Apparatus for a controller area network

A Controller Area Network (CAN) transceiver comprising processing circuitry configured to:

• receive transmit-data (TX data), the TX data generated by a CAN controller to cause the CAN transceiver to transmit CAN signals that encode the TX data on the CAN bus;
• and
• receive CAN signals encoding receive-data (RX data) via the CAN bus;
• detect, in the RX data, one or more fields of a CAN frame;
• and
• prevent the CAN transceiver from transmitting the TX data on the CAN bus at times corresponding to the one or more fields of the CAN frame detected in the RX data;
• wherein preventing the CAN transceiver from transmitting the TX data on the CAN bus at the times corresponding to the one or more fields of the CAN frame detected in the RX data prevents an error frame in the TX data from being transmitted on the CAN bus;
• wherein the processing circuitry is configured to store a security level parameter in memory coupled to the processing circuitry;
• wherein a number of the one or more fields of the CAN frame detected in the RX data is a first number of fields when the security level parameter has a first value;
• and
• wherein a number of the one or more fields of the CAN frame detected in the RX data is a second number larger that than first number when the security level parameter has a second value.