Network in a motor vehicle, control unit and procedures

Abstract

The invention relates to a network (1) in a motor vehicle, wherein the network comprises n control units (2), wherein the control units (2) have software (7) configured to generate data for a first diagnostic standard and a second diagnostic standard, wherein the control units (2) have at least one local memory area (8, 9), wherein the control units (2) are interconnected via at least one bus system (4), wherein the control units (2) each have protocol software (11, 12) for the first diagnostic standard and for the second diagnostic standard, wherein one control unit (2) is configured as a master (3) to determine the protocol software (11, 12) to be used by the other control units (2), a control unit (2) and a method for generating diagnostic data.

Description

[0001] The invention relates to a network in a motor vehicle, a control unit and a method for generating diagnostic data in a network.

[0002] The networks in a motor vehicle consist of numerous electronic control units (ECUs) that communicate with each other via at least one bus system. These ECUs have memory in which status or error messages can be stored. This data can then be read from outside the vehicle, for example, by customer service or an enforcement agency such as the police. Protocol software is used to transmit the data from the memory to the external tester via the bus system. The data volume for customer service and the enforcement agency may differ. For example, the data for customer service might include additional diagnostic information that is not relevant to the enforcement agency.

[0003] Furthermore, various diagnostic standards such as OBD or OBD on UDS are known, with the latter being legally required in some countries. Accordingly, the correct software must be available to comply with the respective legal regulations.

[0004] This complicates the manufacturing process, as the control units must be programmed with the correct software.

[0005] The invention addresses the technical problem of creating a network in a motor vehicle that is more easily adaptable to different diagnostic standards. A further technical problem is the creation of a suitable control unit and the provision of a method for generating diagnostic data.

[0006] The solution to the technical problem is achieved by a network having the features of claim 1, a control unit having the features of claim 7, and a method having the features of claim 8. Further advantageous embodiments of the invention are set forth in the dependent claims.

[0007] The network in a motor vehicle comprises n electronic control units (ECUs). These ECUs contain software configured to generate data for a first diagnostic standard and a second diagnostic standard. Furthermore, each ECU has at least one local memory area. The ECUs are interconnected via at least one bus system. Each ECU contains protocol software for the first diagnostic standard and for the second diagnostic standard, with one ECU acting as the master, determining the protocol software to be used by the other ECUs. This allows for the installation of ECUs with identical software configurations, as the master only needs to specify, for example, at the end of the production line, which protocol software should be used. This avoids the need for complex program modifications. In principle, it is also possible to support more than two diagnostic standards.

[0008] In one embodiment, the control units have at least two local memory areas, wherein the data of the first diagnostic standard is written to the first memory area and the data of the second diagnostic standard to the second memory area, wherein the at least two memory areas are preferably designed as separate memory modules. This keeps the data for the different diagnostic standards separate, and the protocol software selected by the master accesses the respective assigned memory area when reading it. This allows for a very simple separation of the two diagnostic standards and simplifies protection against manipulation.

[0009] In another embodiment, the control units have at least one memory area in which at least some data for the first diagnostic standard and the second diagnostic standard are stored at a common memory address, with the first and second protocol software reading at least partially different bits. This takes advantage of the fact that there are some data points that are identical in most places for the OBD and OBD on UDS diagnostic standards, with OBD on UDS only having additional bits. Depending on the protocol software used, these additional bits are then either read or not. This saves memory space.

[0010] In another embodiment, the control unit has a mapping algorithm designed to generate data for the respective diagnostic standard from internal measured variables. This also allows for the use of a shared memory.

[0011] In another embodiment, the software of the control units is designed to generate and store the data for the first diagnostic standard and the second diagnostic standard, regardless of the protocol software used.

[0012] Regarding the design of the control unit and the procedure, full reference is made to the preceding statements.

[0013] The invention is explained in more detail below with reference to a preferred embodiment. The single figure shows a schematic representation of a network in a motor vehicle.

