Solution:

To run initial commands only once. Add a tag 'Init' as a boolean type tag. Open a Math sheet. Expression : not Init Tag Expression ... ... ... ... Init 1 after Init set to "1", this Math will not execute. But you should be aware that : 1. When Studio is opened, all the variable value will set to "0", except tags initial value have already set in "tag property". 2. If you click Stop/Run, all variable value will keep last value.