WO2002089420A2

WO2002089420A2 - Device for generating a messaging system common to several electronic systems producing and consuming data

Info

Publication number: WO2002089420A2
Application number: PCT/FR2002/001453
Authority: WO
Inventors: Samuel Boutin; Damien Couderc
Original assignee: Renault S.A.S.
Priority date: 2001-04-27
Filing date: 2002-04-26
Publication date: 2002-11-07
Also published as: DE60215926T2; WO2002089420A3; FR2824213B1; DE60215926D1; FR2824213A1

Abstract

The data are exchanged on a multiplexed communication bus (B) interconnecting the systems (Sn), the data being carried by digital signal frames. The device comprises: a) means (In) for listing the data produced or consumed by the systems (Sn) and the characteristics of said data; b) means (MC) for configuring the signal frames produced by each of the systems, said means including: b1) means (LI) for reading the content of the data listing means (In), b2) means (MF) for constituting frame formats, from data assembled by the reading means (LI) and predetermined rules; and c) means (Fn) for loading, in each of the systems (Sn), frame formats constituted by the formatting means (MC) so as to transmit data-loaded frames. The invention is applicable to a motor vehicle.

Description

Device for generating messaging common to several electronic systems producing and consuming data

The present invention relates to a device for generating messaging common to several electronic systems producing and consuming data exchanged on a common multiplex communication bus, said data being carried by digital signal frames each comprising at least one of said data. .

There are known sets of electronic systems of this type, designed in particular to equip motor vehicles. Such a vehicle commonly comprises several systems, each ensuring the execution of a service such as controlling the engine propelling the vehicle, managing the air conditioning of the passenger compartment, managing the connections of the vehicle to the ground (braking, suspension, etc.). .), management of telephone communications, etc., etc.

The material means which constitute all of these systems are shown diagrammatically in FIG. 1 of the attached drawing. These means essentially comprise electronic control units or "ECUs" UCE _{n /} each computer possibly being connected to sensors C ⁿ ι and to actuators A ¹ "- ,, all the computers being connected to the same bus B to transmit there. or receive suitably ultiplexed information from or to the other computers connected to bus B.

This multiplexing is obtained in particular, as is well known for the CAM bus for example, by introducing the information in question in messages materialized by digital signal frames comprising in particular an "identifier field" of said frame and a "data field "commonly gathering several pieces of information of different natures (value of a physical quantity, state of an organ, etc.) each contained in a predetermined part of this field. By way of illustrative example, the system S ₂ of "engine control" comprises the computer ^• UCE ₂ , several sensors C ² i sensitive to quantities such as the engine speed, for example of internal combustion, the pressure at the manifold intake of this engine, outside air pressure, engine cooling water temperature, air temperature, battery charge status, etc., etc., and several actuators ² . The ECU ₂ computer is duly programmed to execute several engine control functions such as: idling control, regulation of the richness of the air / fuel mixture, adjustment of the ignition advance of this mixture and recirculation exhaust gases. To do this, the ECU ₂ computer uses information from the abovementioned sensors C ^z _± and develops control signals for the actuators ² j constituted by an additional air control valve and a spark plug ignition coil for the "regulation" function. idling ", a fuel injector for the" richness regulator "function, the same ignition coil for the" ignition advance "function and a valve for the" exhaust gas recirculation "function.

The other "services" mentioned above, "air conditioning of the passenger compartment", "connection with the ground", etc. are executed by systems of architecture similar to that presented above for controlling the engine.

In such a context, the list of digital signal frames is called "messaging" _. which, in a given vehicle, carry the data consumed or produced by each of the systems, this data being made available to _. other systems on the multiplex bus which interconnects them.

Currently the construction of such a messaging takes place mainly during the development phase of the vehicle. The computers of the various electronic systems are programmed to receive and transmit frames of predetermined signals.

When a vehicle is produced in several versions which differ in their equipment or in the services offered, the messaging services of the various

versions may also differ.

For each version, a basic messaging system is adapted, using calibration data stored in the computers of the various electronic systems of the vehicle.

This messaging generation process is however not very flexible, because it requires starting from a basic messaging, predefined in the vehicle development phase, and therefore of rigid structure, using a software tool such as VOLCANO, available from the Swedish company Volcano Communication Technologies AB.

