A method of detecting errors in data transmission within a CAN controller and a CAN controller for carrying out this method

A method of detecting errors in data transmission within a CAN controller (13, 20), particularly in the data transmission between a microprocessor (14, 21) and an interface unit (23), for over a CAN bus (11, 22) data to be transmitted by the microprocessor (14, 21) at least one check bit is generated, which can be checked to ensure the consistency of the transmitted data, characterized, in that the check bit generated the interface unit (23) indicates whether safety data are available, wherein the interface unit (23) checks said at least one check bit with security-relevant data.