FlexRay CycleCounter Init value at MPC5674F

[cjw-442]

Hi, I m using MPC5674F for Flexray application.

I want to know the cycle counter when the core starts Flexray communication after being normal active.

I expected that cycle counter is 0 for all nodes within flexray network. But it was not 0 and different.

Thank you.

[Lyn]

I also set the cycle counter filter related registers. But it seems not work. At non-assigned cycle, the frame transmit as a null frame. Do you have this problems?(I use MPC5748G)

[PetrS]

Hi,

yes, it could be nonzero as bus setup must be done before node switch to normal active, as shown in Fig. 37 of AN12233; https://www.nxp.com/docs/en/application-note/AN12233.pdf

BR, Petr 

[cjw-442]

Thank you for quick Reply, Petr.

Our Flexray Parameters are as follows.

  - Communication Cycle is 500 us / 5 ms.

  - 2 Nodes are in Flexray Cluster (3 nodes will be joined later)

  - 3 Static slots (Using Key slot) / Only Dynamic Slots are using for Data Exchange.

I have three questions here.

  1. Do all nodes coupled to Flexray communication use the same Cycle Counter?

  2. If 1 is correct, how will Flexray communication be affected if the Cycle Counter between nodes is different?

  3. When node 1 sends data to Cycle 10, Slot 1, when does node 2 actually receive data?
Is it Cycle 10 or 11?

Thank you

[PetrS]

Hi,

per my understanding,
1. yes
2. communication will not work
3. in cycle 10

BR, Petr