METHOD AND DEVICE FOR TESTING THE CORRECT FUNCTION OF A SERIAL DATA TRANSMISSION

摘要

The invention relates to a method for checking the correct function of a serial data transmission in a bus system having at least two bus subscribers. The bus subscribers are connected to the bus by means of a bus connection unit and exchange messages via the bus. The sending access to the bus for each message is assigned to a bus subscriber by means of the arbitration method as per CAN standard ISO 11898-1, which bus subscriber becomes the sender for the particular message. The messages have a logical structure as per the CAN standard, in other words consist of a start-of-frame bit, arbitration field, control field, data field, CRC field, acknowledge field, and end-of-frame field. The correct function of the data transmission is checked during the transmission by comparing a sent signal sent to the bus connection unit with the received signal (CAN_RX) received by the bus connection unit. The method is characterized in that a sent signal (CAN_TX_DEL) delayed by a delay time (T_DELAY) compared to the sent signal (CAN_TX) is held in the sender, and the undelayed sent signal (CAN_TX) or the delayed sent signal (CAN_TX_DEL) is used for the check of the correct function of the data transmission depending on a switchover.