In addition, different versions of the same vehicle are commonly released today, one behind the other, from the same production line. It would be desirable to be able to load each vehicle with personalized messaging that is adapted to it, for example just before it leaves the line. A software tool such as that mentioned above, suitable for the progressive construction of a messaging system during the development phase of the various versions of the vehicle, is not structured so as to allow the provision of such a service.

The present invention therefore aims to provide a device for generating a messaging common to several electronic systems producing and consuming data, designed to overcome the difficulties mentioned above and, in particular, to allow the loading of such a messaging in motor vehicles progressing on the same production line, messaging of each vehicle being personalized according to the services> and / or the equipment specific to each of these vehicles.

This object of the invention is achieved, as well as others which will appear on reading the description which follows, with a device for generating messaging common to several electronic systems producing and consuming data exchanged on a bus. multiplex communication interconnecting said systems, said data being carried by digital signal frames each comprising at least one of said data, this device being remarkable in that it comprises a) means for listing data potentially produced or consumed by said systems as well as the characteristics of said data, b) means for configuring the signal frames produced by each of the systems, these means comprising: bl) means for reading the content of said means for listing said data, b2) means for formatting formats said frames, on the basis of the information gathered by said reading and predetermined rules defining an architecture of said messaging conditioning the operation of the bus and said electronic systems, and c) loading means, in each. of said systems, frame formats developed by said means of constitution for the transmission of frames loaded with data produced by said system.

As will be seen below in detail, this device makes it possible to optimize the structure of the messaging loaded in each vehicle, while simplifying the development process of this messaging.

According to other characteristics of the present invention: the listing means are constituted by a plurality of interface means each associated with one of said electronic systems and listing the data potentially produced or consumed by said system, - each of the electronic systems comprises an electronic control unit, the interface means being constituted by electronic memories each associated with one of said electronic control units, said electronic memories store characteristics of said data chosen from the group formed by: the accuracy of the data, the frequency of its presentation on the bus, the identity of the control unit which produces the data, the identity of the control unit (s) which consume it, - the frame format constitution means proceed according to a heuristic method,

the device further comprises means for constituting the format of masks for the reading, by each of said systems, of the data which they consume and which are incorporated into frames produced by the other systems,

the electronic systems are on board a motor vehicle where they are interconnected in a CAN type communication bus, the means for configuring frames or masks being incorporated into a computer placed on the edge of a motor vehicle production line, wireless communication means being installed between this computer and the bus.

Other characteristics and advantages of the present invention will appear on reading the description which follows and on examining the appended drawing in which: FIG. 1 is a diagram of the messaging generation device according to the present invention, already shown partially described in the preamble to this description, FIG. 2 represents the format of a frame of digital signals representative of those generated by the device according to the invention,

FIG. 3 is a table, established by the device of FIG. 1, listing the data to be introduced into frames of digital signals formatted by this device, and

- Figures 4 and 5 are illustrative examples of tables, established by this device, listing the data contained in digital signal frames forming part of the messaging generated by the device according to the invention.

Referring to Figure 1 of the accompanying drawing where it appears that the ECU _α ... ECU _n , etc, ... computers electronic systems are each equipped with interface means Ii, ... I _n , etc. respectively , constituted by ROM memories, for example. In these memories are listed the data potentially emitted or produced and the data potentially consumed by the associated system, in two separate tables. For each of these data, the memory I _n associated with the calculator UCE _n lists the name of the data, its precision, or "size", in bits and the periodicity of the presentation of this data on the bus. Thus, for example, some data can be presented on the bus every 50 ms, others every 100 or 200 ms. This is the case with data which must be, in practice, constantly available such as, in an electronic management system of an internal combustion engine, the pressure at the intake manifold or the engine speed. Other data can only be sent on the bus when a particular "Event" occurs.

All the data produced or consumed by all of the systems Si, ... S _n , etc. are, according to the invention, put in frames of digital signals. AT As an illustrative and nonlimiting example only, FIG. 2 of the accompanying drawing shows the format of such a frame of such signals, of the well-known CAN type. A CAN frame thus comprises various fields, SOF field at the start of frame, EOF field at the end of frame, etc ... and, in particular, an identifier field and a data field which may contain several different data, recorded in distinct zones x, y, z, ... of this field, which has 8 bytes. Each frame brings together data produced by the same "node" of all the electronic systems of FIG. 1, that is to say by the same computer ECU _n .

To construct the sets of frames that each computer must transmit, the device according to the invention comprises means MC for configuring these frames.

