Thanks for your response.
As one flexray node on a car, my ecu communicate with many other ecus.
I attached the flexray log below(NULLFRAME.png).
You can see that this frame is expeceted to transmit at slot 23, cycle (1,9,17,25...)
But at other cycles, it also transmit null frame.
Cycle filter function seems not work any more.
I am so confused about this...