FB_CTRL_MEDIAN_FILTER

The function block specifies the median. The median is the mean value of a list of values ordered by size. This means that one half of the collected data values is smaller than the median value, the other half is larger.

The programmer must create an array "ARRAY [1..2(n+2)] OF LREAL", in which the function block can store the internal required data.

Inputs

VAR_INPUT
    fIn                 : FLOAT;
    fManSyncValue       : FLOAT;
    eMode               : E_CTRL_MODE;    
    bSync               : FLOAT;
    bHold               : BOOL;
END_VAR

Name	Type	Description
fIn	FLOAT	Input value of the median filter
fManSyncValue	FLOAT	Input value to which the median filter can be set or which is output in manual mode.
eMode	E_CTRL_MODE	With a rising edge at this input the median filter is set to the value "fManSyncValue".
bSync	FLOAT	Input that specifies the operation mode of the function block.
bHold	BOOL	TRUE at this input holds the internal state and thus also the output.

Outputs

VAR_OUTPUT
    fOut        : FLOAT;
    eState      : E_CTRL_STATE;
    eErrorId    : E_CTRL_ERRORCODES;
    bError      : BOOL;
END_VAR

Name	Type	Description
fOut	FLOAT	Output of the median filter
eState	E_CTRL_STATE	Status of the function block
eErrorId	E_CTRL_ERRORCODES	Supplies the error number when the output `bError` is set.
bError	BOOL	Becomes TRUE, as soon as an error occurs.

Inputs/ outputs

VAR_IN_OUT
    tCtrlCycleTime        : TIME := T#0ms;
    tTaskCycleTime        : TIME := T#0ms;
    nSamplesToFilter      : UINT;
    pWorkArray_ADR        : POINTER TO FLOAT := 0;
    nWorkArray_SIZEOF     : UINT := 0;
END_VAR

Name	Type	Description
tCtrlCycleTime	TIME	Cycle time with which the control loop is processed. This must be greater than or equal to the TaskCycleTime. The function block uses this input value to calculate internally whether the state and the output values have to be updated in the current cycle.
tTaskCycleTime	TIME	Cycle time with which the function block is called. If the function block is called in every cycle this corresponds to the task cycle time of the calling task.
nSamplesTo Filter	UINT	Number of values "n" used to form the median value.
pWorkArray_ ADR	POINTER TO FLOAT	The address of the array where the input values are temporarily stored.
nWorkArray_ SIZEOF	UINT	Size of the `WorkArrays`