According to an advantageous characteristic of this device, these means are constituted by a computer placed, in the "automobile" application described in the preamble to this description, at the edge of a motor vehicle production line, so as to be able to interact with each of the UCE _n computers on board the same vehicle, via bus B and bidirectional connection means (not shown), installed between the computer and this bus. Advantageously, these connection means are of the "wireless" type and operate on radio frequency or microwave, for example.

Thanks to this link, the means MC for configuring the frames, the whole of which constitutes the "messaging" to be generated, can read the. content of the interfaces I _n of the computers of a vehicle which will leave the production line, analyze this content and build a coherent set of frame formats containing the data, the frame formats associated with each of the UCE _n computers then being recorded in means F _n for loading these formats associated with the respective computers (see FIG. 1), at the same time as the software means making it possible to construct these frames, or to extract relevant data from the frames accessible on the bus.

It is understood that it is then possible to load, at the edge of the chain, different versions of the same vehicle which exit successively from this chain, with "personalized" messaging services, closely adapted to each version.

The problem posed by the diversity of functionalities which are incorporated into vehicles which come out in different versions of the same production line is thus best managed, while reducing the development work which would otherwise be necessary to process, upstream of the chain, the problem of installing the various messaging systems required by different vehicles.

As shown diagrammatically in FIG. 1, the means MC for configuring the device according to the invention essentially comprise means LI for reading the content of the interface means I _n and means MF for constituting frame formats and, as will be seen further on, mask formats. The means LI for reading interfaces are software means which, on the basis of the information contained in the set of interface means I _n associated with the computers UCE _n , make it possible to form a table such as that illustrated in FIG. 3, listing all the data a, b, c, etc ... produced or consumed by the various systems of the set diagrammed in Figure 1 and, for each data, its "precision" or size, in bits, its period presentation on bus B, the identity of the computer which produces it and that (s) of the computer (s) which consumes it. This is how the data item named b occupies, in the frame which carries it, 1 bit of the data field. It appears on bus B every 50 ms, this data b being produced by the ECU _X and consumed by the ECU ₂ . Similarly, the data item e, the size of which covers the 8 bytes (64 bits) of the data field of the same CAN frame, and which is produced and consumed by the ECU computer ₃ , only appears on the bus. the occurrence of a particular event (Event) attached to this data. The wireless link established between the on-board MC computer. chain and the various interfaces I _n uses a communication protocol suitable for such a link, for example the Bluetooth protocol described in the document entitled "Bluetooth specification vlOB" edited by Dan Sônnerstan of the Swedish company called Pyramid Communication AB.

The means MF for constituting frame formats are software means which, on the basis of the information gathered in the table of FIG. 3 by the interface reading means LI, and of rules which will be defined in the following of this description , define an architecture of the messaging system to be loaded in all of the electronic systems of FIG. 1, that is to say the formats of the various frames of data-carrying signals produced by the different "nodes" of this set, that is to say by the various ECU _n computers.

To do this, the software means MF firstly constitute lists of all the data transmitted by the same computer, then classify this data according to their period of presentation (or "production") on the bus B. Then, by a self-learning or heuristic method, the MF means ensure optimal grouping of data in frames, by the application of predetermined rules such as: each frame contains data produced by the same computer, the number of frames produced by the same computer is minimized, - the number of frames read by the same computer is minimized, the periods of presentation of the data of the same frame are identical or compatible, the lengths of the transmitted frames are balanced, as far as possible.

The purpose of these rules is to minimize the bus load, in particular the number of untimely interruption requests, triggered when a frame arrives on a computer consuming a data item contained in the frame.

The frame construction algorithm defined by the rules set out above can obviously be modified or supplemented by other possible rules, as necessary. It will be noted that certain frames constructed using this algorithm may be incomplete, in the sense that there remain in the data field of these frames unoccupied parts, which can therefore be occupied by future data. These must respect the production period of the reception frame and therefore present a period greater than or equal to that of the latter.

The tables of FIGS. 4 and 5 bring together the characteristics of two formats of frames representative of those of the sets of frames calculated by the means MC for configuring the device according to the invention, these frames being given by way of illustrative and nonlimiting example only. .

