CODEWITHSUNDEEP
autosarautomotive
Thanh Nguyễn
Thanh Nguyễn

Reputation: 1

ECU waked up by the Can error frame (Automotive)

I am encountering a issue that is ECU waked up by error frame. Then, I got report from the testing team for this issue. I am wondering why error frame can wake up the ECU in sleep mode? how can?

who know this issue or encountered this one, Please help me

I really appreciate your willing to support!

Upvotes: 0

Views: 772

Answers (2)

Xuân Tâm
Xuân Tâm

Reputation: 166

I am not sure about your Hardware Design but there is nothing wrong with "wakeup" in this case. Usually decision wakeup made by CAN Controller which is not a part of Micro Controller (MCU). It always wakeup if it detect Wakeup Pattern (check Can controller datasheet) and then it will trigger some HW PIN INH , RX/TX to MCU. That time MCU need to wakeup fast enough to check what is first CAN message.. at this point you only know what is CAN Frame. So the expectation if CAN Frame Error MCU will not wakeup is also wrong.. How do you know if it is a Error Frame.. if you not wakeup yet. Correct expectation is what ECU will do after that.. ECU should first check if it is valid CAN Frame and Valid wakeup reason to be awake or not.. Otherwise it should be put to sleep again. Please also check NetworkManageMent Specification from Autosar for more information.

Upvotes: 0

kesselhaus
kesselhaus

Reputation: 1496

Wake-Up Pattern in CAN / CAN FD Networks

So, a wakeup pattern is like dominant for >5µs .. with 500kB/s CAN, bit time is 2µs/bit, this is like 2.5 bits.

Active Error Frame is defined as "six dominant bits transmitted by ECU detecting failure" .. I would say, that would be plenty of time for a >5µs wakeup pattern

Upvotes: 1

Related Questions