JP2000089822A - Electronic control system for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electronic control system for vehicle capable of standardizing a connector and reducing the cost without the need of increasing the terminal number of the connector for diagnosis even in the case of additionally installing an ECU. SOLUTION: The rewrite control means of all electronic control units is operated by a rewrite command transmitted from a rewrite command means through the connector (step S12), an identification code from the rewrite command means and the identification code intrinsic to a storage means are collated (step S14) and the storage contents of the storage means are rewritten in the case that they match (step S15). Thus, the need of allocating the terminal of the connector for every electronic control unit like the case of selectively operating the electronic control unit requiring rewrite is eliminated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle electronic control system having a plurality of electronic control units (hereinafter, referred to as ECUs) for controlling a vehicle engine, an automatic transmission, and the like. The present invention relates to a technique for selectively rewriting a control program stored in a storage unit.

[0002]

2. Related Art As is well known, this kind of vehicle electronic control system is an EEPROM (Electrical Erasable &
An engine, an automatic transmission, and the like are controlled based on a control program stored in a Programmable ROM) and the like. When the content of the control program is changed, for example,
As described in JP-A-6-299852, a portable failure diagnosis tester is connected via a connector, and a program is rewritten by a command from the failure diagnosis tester.

However, the above publication is based on an electronic control system having a single ECU, and for example, a plurality of ECs for individually controlling engine control and shift control.
In the electronic control system with U, the program rewriting E
It is necessary to add a function for selecting a CU. Therefore, for example, in the electronic control system B including the engine ECU 21 and the automatic transmission ECU 22 shown in FIG. 4, the start-up signal VPP is transmitted from the failure diagnosis tester 6 to select the ECUs 21 and 22 that need to rewrite the program. It is configured to be able to. Specifically, each of the ECUs 21 and
Reference numeral 22 is connected to a diagnosis connector 25 via a common communication line 23 used for program rewriting and the like and a separate start command line 24 for a start signal VPP. As shown in FIG. 5, a communication line 23 includes an EEPROM 26 storing a control program and a ROM 27 storing a boot program for rewriting a control program.
And these EEPROM 26 and ROM 27
Is selectively connected to the CPU 28. The CPU 28 is normally switched to the EEPROM 26 to execute engine control and transmission control based on the control program. When the start signal VPP is applied from the start command line 24, the CPU 28 is switched to the ROM 27. ing.

When rewriting the control program of any one of the ECUs 21 and 22 of the electronic control system B configured as described above, first, a failure diagnosis for the failure is made to the connector 25 of the electronic control system B via the interface cartridge 6a. The tester 6 is connected, and a request such as a part number or a program ID is transmitted from the failure diagnosis tester 6 to each of the ECUs 21 and 22 via the communication line 23. Each ECU 21,
When the failure diagnosis tester 6 confirms that the vehicle type is the target vehicle type based on the information returned from 22, the failure diagnosis tester 6 selects the activation command line 24 of the ECUs 21 and 22 that require program rewriting, and transmits the activation signal VPP. In response to the start signal VPP, in the target ECUs 21 and 22, the CPU 28
27, the boot program is started, and a new control program is transferred from the failure diagnosis tester 6 via the communication line 23.
The control program in the EEPROM 26 is rewritten by the PU 28.

[0005]

However, in the conventional vehicle electronic control system B, the start signals VPP are transmitted only to the ECUs 21 and 22 that need to rewrite the program. A command line 24 is required. In recent years, the control target of this type of system has been rapidly expanding, and not only the engine and the automatic transmission but also, for example, a brake and a suspension are being electronically controlled. Therefore, the required number of the start command lines 24 increases with the addition of the ECUs 21 and 22. As a result, the number of terminals of the diagnosis connector 25 needs to be increased, and the number of units in the control system B differs. In this case, the number of terminals of the connector 25 is different, so that the connector 25 cannot be standardized, resulting in an increase in cost.

[0006] Further, with the change of the connector 25, the failure diagnosis tester 6 also needs to change the hardware specifications (specifically, the specification change of the interface cartridge 6a). Since the diagnostic tester 6 is provided for each vehicle dealer (dealer), enormous costs are required to take countermeasures for all of them.

An object of the present invention is to eliminate the need for increasing the number of terminals of a diagnosis connector even when an ECU is added, to reduce the cost by standardizing the connector, and to reduce the hardware on the failure tester side. It is an object of the present invention to provide an electronic control system for a vehicle which does not require a change in specifications of the vehicle and can respond at a low cost.