Each frame is named and each of the data carried by this. frame is identified by a coded number, on 16 bits for example, containing various fields identifying respectively the service of the vehicle in which the data participates, the function which uses the data and the name itself of the data. The frame defined by the table in FIG. 4 thus carries the data c and b from the table in FIG. 3. The data c is produced (P) by the calculator UCEi and consumed (C) by the calculator UCE ₂ . Its size is 1 bit, positioned at bit 7 of byte No. 1 (see Figure 2) of the data field of the frame. Data b has the same characteristics except that it is positioned at bit 6 of byte No. 1.

The frame defined by the table of FIG. 5 comprises only one data item f produced by the calculator UCE _α and consumed by the calculator UCE ₃ , its size is 64 bits, the most significant bit (MSB) being positioned at bit N ° 7 of byte N ° 1.

The frame formats established by the format constitution means MF correspond to frames whose priorities are, in the case of a CAN bus, determined by the content of the identifier field of these frames.

As an illustrative and nonlimiting example only, the allocation of priority to the various frames can be done in application of the so-called "Rate Monotony" criterion as described in the work by Klein, MH et al entitled "A Practitioner 's Handbook for Real-Time Analysis: Guide to Rate Monotonie Analysis for Real-Time Systems ", Boston, USA, MA; editor: Klu er Académie Publishers, 1993. for periodic frames, possibly with a correction made by the degree of criticality of the information conveyed by the frame. The frames sent following an event may have a higher priority than the others and will be hierarchical between them according to the declared criticality of the data and, possibly, according to a priority level classification by systems (engine control, air conditioning, cabin, etc.).

The various versions of messaging calculated by the computer MC at the edge of the chain can advantageously be stored therein. So when two vehicles of the same version appear successively in front of this computer, the computer does not have to rerun, for the second vehicle, the calculations already performed when the first was passed. The format creation means MF first calculate, as described above, the messaging formats to be established for a given vehicle. From these formats, they then calculate mask formats. These masks are used, by each of the ECU _n computers, to determine, among all the frames presented on the bus B, those which contain data which they use, then to locate on these frames the position or positions of these data in the data fields, in order to read the identified data. The frame formats and mask formats used by each ECU _n computer are stored in the loading means of formats F _n associated with this computer, these means being constituted by a read-only memory of the "E2PROM" type for example. Also stored in this memory are the software means making it possible to construct the frames and the masks, from data defining the formats thereof.

The device according to the invention then operates as follows. Different versions of the same vehicle progress successively on a production line at the edge of which the computer MC of this device is installed. When a vehicle arrives at the MC computer, it interrogates using the wireless communication means mentioned above, the various ECU computers _{n on} board the vehicle in order to recognize it. For this purpose, each of these computers is attached a predetermined identifier, recognized by the computer. Advantageously, this identifier further defines an order of priority in the systems associated with the identified computers.

Means can also be provided for securing communications between a vehicle and the computer, in order to prevent unwanted bus access (hacking, sabotage, etc.). To do this each computer may contain a code that is executed ^• After previously only the launch of frame configuration and masks. This code allows the computer to respond to requests from the configuration computer MC by giving its identity, then the list of data it must receive and then that of the data it must produce. The computer interrogates each computer in the order defined by the priority integrated into the identifier of this computer and configures the frames and masks associated with this computer as described above. Finally, it loads the calculated configurations and the software means for constructing frames and masks from these configurations, into the associated memory F _n . The MC computer also loads the alarms and events to be monitored into this memory.

By way of illustrative and nonlimiting example only is described below ^'in more detail one embodiment of means used to generate frames and to retrieve data therefrom. To do this, we define frame activation vectors, frame vectors and frame tables. For each frame and each data, the tables define the position of the data in the frame and the position of this same data in memory. Periodically, for example every 5 ms, the software means examine whether to send a frame. If necessary, they first of all update the frame vectors. If a data item must be sent immediately, the production of the data command sets an activation bit of the corresponding frame to "1" in the activation vector of the frames.

If the data is to be sent periodically by means of a periodic frame, the activation bit of this frame is set to 1, in the activation vector of the frames, with a corresponding frequency.

The activation vector of the frames is traversed periodically, for example every 5 ms, to start the procedure for sending all the frames for which the activation bit is at 1 in this activation vector of the frames.

