The InOut interface in Siemens TIA Portal is a powerful tool for memory management and program efficiency. Instead of copying data in and out of blocks like traditional Inputs and Outputs, InOut passes variables by reference… using a pointer behind the scenes. This approach saves memory, reduces execution time, and keeps your programs lean.
You can easily recognise InOut parameters in TIA Portal by the double arrow symbol, which shows that data flows both into and back out of a Function or Function Block. While this can be incredibly efficient when working with large data structures, it’s important to understand the potential drawbacks, such as issues with cross-referencing and project-wide searches.
If you’re learning Siemens TIA Portal and want to understand how InOut interfaces work, when to use them, and what pitfalls to avoid, this guide will walk you through the key points.
