RU2176028C1 - Procedure of modification of data in permanent storage of unit controlling engine - Google Patents

Abstract

FIELD: engine manufacture. SUBSTANCE: invention can be used in unit controlling engine to detect illegal modification of data in permanent storage. Characteristic feature of invention lies in that message on legitimacy of conducted modification of data is entered in permanent storage when data are modified. In this case message on legitimacy of modification of data can include information on test sums of data put into sectors of permanent storage of unit controlling engine. This message can be encoded prior to recording in permanent storage. Objective of proposed procedure of modification of data in permanent storage of unit controlling automobile engine is formation of mechanism of early detection of illegal modification of data in permanent storage of control unit. EFFECT: early detection of illegal modification of data in permanent storage of control unit. 1 cl, 1 dwg

Description

 The invention relates to engine building and can be used in the engine control unit to detect illegitimate data changes in read-only memory (hereinafter - ROM) of the engine control unit.

 Known engine management systems, including sensors operating parameters, actuators and an engine control unit equipped with a microprocessor and read-only memory (hereinafter - ROM). The ROM of the control unit stores the data necessary to ensure the normal functioning of the engine.

 Modification of these data may lead, at least, to a violation of the established exhaust gas toxicity standards.

 Therefore, access to the data contained in the ROM of the engine control unit is usually password protected.

 For the prototype of the proposed method, the method of changing data in the ROM of the vehicle engine control unit described in PCT application N 89/05398, MKI4 F 02 D 43/00, 41/26, publ. 06/15/89, in which the control unit is connected to the computer, the password is entered from the keyboard, the correct password is entered in the control unit, if the password is correct, access to the data stored in the ROM is made, and changes are made to this data.

 The practice of operating VAZ automobiles shows that protecting access to the contents of the ROM of the password management unit is not sufficiently effective.

 During the period of operation of the car, in order to eliminate unreasonable claims of the car owner against its manufacturer, it is important to identify the fact of illegitimate changes in the contents of the ROM.

 The objective of the proposed method for changing data in the ROM of the vehicle engine control unit is to create a mechanism for early detection of illegitimate data changes in the ROM of the control unit.

 This problem is solved in a way of changing data in the ROM of the vehicle engine control unit, in which the control unit is connected to the computer, the password is entered from the computer keyboard, the correct password is entered in the control unit, if the password is correct, access to the data stored in the ROM is opened, and make changes to the above data.

 The problem is solved in that in the ROM when the data is changed, a message is written about the legitimacy of the data change. At the same time, the message about the legitimacy of the data change may contain information about the checksums of the data located in the ROM sectors of the engine control unit 1. The message before writing to the ROM can be encrypted.

 The invention is illustrated by the following drawing, which shows a diagram of a car engine control system. The method can be implemented programmatically in a car engine control system (see drawing), which includes an engine control unit 1 equipped with a processor 2, ROM 3 and an interface 4 for connecting a computer, a computer 5 equipped with a keyboard 6, and a lamp 7 for fault monitoring .

 To implement the method perform the following steps.

 1. Enter the password from the keyboard 6.

 2. Check in block 1 of the engine control the correctness of the entered password.

 3. With a correctly entered password, computer 5 is opened access to ROM 3 of engine control unit 1.

 4. Change the data in the ROM.

 5. Compose a message about the legitimacy of data changes in the ROM.

 6. If necessary, encrypt the message in the established manner.

 7. Enter from the keyboard 6 of computer 5 in ROM 3 a message about the legitimacy of changing the data stored in the ROM.

 For early identification and simplification of the procedure for detecting illegitimate data changes in ROM 3 when the engine is started, the engine control unit 1 checks whether the information on the data provided in the data change legitimacy message is stored in the ROM cells. The encrypted message is previously decrypted by the control unit 1 in an established manner.

 If a discrepancy is found in the information given in the message about the legitimacy of changing the data in ROM 1 to the data contained in the ROM cells, they conclude that there is an illegitimate interference in the ROM 3 of the engine control unit 1, a malfunction code is generated in the engine control unit 1, and it is transmitted by turning on the lamp 7 control of faults included in the engine management system.

 The inventive method allows the manufacturer to promptly identify the fact of an illegitimate change in the contents of the ROM and to exclude unreasonable claims by the car owner on the quality of the engine management system.

Claims (3)

 1. The method of changing data in the ROM of the vehicle engine control unit, in which the control unit is connected to the computer, the password is entered from the computer keyboard, the correct password is entered in the control unit, if the password is correct, access to the data stored in the ROM is opened, and changes are made in the mentioned data, characterized in that in the ROM when the data is changed, a message is written about the legitimacy of the data change.  2. The method according to claim 1, characterized in that the message about the legitimacy of the data change contains information about the checksums of the data located in the ROM sectors of the engine control unit 1.  3. The method according to claims 1 and 2, characterized in that the message about the legitimacy of data changes before being written to the ROM is encrypted.