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Arrays (TwinCAT PLC Control: User Data Types)
https://infosys.beckhoff.com/index.php?content=../content/1031/tcplccontrol/html/TcPlcCtrl_ARRAY.htm&id=
arr1 : ARRAY[1..3] OF STRUCT1:= [(p1:=1,p2:=10,p3:=4723), (p1:=2,p2:=0,p3:=299), (p1:=14,p2:=5,p3:=112)];