Beckhoff EPP3504-0023 Short Manual page 105

Commissioning
nDecimationValue :LREAL := 50/44.1; // 50/20;
nOVS :BYTE := 5; // Oversampling factor
nTaskCycle_ns :UDINT := 500000; // PlcTask configured cycle time in ns
nOVSTimeInterval_ns :UDINT := LREAL_TO_UDINT(nTaskCycle_ns/nOVS); // OVS interval
nDecTimeInterval_ns :LREAL := nDecimationValue * nOVSTimeInterval_ns; // Decimation interval
END_VAR
VAR
aSamples_1 AT%I* :ARRAY[0..nOVS-1] OF DINT; // Link to the terminal PDO
aOVS_SampleSets :ARRAY[0..(2*nOVS)-1] OF DINT; // 2 OVS sample sets
nVarDecResult :DINT; // The calculated interpolated value
tVarDecResult :LREAL; // Decimation timestamp
aVarDecResult :ARRAY[0..nOVS-1] OF DINT; // Decimation result values
aVarDecResult_TS :ARRAY[0..nOVS-1] OF LREAL; // Decimation result timestamps
nResultNoOfSamples :BYTE; // This is for the user for further processing
nDivVar :INT; // Value for selection of the target input element
tDecVar_InTaskCycle :LREAL:=0; // Time span for all decimation timestamps within a task cycle
i :BYTE:=0; // Common loop counter
nDX :LREAL; // X-Difference: target input element to decimation element
nDY :DINT; // Y-Difference: two values for interpolation
sVal :LREAL; // Slope for calculation of new value
bEnable :BOOL:=FALSE; // Start/Stop conversion to decimation values
nOVS_CycleCount :ULINT := 0; // Time value for every OVS sample
// Values for testing
bTEST_VALUES_ENABLED :BOOL := FALSE; // No input value needed, if TRUE
nPhi :LREAL := 1.4; // Start angle for sinus simulation
// For visualization only:
aOVS_Samples :ARRAY[0..nOVS-1] OF DINT; // 2 OVS sample sets (value)
aOVS_Samples_TS :ARRAY[0..nOVS-1] OF ULINT; // 2 OVS sample sets (timestamp)
END_VAR
Program
// 500 µs Task
FOR i:= 0 TO nOVS-1 DO
// Shift OVS set to left and update on right:
aOVS_SampleSets[i] := aOVS_SampleSets[i+nOVS]; // Transfer "samples set" to the left side
IF bTEST_VALUES_ENABLED THEN
// Simulate values:
aOVS_SampleSets[i+nOVS] := LREAL_TO_DINT(1000000 * SIN(nPhi));
nPhi := nPhi + 0.01;//0.003141592653;
ELSE
// Fill current new samples set on right:
aOVS_SampleSets[i+nOVS] := aSamples_1[i];
END_IF
END_FOR
IF bEnable THEN
nResultNoOfSamples := 0; // Use for further processing
EPP3504-0023 Version: 1.2 105