Can communication method and data frame structure for improving communication speed through increase in data amount
A controller area network (CAN) communication method for electronic devices of a vehicle includes: transmitting data using a data frame in which communication mode information designating high speed CAN communication processing or general CAN communication processing is inserted into a null bit or a reserved bit that is not used in a general CAN communication protocol; receiving the transmitted data; and processing the received data in a high speed CAN communication mode or a general CAN communication mode based on the communication mode information.
1. A controller area network (CAN) communication method for electronic devices of a vehicle, comprising:
transmitting data using a data frame in which communication mode information designating high speed CAN communication processing or general CAN communication processing is inserted into a null bit or a reserved bit;
receiving the transmitted data; and
processing the received data in a high speed CAN communication mode or a general CAN communication mode based on the communication mode information,
wherein the data frame includes:
a remote transmission request (RTR) bit for designating whether a communication mode is the general CAN communication mode or the high speed CAN communication mode, and
an extend data length (EDL) bit for designating whether a data length is 8 bytes or less or 8 bytes or more.
2. The CAN communication method according to claim 1 , wherein the processing of the received data includes processing data of 8 bytes or less carried in a data field of the data frame at a communication speed of 1 Mbps or less when the received data is processed using the general CAN communication mode.
3. The CAN communication method according to claim 1 , wherein the processing of the received data includes processing data of 8 bytes or less carried in a data field of the data frame at a communication speed of 1 Mbps or less or 2 Mbps or more, depending on communication speed information included in the communication mode information, when a data length is 8 bytes or less and the received data is processed using the high speed CAN communication mode.
4. The CAN communication method according to claim 1 , wherein the processing of the received data includes processing data of 8 bytes or more carried in a data field of the data frame at a communication speed of 1 Mbps or less or 2 Mbps or more, depending on communication speed information included in the communication mode information, when a data length is 8 bytes or more and the received data is processed using the high speed CAN communication mode.
5. The CAN communication method according to claim 1 , wherein the data frame further includes:
a bit rate switch (BRS) bit for designating whether a communication speed is 1 Mbps or less or 2 Mbps or more.
6. The CAN communication method according to claim 5 , wherein the RTR bit is allocated to the null bit of the data frame.
7. The CAN communication method according to claim 5 , wherein the EDL bit and the BRS bit are allocated to the reserved bit included in a control field of the data frame.
8. The CAN communication method according to claim 1 , wherein the data frame further includes one bit for designating whether a communication speed is less than or more than a predetermined number of Mbps.