[0008]

In order to achieve the above object, according to the present invention, a connector is commonly connected to a plurality of electronic control units whose storage contents can be rewritten by built-in rewriting control means. It operates according to a rewrite command transmitted from the rewrite command means via the connector, compares the identification code from the rewrite command means with the unique identification code stored in the storage means, and stores a match in the storage means if the two match. The rewriting control means is configured to rewrite the contents. In other words, the rewriting control means of all the electronic control units are operated to identify the electronic control unit requiring the rewriting of the stored content by collating the identification code, so that the rewriting control means of the electronic control unit requiring the rewriting can be selectively performed. There is no need to assign connector terminals for each electronic control unit to operate. Also, the rewriting command means can be realized by a software change for transmitting the identification code.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a vehicle electronic control system embodying the present invention will be described below. As shown in FIG. 1, the electronic control system A of the present embodiment includes an engine E
CU1, ECU2 for automatic transmission, and ABS (anti-
ECU 3 for skid / brake system), and each of ECUs 1 to 3 has a detachable failure diagnosis tester 6 as rewriting command means via a common communication line 4 and a common start command line 5. It is connected to a gnosis connector 7. As shown in FIG. 2, the communication line 4 is connected to a rewritable EEPROM 8 and a non-rewritable ROM 9 as storage means in each of the ECUs 1 to 3.

The EEPROM 8 of each of the ECUs 1 to 3 stores a control program for operating and diagnosing an engine, an automatic transmission, or an ABS to be controlled, and a unique identification code 10 in advance. Is stored. The ROM 9 has a rewrite of the control program and an identification code 10 read from the control program.
Are stored.

The EEPROM 8 and the ROM 9 are provided with a CPU 11 so as to be selectively connectable.
Is switched to the EEPROM 8 to execute control of an object to be controlled (engine, automatic transmission, ABS) or the like based on a control program.
When VPP is applied, the mode is switched to the ROM 9 side to start the boot program. In this embodiment, the rewriting control means is constituted by the ROM 9 storing the control program and the CPU 11.

Next, the procedure for rewriting the control programs of the predetermined ECUs 1 to 3 in the vehicle electronic control system A configured as described above will be described with reference to the flowchart of FIG. The processing on the failure diagnosis tester 6 side is as follows.
C (not shown) built in based on operator's button operation
Executed by PU. First, the failure diagnosis tester 6 is connected to the connector 7 of the electronic control system A via the interface cartridge 6a.
A request such as a part number or a program ID is transmitted to the CUs 1 to 3 via the communication line 4 (step S1). In response to the request from the failure diagnosis tester 6, the ECUs 1 to 3 return information such as their own part numbers and program IDs (step S11). It is checked whether the ECU is an ECU (step S
2). If it is not the target ECU, that is, if the type of the engine, the automatic transmission, the ABS, etc. is different and it is estimated that it is not the target vehicle type, the subsequent processing is terminated.

If the ECU is the target ECU, the failure diagnosis tester 6 transmits a start signal VPP via the start command line 5 (step S3). As described above, in the present embodiment, since the start command line 5 is shared among the ECUs 1 to 3, the start signal VPP is input to all the ECUs 1 to 3, and the CPU 11 is switched to the ROM 9 to execute the boot program. Is started (step S12). Next, the failure diagnostic tester 6 transmits the identification code 10 of the control program requiring rewriting to each of the ECUs 1 to 3 via the communication line 4 (step S4), and the CPU 11 executes the identification code stored in each EEPROM 8 in accordance with the boot program. The code 10 is read out (step S13) and collated with the received identification code 10 (step S14). The CPU 11 whose identification code 10 does not match interrupts the processing until the application of the activation signal VPP is completed, and the CPU 11 whose identification code 10 matches matches continues the processing.

Next, the failure diagnosis tester 6 transfers a new control program via the communication line 4 (step S).
5) The control program executes the CP
The control program is rewritten and checked according to the boot program by being received only by the U (CPU with the matching identification code 10) 11 (step S15). Thereafter, the failure diagnosis tester 6 terminates the transmission of the activation signal VPP (step S6), and in response to this, in each of the ECUs 1 to 3, switching from the EEPROM 8 to the ROM 9 is performed to activate the control program and rewrite the program. The process ends (step S16).

