CAN bus: Difference between revisions
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===Error States=== | ===Error States=== | ||
Each ECU maintains an RX Error counter and TX Error Counter (REC/TEC), initialized to 0. Successful operations reduce the appropriate counter by 1, though never below 0. Errors increase the counters (usually TEC by 8, | Each ECU maintains an RX Error counter and TX Error Counter (REC/TEC), initialized to 0. Successful operations reduce the appropriate counter by 1, though never below 0. Errors increase the counters (usually TEC by 8, REC by 1). Depending on the values of these counters, each ECU is in one of three error states: | ||
* Error-Active: Both counters are less than 128. The ECU will respond to errors with an Active Error Frame. | * Error-Active: Both counters are less than 128. The ECU will respond to errors with an Active Error Frame. | ||
* Error-Passive: One or both counters are greater than 127. The ECU will respond to errors with (network-transparent) Passive Error Frames. | * Error-Passive: One or both counters are greater than 127. The ECU will respond to errors with (network-transparent) Passive Error Frames. | ||