How to Wakeup from Sleep during CAN network state transition?

Question

I am trying to understand the CAN network management of AUTOSAR. I am trying to sleep the ECU if there are no CAN message received during IGN cycle. I am blocking the CAN transmission and reception during this stage. Now suppose AUTOSAR NM message is received, i want to make the ECU to wakeup and need to make CAN to be full active. I have gone through the basic Autosar Network management understanding.

As per my understanding

If communication on the bus is needed i.e. requested, NM messages are sent out. If no communication is needed i.e. released, sending of NM messages is stopped.

When the Autosar NM state is "Ready Sleep state" or "Repeat Message State", I am waking up the CAN. I would like to know, this is a good approach.

Answer 1

Reference: AUTOSAR_SWS_CANNetworkManagement.pdf

You need to read detail the state diagram in section 7.20 for the state and possible transition.

The wake-up and sleep in network management means the communication state. And the specification defines the state to synchronize between ECUs in vehicle. For examples:

• During bus-sleep state is state that you disable the CAN controller and CAN transceiver.
• During wake-up, you will initiate the communication state again for full communication.

Note: Beware about the state of sending/receiving the NM message because it is sync signal for all ECUs.