Build and flash the application, then open a serial terminal at 115200 baud and request a sample:
uart:~$ att_dummy sample
Requesting dummy sample...
[00:00:43.080,932] <inf> dummy_module: Dummy sample response: 1
uart:~$ att_dummy sample
Requesting dummy sample...
[00:05:40.587,219] <inf> dummy_module: Dummy sample response: 2
uart:~$
Each invocation publishes a DUMMY_SAMPLE_REQUEST to dummy_chan. The module's state machine handles it, increments its internal counter, and publishes a DUMMY_SAMPLE_RESPONSE. The shell's listener prints the counter value, confirming the round trip works end to end.
You can extend this dummy module by adding new message types, state variables, and processing logic to fit your specific use case.