摘要:
A vehicle security system with an anti-theft controller which conducts a data exchange with at least one function controller, particularly an engine controller, in order to control its operational readiness, wherein the data exchange is conducted via a data line connecting at least the anti-theft controller and the function controller. Alternatively, an external device (4) can be connected to the data line (1), with the device being configured for the exchange of data with at least one of the controllers (2, 3, 3', 3") The data line is a line which is already in existence in the vehicle, particularly a K-diagnostics line and/or an L-diagnostics line in accordance with ISO standard 9141. For the control of the data exchange, one of the controllers (2, 3) connected via the data line (1) exercises the functions of the control unit. If an external device (4) is connected to the data line (1, 1'), the external device assumes the function of the control unit from the controller (2, 3) controlling the data exchange in order to conduct the data exchange with the controllers (2, 3, 3', 3") connected via the data line (1).
摘要:
A method of operating a microcomputer system in which at least part of a memory system of the microcomputer system is checked for manipulation of data stored in the memory system. Measures to prevent processing of the data in the microcomputer system are performed as a function of the result of the check, if the measures are activated. The measures are activated or deactivated as a function of the content of a read-only memory of the microcomputer system. To increase the effectiveness and reliability of a manipulation or tuning protection of the data, a code word is stored in the data, which is checked while the microcomputer system is in operation, and the measures are activated or deactivated as a function of the result of the check of the code word stored in the data.
摘要:
A method of protecting a microcomputer system against manipulation of data stored in a memory assembly of the microcomputer system is provided. The method may protect, for example, a control program stored in the memory assembly of a motor vehicle control device. To secure and reliably protect the microcomputer system against manipulation of the data, the data is stored in the memory assembly marked or encrypted using an asymmetrical encryption method. The data may, for example, be encrypted outside the microcomputer system using an encryption algorithm and a private key, which is accessible to only a limited group of persons. The data may be decrypted in the microcomputer system using a decryption algorithm and a freely accessible public key.
摘要:
The process for serially transmitting information entities over a serial bus between subscribers (ECU1 to ECU4) at a common transmission rate for all subscribers, includes providing the information entities with a start bit (Sta) at a beginning of transmission of each of the information entities; waiting to transmit the information entities on the bus from each subscriber until after a bus monitoring time period (T.sub.U) assigned to each subscriber has elapsed; setting a flag after a subscriber receives one of the information entities; monitoring a logic state of the serial bus during a bus monitoring time period (T.sub.U) at a monitoring rate sufficiently high so that receipt of each information entity is detected during reception of a start bit (Sta); each subscriber determining the state of the flag after expiration of the bus monitoring period (T.sub.U); and only then transmitting the information entities from the subscriber if the subscriber does not detect that the flag is set during the bus monitoring time period (T.sub.U).