Method for error diagnosis of can communication
In a method for error diagnosis of CAN communication, the rolling counter values stored in the main electronic and sub-electronic control devices are compared with each other. When a rolling counter difference value lies within the predetermined error diagnosis reservation range, the determination on the error diagnosis for the corresponding CAN communication is reserved. When the accumulated number of the error diagnoses reaches the predetermined number for the error diagnosis determination as the rolling counter difference value departs from the error diagnosis reservation range, an error is determined. When the rolling counter values of the main electronic and the sub-electronic control devices match each other, the error diagnosis for the CAN communication is normal, in which case, even if the temporary signal delay phenomenon (that is, the Jitter) occurs in the CAN communication, an erroneous diagnosis of the error for the CAN communication can be efficiently interrupted.
1. A method for an error diagnosis of CAN communication based on a rolling counter difference value between rolling counter values of a main electronic control device and a sub-electronic control device, the method comprising:
comparing rolling counter values of the main electronic control device and the sub-electronic control device in an error diagnosis device to arrive at a comparison result; and
determining continuation or reservation of an error diagnosis for a CAN message through determining whether or not the rolling counter difference value lies within a predetermined error diagnosis reservation range from the comparison result.
2. The method according to claim 1 , wherein the determining of the continuation or the reservation comprises reserving a determination of the error diagnosis for the CAN message when the rolling counter difference value lies within the predetermined error diagnosis reservation range.
3. The method according to claim 1 , further comprising:
increasing and accumulating a number of the error diagnoses when the rolling counter difference values departs from the predetermined error diagnosis reservation range; and
determining the continuation of the error diagnosis for the CAN message based on the accumulated number of the error diagnoses.
4. The method according to claim 3 , further comprising, when the accumulated number of the error diagnoses for the CAN communication is not higher than or equal to a predetermined number for an error diagnosis decision,
matching the rolling counter value of the main electronic control device with the rolling counter value of the sub-electronic control device, and
repeatedly executing the reservation of the error diagnosis in the error diagnosis device.
5. The method according to claim 3 , further comprising:
when the number of the error diagnoses for the CAN communication is higher than or equal to a predetermined number for an error diagnosis decision, determining an error occurrence for the CAN communication in the error diagnosis device.
6. The method according to claim 4 , further comprising:
matching the rolling counter value of the main electronic control device with the rolling counter value of the sub-electronic control device; or
updating a counterpart rolling counter value to any one of the rolling counter values of the main electronic control device and the sub-electronic control device, and matching the rolling counter values.