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• MUX

MUX

Type	Function
Description	Forwards the value connected to input INn to the output if the selection input K = n.
Notes	When the string output is longer than 80 characters and the FU/FB is directly connected to another FU/FB, temporary string variables of size 80 are used. Calculation/usage will fail. Use an intermediate local variable in-between. Overloaded function. The function can operate on various input data types. Further inputs can be added. The function provides implicit data type conversion at its INn inputs and the output according to the rules defined by the IEC 61131 standard.
Parameters	Inputs K Data type: ANY_ELEMENTARY Description: Selection value. IN0 Data type: ANY_ELEMENTARY Description: Input value. IN1 Data type: ANY_ELEMENTARY Description: Input value. Output OUT Data type: ANY Description: Output value.
Error behavior	Error behavior The following table shows the errors which may occur while executing the function and the value returned by the function in the corresponding error case. Error case Output value Value connected to K outside the scope IN0 IN = NaN Note: ENO stays true in the error case. NaN IN = Inf+ Note: ENO stays true in the error case. Inf+ IN = Inf- Note: ENO stays true in the error case. Inf- Resulted string too short Empty string Note String comparison: In case of a string error, the function returns the empty string ''. Furthermore, the controller runtime logs the error in its error catalog and a corresponding error message is shown in the Error List. Note Controller stop on string error: The controller can be automatically stopped when a string error occurs. This allows you to locate the error in your project. To enable the automatic stop of the controller in case of a string error, activate the button in the Cockpit toolbar of the controller.
Additional information	EN/ENO behavior The POU is only executed if TRUE is applied to the EN input. If EN = FALSE, the POU is not executed and ENO = FALSE indicates the inactivity. ENO is set to FALSE if the value connected to the input K is outside the scope of the data type (see "Error behavior" above). Invalid real values are passed to the output without setting ENO to FALSE because the function does not interpret values. Further Info See the topic "General information on execution control with EN/ENO" for further details.