Semantic Error (SEM1276): Reading values of generic formal parameters is not allowed.
In an assignment statement in ST, the value of a single generic FB formal parameter is to be written to a variable. Read access to generic formal parameters (ANY* data types) is not allowed this way.
Error example
Although the variable a is of the data type INT, and the input BUF_INT of the BUF_TO_BYTE function block is of ANY_INT, the following read access is invalid.
a := BUF_TO_BYTE1.BUF_CNT;
Remedy
Double-clicking the error message opens the code and marks the incorrect code position. Delete the assignment of the generic FB formal parameter to the variable.