@wizro_pl Ok, sorry now I understand. You can use any of the comparsion functions (taken from the help): GT > decreasing sequence, GE >= Monotonous decreasing sequence, EQ = Equality ,LE <= Monotonous increasing sequence, LT < Increasing sequence, NE <> Inequality
Writing your own function blocks is taken as a advanced function so the user actually know what is doing. But actually the only thing that is simple mode doing is that it automatically generates variable, which you can do also by right click on the device using the autogen.
Of course Mervis changes that. You have to choose which is the default access to the IOs. It is not a good idea to control output from two points without letting know each other about the change. But if you really want to, you can set the variable to be written only on change (right click on the device on the modbus channel and make custom).