Hello Diep_TrinhXuan
thanks for your information, I have a problem when using master flag, I want to make RollingCounter add 1 when receive master flag, so code is below

keep mater node send msg, I power off the slave node, then I power on the slave node, the RollingCounter sent by slave have the following problem in the first/second frame
the correct RollingCounter shall be 0, 1, 2, 3,4, not 0, 0, 1, 2, 3

I guess it is a sequential problem, slave node have respond the msg after receiving master msg before application detect the flag is 1, so it's late to write the RollingCounter signal to the data buffer.
so do you have any suggestions?