example of transmitting header information and response information via the first data connection and the LIN bus; and

[0044] Figure 6 An example is shown of the transmission of a plurality of frames to a plurality of LIN buses via a first data connection using a time offset. DETAILED DESCRIPTION

[0045] Various embodiments are now described in more detail with reference to the accompanying drawings, in which some embodiments are shown. In the accompanying drawings, the thickness dimensions of lines, layers and / or regions may be exaggerated for clarity. In the following description of the drawings showing only a few exemplary embodiments, the same reference numerals may represent the same or similar components.

[0046] An element that is said to be "connected" or "coupled" to another element may be directly connected or coupled to the other element, or there may be an intervening element. Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as given to them by one of ordinary skill in the art to which the embodiments belong.

[0047] Figure 1 A schematic example of a system 10 is shown having a central controller 11 and a local controller 12. The central controller 11 and the local controller 12 are connected by means of a first data connection 13. Furthermore, at least one bus, in particular a LIN bus 14, is connected to the local controller 12, which has at least one slave, in particular a LIN slave 15a. The LIN bus 14 and the LIN slave 15a are associated with a master, in particular a LIN master 11a, which is arranged in the central controller 11. The system 10 can be used, for example, in a motor vehicle.

[0048] By providing the first data connection 13 with a higher data transmission speed than the LIN bus, for example, more LIN buses can be connected to the local controller 12 without having to lay their transmission cables separately to the central controller 11 with the corresponding LIN master. As a result, the system 10 can reduce the need for cables when using multiple LIN buses.

[0049] For example, the first data connection 13 can be used as a central data connection (such as a central bus or a backbone bus) in order to tunnel header information and response information from a corresponding LIN bus to an associated LIN master in the central controller 11 .

[0050] Alternatively, instead of the LIN bus, another bus system can also be provided which has a lower data transmission speed than the first data connection 13 .

[0051] Further details and aspects are mentioned in conjunction with the embodiments described above or below. Figure 1 The embodiments shown in the figure may have one or more optional additional features, which correspond to the additional features in combination with the proposed design or in combination with the above or below (for example Figures 2 to 6 ) One or more aspects mentioned in one or more embodiments described in the present invention.

[0052] Figure 2 A schematic example of a system 10 with two local controllers 12, 12b is shown. Here, a plurality of LIN masters 11a, 11b, 11n are arranged in a central controller 11. Three LIN masters (including LIN masters 11a, 11b) can be used to control LIN buses 14, 14b, 14c connected to the first local controller 12. Other LIN masters (including LIN master 11n) can be used to control LIN buses 14d, 14n connected to the second local controller 12b.

[0053] For example, the two local controllers 12, 12b can be arranged at different locations, which are respectively closer to the LIN slaves associated with the LIN bus. As a result, the required cable length of the LIN bus 14, 14b, 14c, 14d, 14n can be further reduced overall, because the two local controllers 12, 12b can share the first data connection 13. For example, further local controllers can be coupled to the first data connection 13 in a similar manner.

[0054] Further details and aspects are mentioned in conjunction with the embodiments described above or below. Figure 2 The embodiments shown in the figure may have one or more optional additional features, which correspond to the additional features in combination with the proposed design or in combination with the above (for example Figure 1 ) or below (e.g. Figures 3 to Figure 6 ) One or more aspects mentioned in one or more embodiments described in the present invention.

[0055] FIG3 shows an example of a conventional system according to the prior art with a plurality of LIN buses 140, 140b, 140n. All LIN buses 140, 140b, 140n are directly connected to a controller 110, in which a corresponding LIN master 110a, 110b, 110h corresponding to each bus is provided. Compared to the proposed system 10, the demand for transmission cables increases with each additional LIN bus, since no common transmission cable can be used for a plurality of LIN buses.

[0056] Figure 4 A flow chart of a method 30 for controlling a LIN slave is shown. The method 30 comprises sending 31 header information from a LIN master of a central controller to a local controller via a first data connection between the central controller and the local controller. In this case, a first data connection having a higher data transmission speed than the LIN bus is used. The method 30 also comprises receiving 32 the header information at the local controller and sending 33 the header information to the LIN slave via the LIN bus connected to the local controller.

[0057] Method 30 makes it possible to transmit header information for a plurality of LIN buses via a common data channel, namely the first data connection, whereby, for example, the required cabling requirements can be reduced.

[0058] Further details and aspects are mentioned in conjunction with the embodiments described above or below. Figure 4 The embodiments shown in the figure may have one or more optional additional features, which correspond to the additional features in combination with the proposed design or in combination with the above (for example Figure 1 to Figure 3) or below (e.g. Figure 5 to Figure 6 ) One or more aspects mentioned in one or more embodiments described in the present invention.