The frame table allows you to find in memory the values of the data to be sent in the activated frames. Conversely, to receive data in frames, the procedure can be as follows. The arrival of the frame on the bus triggering an interrupt, this interrupt triggers a task, consisting in storing the frame in a buffer memory. After reading the identifier of this frame, contained in the identifier field of this one, and reading in the vector of frames of the beginning of the corresponding table of frames, the task takes in this one the data of the frame which are to read and then write to RAM memory, to refresh the data contained therein. The masks making it possible to select the frames which must be used by such or such central unit UCEi, are also developed by the messaging generation device according to the invention.

It now appears that the invention does indeed achieve the stated goals of ensuring the generation of personalized messaging for a set of electronic systems on board a motor vehicle, and loading of this messaging into this vehicle, from the edge of its production line, this in a particularly efficient and rational manner.

It will further be noted that the generation of messaging according to the present invention makes it possible to reduce the development time of this messaging. The proposed generation process can still be implemented without difficulty by progressive modifications of the current classic process, mainly occurring during the development phase.

Of course, the present invention is not limited to the embodiment described and shown, which has been given only by way of example. Thus the reading of the information on the exchanges of data stored in the interface means I _n could be replaced by the prior constitution of a database gathering this information, this, however, to the detriment of the flexibility of the device according to the invention.

It is thus also that the messaging generation device described above in the context of a set of electronic systems on board a motor vehicle, could easily adapt to any set of computers operating in a network, as will appear. immediately to the skilled person.

Claims

1. Device for generating messaging common to several electronic systems (S _n ) producing and consuming data (a, b, c, ...) exchanged on a multiplex communication bus (B) interconnecting said systems, said data (a, b, c, ...) being carried by digital signal frames each comprising at least one of said data, this device being characterized in that it comprises: a) means (I _n ) for listing the data likely to be produced or used by said systems as well as the characteristics of said data, b) means (MC) for configuring the signal frames produced by each of said systems, these means comprising: bl) reading means (LI) of the content of said means (I _n ) of listing said data, b2) of means (MF) of constituting the formats of said frames, from information gathered by said reading means (LI), and of predetermined rules defined ant an architecture of said messaging conditioning the operation of the bus and said electronic systems, and c) means (F _n ) for loading, into each of said systems (S _n ), of frame formats developed by said means (MC) of constitution for the transmission of frames loaded with data produced by said system.

2. Device according to claim 1, characterized in that said listing means are constituted by a plurality of interface means (I) each associated with one of said electronic systems (S _n ) and listing the data potentially produced or consumed by said system.

3. Device according to claim 2, characterized in that each of said systems electronics (S _n ) comprises an electronic control unit (UCE _n ), and in that said interface means (I _n ) are constituted by electronic memories each associated with one of said electronic control units (UCE _n ) .

4. Device according to claim 3, characterized in that said electronic memories (I _n ) store characteristics of said data chosen from the group formed by: the precision of the data, the frequency of its presentation on the bus (B), the identity of the control unit that produces the data, the identity of the control unit (s) that consume it.

5. Device according to claim 4, characterized in that said rules implemented by said means (MF) of constituting frame formats are chosen from the group formed by: a) each frame contains data produced by the same unit control unit (ECU _n ), b) the number of frames produced by or read by the same control unit is minimized, c) the frequency of presentation of the data contained in the same frame (T) is identical or compatible , d) the lengths of the frames are balanced.

6. Device according to claim 5, characterized in that said means (MF) for constituting frame formats proceed according to a heuristic method.

7. Device according to any one of claims 1 to β, characterized in that it comprises means for constituting mask formats for the reading, by each of said systems, of the data which it consumes and which are incorporated into frames produced by other systems.

8. Device according to any one of claims 3 to 7, characterized in that said frame or mask formats associated with any one (S _n ) of said electronic systems are loaded into an electronic memory (F _n ) associated with the control unit (UCE _n ) of said system (S _n ).

9. Device according to claim 8, characterized in that said memory (F _n ) is also loaded with software means for constructing frames or masks, from stored formats.

10. Device according to any one of claims 1 to 9, characterized in that said electronic systems are embedded in a motor vehicle.

11. Device according to claim 10, characterized in that the communication bus (B) is of the CAN type.

12. Device according to any one of claims 10 and 11, characterized in that said means (MF) of configuration of frames or masks are incorporated into a computer placed at the edge of a production line of motor vehicles each equipped of said plurality of electronic systems (S _n ) producing and consuming data exchanged on a multiplex bus (B).

13.- Device according to claim 12, characterized in that it comprises wireless communication means installed between said computer and said bus (B), said means being activated for the generation of said messaging.