[0014] In the Fig.Figure 1 schematically depicts a network 1 in a motor vehicle. The network 1 comprises n control units 2, where one control unit 2 is a master 3. The control units 2 are interconnected via at least one bus system 4. The master 3 is, for example, an engine control unit, and the bus system 4 is, for example, a CAN bus. In addition to their normal functions, the control units also have diagnostic functions, with an area 5 for customer service and an area 6 for control instances. The control units 2 have software 7 that can generate data for a first diagnostic standard and a second diagnostic standard. The first diagnostic standard is, for example, a classic OBD, and the second diagnostic standard is, for example, OBD on USD. The control units 2 have a first memory area 8 and a second memory area 9, which are configured as separate memory modules 10.Furthermore, the control units 2 have protocol software 11 for the first diagnostic standard and protocol software 12 for the second diagnostic standard. Finally, network 1 has an interface for connecting an external tester 13 (e.g., a GST Generic Scan Tool) to bus system 4. The control unit 2, which has been selected as master 3, knows at the end of the assembly line for which country the vehicle is intended. The control unit 2, operating as master 3, then sends this information via bus system 4 to the other control units 2. It is assumed that the second diagnostic standard is legally mandatory in that country. In this case, the first protocol software 11 is deactivated (shown with a dashed line), and the second protocol software 12 is activated. During operation, the control units 2 then write diagnostic data according to the second diagnostic standard into their respective second memory area 9.When a tester 13 is connected to read diagnostic data according to the second diagnostic standard, it receives a request via the second protocol software 12. This request is read by the control units 2, and the requested data from the second memory area 9 is transmitted to the tester 13 via the bus system 4 using the second protocol software 12. Requests from a tester 13 using the first protocol software 11 to transmit diagnostic data from area 6 are ignored. Reference symbol list 1 Network 2 Control unit 3 Master 4 bus system 5 area for 6 Area for control bodies 7 Software 8 first memory area 9 second memory area 10 memory modules 11 Protocol software 12 Protocol software 13 testers

Claims

[1] Network (1) in a motor vehicle, wherein the network comprises n control units (2), wherein the control units (2) comprise software (7) configured to generate data for a first diagnostic standard and a second diagnostic standard, wherein the control units (2) comprise at least one local memory area (8, 9), wherein the control units (2) are interconnected via at least one bus system (4), wherein the control units (2) each comprise protocol software (11, 12) for the first diagnostic standard and for the second diagnostic standard, wherein one control unit (2) is configured as a master (3) to determine the protocol software (11, 12) to be used by the other control units (2). [2] Network according to claim 1, characterized by, that the control units (2) have at least two local memory areas (8, 9), wherein the data of the first diagnostic standard are written to the first memory area (8) and the data of the second diagnostic standard are written to the second memory area (9). [3] Network according to claim 2, characterized by , that the at least two memory areas (8, 9) are designed as separate memory modules (10). [4] Network according to one of the preceding claims, characterized by , that the control units (2) have at least one memory area in which at least individual data for the first diagnostic standard and the second diagnostic standard are stored at a common memory address, wherein the first and second protocol software (11, 12) read different bits. [5] Network according to claim 1, characterized by, that the control unit (2) has a mapping algorithm designed to generate data for the respective diagnostic standard from internal measured variables. [6] Network according to any one of claims 1 to 4, characterized by , that the software (7) of the control units (2) is designed to generate and store the data for the first diagnostic standard and the second diagnostic standard, regardless of the protocol software (11, 12) used. [7] Control unit (2) for a network in a motor vehicle, wherein the control unit (2) has software (7) configured to generate data for a first diagnostic standard and a second diagnostic standard, wherein the control unit (2) has at least one memory area (8, 9), wherein the control unit (2) has a connection for a bus system (4) and has protocol software (11, 12) for the first diagnostic standard and the second diagnostic standard. [8] Method for generating diagnostic data in a network (1) of a motor vehicle, wherein the network (1) comprises n control units (2), wherein the control units (2) have software (7) that can generate data for a first diagnostic standard and a second diagnostic standard, wherein the control units (2) have at least one local memory area (8, 9), wherein the control units (2) are interconnected via at least one bus system (4), wherein the control units (2) each have protocol software (11, 12) for the first diagnostic standard and for the second diagnostic standard, wherein a control unit (2) as master (3) determines the protocol software (11, 12) to be used for all control units (2), via which the generated data can then be read out from the outside.

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