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The CAN protocol supports a variety of baud rates, including 250bps, 500bps, and 1Mbps. These baud rates are usually selected based on factors such as the transmission distance of the CAN bus network and the noisy environment.
In general, a lower baud rate can provide a longer transmission distance and better anti-interference ability, but it will also reduce the data transmission speed. The higher baud rate can improve the data transmission speed, but may reduce the transmission distance and anti-interference ability.
In practical applications, the appropriate baud rate is usually selected according to the specific needs and network environment. For example, in automotive control systems, lower baud rates are usually chosen to ensure longer transmission distances and better anti-interference capabilities; In some high-speed application scenarios, a higher baud rate may be selected to improve the data transmission speed. CAN bus adopts asynchronous serial communication, that is, there is no separate clock line to ensure the consistency of the clock between each transceiver, each transceiver is according to the pre-set baud rate to the level on the bus. Therefore, the accurate baud rate setting is very important for the stable communication of CAN bus.
In CAN bus, we CAN realize the communication of different baud rates by controlling the bit timing register in CAN node. The CAN protocol divides a bit time into synchronization segment, propagation segment, phase buffer segment 1 and phase buffer segment 2. The time length of each segment can be expressed as a base time unit of an integer, which is obtained by frequency division of the system's clock oscillator.
The synchronization segment is located at the starting position of a bit, and CAN-bus stipulates that the jump edge is the synchronization signal. However, there is a network propagation delay between the sending node sending a bit and the receiving node receiving this bit, and the propagation segment is to compensate for this propagation delay. Since the sampling point is located between phase buffer segment 1 and phase buffer segment 2, By setting the values of phase buffer segment 1 and phase buffer segment 2, the position of the sampling points can be adjusted to ensure that each bit sampling point is consistent. The length adjustment range of the buffer segment is determined by the synchronous jump width (SJW).
The CAN protocol supports a variety of baud rates, including 250bps, 500bps, and 1Mbps. These baud rates are usually selected based on factors such as the transmission distance of the CAN bus network and the noisy environment.
In general, a lower baud rate can provide a longer transmission distance and better anti-interference ability, but it will also reduce the data transmission speed. The higher baud rate can improve the data transmission speed, but may reduce the transmission distance and anti-interference ability.
In practical applications, the appropriate baud rate is usually selected according to the specific needs and network environment. For example, in automotive control systems, lower baud rates are usually chosen to ensure longer transmission distances and better anti-interference capabilities; In some high-speed application scenarios, a higher baud rate may be selected to improve the data transmission speed. CAN bus adopts asynchronous serial communication, that is, there is no separate clock line to ensure the consistency of the clock between each transceiver, each transceiver is according to the pre-set baud rate to the level on the bus. Therefore, the accurate baud rate setting is very important for the stable communication of CAN bus.
In CAN bus, we CAN realize the communication of different baud rates by controlling the bit timing register in CAN node. The CAN protocol divides a bit time into synchronization segment, propagation segment, phase buffer segment 1 and phase buffer segment 2. The time length of each segment can be expressed as a base time unit of an integer, which is obtained by frequency division of the system's clock oscillator.
The synchronization segment is located at the starting position of a bit, and CAN-bus stipulates that the jump edge is the synchronization signal. However, there is a network propagation delay between the sending node sending a bit and the receiving node receiving this bit, and the propagation segment is to compensate for this propagation delay. Since the sampling point is located between phase buffer segment 1 and phase buffer segment 2, By setting the values of phase buffer segment 1 and phase buffer segment 2, the position of the sampling points can be adjusted to ensure that each bit sampling point is consistent. The length adjustment range of the buffer segment is determined by the synchronous jump width (SJW).
