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Iām trying to implement message prioritization on the CAN Bus for my Smart Industrial Monitoring System. High-priority messages (emergency alerts) should be transmitted before regular sensor data. Iām using the AVR128DA48 with Zephyr OS. This is how Iāve set up the message:
“`
struct zcan_frame emergency_frame = {
.id_type = CAN_STANDARD_IDENTIFIER,
.rtr = CAN_DATAFRAME,
.id = 0x100, // Higher priority
.dlc = 1,
.data = {0xFF},
};
struct zcan_frame regular_frame = {
.id_type = CAN_STANDARD_IDENTIFIER,
.rtr = CAN_DATAFRAME,
.id = 0x300, // Lower priority
.dlc = 1,
.data = {0x01},
};
“`
Both messages are being transmitted, but Iām noticing that the regular messages are sometimes sent before the emergency ones. What am I missing in terms of message prioritization on the CAN Bus, and how can I ensure that high-priority messages are always transmitted first?
it would help it you understood how CAN arbitration works
@destynin CAN Bus prioritization is based on the identifier of the message. The lower the identifier value, the higher the priority. If your high-priority messages are not being sent first, check your identifier values if they are correct, your message transmission queue and hardware/software configuration
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