How can warm start a method in TwinCAT?

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One of the features of the method based on the definition of Beckoff site is that:

All data of a method are temporary and are only valid while the method is executed (stack variables). This means that TwinCAT re-initializes all variables and function blocks, which you have declared in a method, with each call of the method.

Is there any way to use a method in the plc loop as warm start!

it means that we use the method without re_initializing and method declare variations run just once at the first time we call it and the rest of the time that is called the variables retain their own values?

1 Answers

Yes, this is possible through VAR_INST or VAR_STAT. Just declare your variables as VAR_INST/VAR_STAT instead, then they will retain their values between the calls.

VAR_INST means it will be unique for every instantiation of the function block of where the method resides, while VAR_STAT will act as a static/global (all instances will point to the same memory location).

https://infosys.beckhoff.com/english.php?content=../content/1033/tc3_plc_intro/2528798091.html&id=

https://infosys.beckhoff.com/english.php?content=../content/1033/tc3_plc_intro/2528787339.html&id=

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