Best way for read and write?

Hello
I'm working on project with labview .
with this program i connecting PC to the MCU through sreial RTU modbus .
in this program there are some data need to be read and some data need to write .
what i need is most of my time reading polet exuted exept when some of control element (like edit box) has changed by user .
when ever some thing changed by user write polet excuted .
now what is the best way to do this ?
Best Regards.
Solved!
Go to Solution.

mori64 wrote:
What uou said sound complicated to me .
i'm trying to undrestand your solution .
i'll be happy if you upload sample program .
State Machine
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