Tutorial_02: How to create Function Block (FB) In Codesys V2.3 Using Structured Text .
This Video Demonstates How to work with user defined Function Block (FB) In Codesys V2.3 Using Structured Text .
Watch Tutorial_01: https://bit.ly/3cAFPm1
to know better about Program Logic and it's Visualisation
You Can use codesys free software to Program WAGO PLC and many other.