As described above, in the vehicle electronic control system A of this embodiment, when the control program is rewritten, the boot programs of all the ECUs 1 to 3 are activated, and the program rewriting is required by collating the identification code 10. ECU
Since the numbers 1 to 3 are identified, it is only necessary to provide a single start command line 5 regardless of the number of ECUs 1 to 3 installed. Therefore, the ECUs 21 and 22 needing program rewriting
It is no longer necessary to provide a start command line 24 for each of the ECUs 21 and 22 and to assign the terminals of the diagnosis connector 25 as in the conventional example in which only the boot program is selectively started. Can be reduced.

Further, when changing from the conventional example to the vehicle electronic control system A of this embodiment, the identification code 10 is stored in the EEPROM 8 and the collation processing of the identification code 10 is performed in the boot program of the ROM 9 (step S1).
4) is added, and all of them are software changes, so that they can be handled very easily. Further, since the ROM 9 can be shared among the ECUs 1 to 3, the manufacturing cost can be further reduced. it can.

On the other hand, the failure diagnosis tester 6 also
Since it can be realized by a software change only by adding the transmission process of the identification code 10 (step S4), it is possible to cope with a very low cost as compared with a hardware specification change as in the conventional example. This concludes the description of the embodiment, but aspects of the present invention are not limited to this embodiment. For example, in the above-described embodiment, the ECUs 1 to 3 are mainly provided for each control (engine, automatic transmission, ABS) necessary for running the vehicle.
And the control program in each of the ECUs 1 to 3 was rewritten. However, the content of the control program is not limited to the one for traveling, and for example, the air conditioning control
When a U or a navigation ECU is added, the control program may be rewritten. In the above embodiment, the control program is rewritten by the failure diagnosis tester 6 having a program rewriting function, but a dedicated program rewriting device may be used.

[0018]

As described above, according to the electronic control system for a vehicle according to the present invention, the electronic control unit requiring rewriting of the stored content is identified by collation of the identification code, so that the terminal of the connector is provided for each electronic control unit. It is not necessary to assign a connector, and the connector can be standardized to reduce the manufacturing cost. In addition, since the failure diagnosis tester can be realized by a software change for transmitting the identification code, it can be handled at a very low cost as compared with a hardware specification change.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram showing a vehicle electronic control system according to an embodiment when a failure diagnosis tester is connected.

FIG. 2 is a configuration diagram showing a connection state between each line and an ECU.

FIG. 3 is a flowchart illustrating a procedure at the time of rewriting a control program.

FIG. 4 is an overall configuration diagram showing a conventional vehicle electronic control system when a failure diagnosis tester is connected.

FIG. 5 is a configuration diagram showing a connection state between each line and an ECU.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Engine ECU (Electronic Control Unit) 2 Automatic Transmission ECU (Electronic Control Unit) 3 ABS ECU (Electronic Control Unit) 6 Fault Diagnosis Tester (Rewrite Instruction Means) 7 Connector 8 EEPROM (Storage Means) 9 ROM ( Rewriting control means) 10 Identification code 11 CPU (Rewriting control means)

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Yoshiki Ohno 5-33-8 Shiba, Minato-ku, Tokyo Inside Mitsubishi Motors Corporation (72) Inventor Shinichi Kuraya 5-33-8 Shiba, Minato-ku, Tokyo Mitsubishi Motors Corporation (72) Inventor Noriko Hayase 5-33-8 Shiba, Minato-ku, Tokyo Mitsubishi Motors Corporation (72) Inventor Jiro Sumiya 2-3-2 Marunouchi, Chiyoda-ku, Tokyo Mitsubishi Inside Electric Co., Ltd. (72) Inventor Kazunori Mori 6-12-2 Hamayama-dori, Hyogo-ku, Kobe-shi, Hyogo Mitsubishi Electric Control Software Co., Ltd. (72) Inventor Mitsuru Hayakawa 6-1-1, Hamayama-dori, Hyogo-ku, Kobe-shi, Hyogo No. 2 Mitsubishi Electric Control Software Co., Ltd. F-term (reference) 5H223 AA10 CC08 DD03 EE15 EE19

Claims (1)

[Claims] A plurality of electronic control units each having a built-in rewritable storage means and a rewrite control means for controlling rewriting of storage contents of the storage means; And a connector to which the means is attached and detached. The rewriting control means of each of the electronic control units is operated by a rewriting command transmitted from the rewriting command means connected to the connector, and the identification transmitted from the rewriting command means. An electronic control system for a vehicle, wherein a code is compared with a unique identification code stored in said storage means, and when both codes match, the storage content of said storage means is rewritten.