[0059] Figure 5 The first data connection 13 (eg CAN bus, see Figure 5 The upper half of FIG. 80 is used to transmit the header information H and the response information R via the LIN bus 14 (see FIG. 80 ). Figure 5 The lower half of the time slot 80 transmits a frame including a header (header information H) and a response or a slave response (response information R). The length shown of the time slot 80 is purely exemplary and, for example, instead of the 10 ms shown, it can also be 5 ms or another duration.

[0060] It can be seen that the first part of the time slot 80 is sufficient for transmitting the header information H and the response information R via the LIN bus 14, so that an idle time window 81 until the start of the next time slot is generated or can be used. The duration of the time window is, for example, about 33% of the duration of the time slot 80 (for example, at most 40% and / or at least 20% of the duration of the time slot 80). If the tolerance time defined in the LIN transmission standard is not needed for transmitting the LIN frame, the idle time window 81 can be provided. The idle time window 81 can therefore also be called tolerance time 81.

[0061] The idle time window 81, in which no information transmission takes place via the LIN bus 14, can be used to transmit a response message R back to the LIN master in the central controller via the first data connection 13 (e.g. tunnel the response message R). In addition, a further header message H is used to transmit a header via the LIN bus 14 in the next time slot. n+1 The LIN master can send a response message R to the local controller via the first data connection 13. The header information R for the LIN frame of the time slot 80 shown has already been transmitted in the free time window of the previous time slot (see the header signal H on the first data connection 13 before the start of the time slot 80). The time period from the sending of the header information H via the first data connection 13 to the end of the reception of the associated response information R via the first data connection 13 can therefore take place within a time period that is shorter than the time period of the time slot 80.

[0062] Further details and aspects are mentioned in conjunction with the embodiments described above or below. Figure 5 The embodiments shown in the figure may have one or more optional additional features, which correspond to the additional features in combination with the proposed design or in combination with the above (for example Figures 1 to 4 ) or below (e.g. Figure 6 ) One or more aspects mentioned in one or more embodiments described in the present invention.

[0063] Figure 6 The time offset t is shown in off Example of transmitting a plurality of frames f1, f2, f3 via the first data connection 13 to a plurality of LIN buses 14, 14b, 14c in the case of off For example, the duration between the start of the first header information H and the start of the next header information H2 can be described. For example, the transmission of the header information via the first data connection 13 can last for 50 to 60 μs and the time offset t off For example, the time offset t off The duration between the end of the transmission of the header information H and the start of the transmission of the header information H2 can be defined and can be, for example, greater than 10 μs and / or less than 50 μs.

[0064] The header information H, H2, H3 is sent from different LIN masters in sequence via the first data connection 13 to different LIN buses 14, 14b, 14c respectively associated with the LIN masters. It can be seen that the slower data transmission of the frames f1, f2, f3 via the LIN buses 14, 14b, 14c requires longer time than the data transmission of the header information and the response information via the first data connection 13. Therefore, after the first header information H is sent from the first LIN master, further header information H2, H3, etc. can be sent from other LIN masters via the first data connection 13, for example during the transmission of the frame f1 via the LIN bus 14. For example, the maximum possible number of header information H, H2, H3, etc. that can be sent via the common data connection 13 can depend on the data transmission speed and / or the time offset t off The length of and / or the duration of frame f1. For example, the time offset t can be selected as follows off , so that between sending two consecutive header information, a corresponding response information can be transmitted via the first data connection 13, so as to achieve, for example, continuous alternating transmission of header information and response information via the first data connection 13.

[0065] With offset t off The synchronization of the LIN masters can, for example, enable conflict-free scheduling on the trunk bus (e.g., the first data connection 13). For example, the time slots of the LIN buses 14, 14b, 14c are each arranged with a time offset. The use of synchronization or time offset makes it possible for the multiple LIN masters to continuously send further headers of subsequent LIN frames for the associated LIN buses 14, 14b, 14c via the first data connection 13 without conflicts occurring on the first data connection 13.

[0066] Further details and aspects are mentioned in conjunction with the embodiments described above or below. Figure 6 The embodiments shown in the figure may have one or more optional additional features, which correspond to the additional features in combination with the proposed design or in combination with the above (for example Figures 1 to 5 ) or one or more aspects mentioned in one or more embodiments described below.

[0067] The example relates to a method for tunneling a LIN bus 14 via a trunk bus, for example a first data connection 13, such as a CAN bus or an Ethernet connection. In order to be able to, for example, produce cable harnesses more slenderly, more cheaply and / or more automatically, one or more trunk buses (such as the first data connection) are introduced, via which buses such as LIN, CAN, FlexRay and discrete signals can be tunneled.

[0068] In particular, the tolerances present in the LIN specification can be fully utilized here. In modern available microcontrollers (μCs) with hardware LIN logic (such as hardware support), for example, these tolerances (such as idle time window 81) are no longer required on the LIN bus. The LIN masters of the LIN buses that are to be tunneled together can be synchronized by a time offset. For example, a time buffer (such as time window 81) is provided for the tunneling of the LIN bus. In the case of tunneling multiple LIN buses on the same trunk bus, conflicts can be avoided with the help of the proposed design. For example, multiple LIN buses can be laid from a central controller to a rear controller and / or a roof controller.

Claims

1. A system (10) for data transmission in a motor vehicle, the system (10) comprising: A central controller (11), in which at least one LIN host (11a) is constructed; and at least one local controller (12) which is coupled to the central controller (11) by means of a first data connection (13), The local controller (12) is also coupled to a LIN bus (14) provided to a LIN master (11a), to which at least one LIN slave (15a) is connected, and The data transmission speed of the first data connection (13) between the central controller (11) and the local controller (12) is higher than the data transmission speed of the LIN bus (14), The system (10) is designed to exchange response information (R) and / or further header information (H) between a LIN master (11a) and a local controller (12) via a first data connection (13) within a reserved time window (81) of a LIN frame specified in accordance with the LIN standard. n+1 ).

2. The system (10) according to claim 1, wherein: The LIN master (11a) and / or the LIN slave (15a) are designed to be hardware-supported on a microcontroller used for this purpose.

3. The system (10) according to claim 1 or 2, wherein: The system (10) is designed to transmit frames (f1, f2) via the LIN bus (14) and to transmit header information and response information corresponding to the frames (f1, f2) via the first data connection (13) within the duration of a predefined nominal time slot (80) for data transmission of frames (f1, f2) via the LIN bus (14).

4. The system (10) according to claim 1 or 2, wherein: The system further comprises at least one second local controller which is coupled to the central controller (11) by means of the first data connection (13).

5. The system (10) according to claim 1 or 2, wherein: The central controller (11) includes a plurality of LIN masters, and the local controller (12) is coupled to a plurality of LIN buses.

6. The system (10) according to claim 1 or 2, wherein: The data transmission speed of the first data connection (13) is at least 10 times greater than the data transmission speed of the LIN bus (14).

7. The system (10) according to claim 1 or 2, wherein: The first data connection (13) is designed according to the Ethernet standard, the CAN standard, the FlexRay standard, a radio-based transmission standard or a home network standard.

8. A method (30) for controlling a LIN slave (15a) connected to a LIN bus (14), the method comprising: sending (31) header information (H) from a LIN master (11a) of the central controller (11) to the local controller (12) via a first data connection (13) between the central controller (11) and the local controller (12), the first data connection (13) having a higher data transmission speed than the LIN bus (14); Receiving (32) said header information (H) at a local controller (12); Sending (33) the header information (H) to the LIN slave (15a) via a LIN bus (14) connected to the local controller (12); receiving, at the local controller (12), a response message (R) from the LIN slave (15a) corresponding to the header message (H); and sending the response message (R) from the local controller (12) to the LIN master (11a) of the central controller (11) via the first data connection (13), wherein a predetermined time slot (80) is used to transmit header information (H) and response information (R) via a LIN bus (14), Sending a response message (R) and / or another header message (H) via the first data connection (13) within a time window (81) reserved in the time slot (80) n+1 ).

9. The method (30) according to claim 8, wherein: The reserved time window (81) has a duration of at least 0.5 ms.

10. The method (30) according to claim 8 or 9, wherein: The method further comprises: A second header message (H2) is sent from the second LIN master of the central controller (11) via the first data connection (13), wherein the two header messages are time-shifted (t off ) are sent in a time-shifted manner, the time shift being selected as a function of the data transmission speed of the first data connection (13).

11. The method (30) according to claim 8 or 9, wherein: The header information (H) is embedded in a standard data packet of the first data connection (13) when it is sent via the first data connection (13).

12. The method (30) according to claim 8 or 9, wherein: An Ethernet connection is used as the first data connection (13), and the header information (H) and / or the response information (R) are embedded in a 64-byte Ethernet frame when transmitted via the Ethernet connection.

13. A motor vehicle having a system (10) according to any one of claims 1 to 7, wherein: The transmission cable of the first data connection (13) and / or the LIN bus (14) is laid through a vehicle pillar of the motor vehicle.

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