ST_FTR_IIRCoeff

Configuration structure for the function block FB_FTR_IIRCoeff.

Syntax

Definition:

TYPE ST_FTR_IIRCoeff :
STRUCT
    pCoefficientArrayAdr_A  : POINTER TO LREAL;
    nCoefficientArraySize_A : UDINT;
    pCoefficientArrayAdr_B  : POINTER TO LREAL;
    nCoefficientArraySize_B : UDINT;
    bReset                  : BOOL := TRUE;
    nOversamples            : UDINT;
    nChannels               : UDINT;
    pInitialValues          : POINTER TO LREAL;
    nInitialValuesSize      : UDINT;
END_STRUCT
END_TYPE

Parameter

Name

Type

Description

pCoefficientArrayAdr_A

Pointer to LREAL

Pointer to an array with filter coefficients ak (denominator)
[a0, a1, a2, …, aN]

nCoefficientArraySize_A

UDINT

Size of the array [a0, a1, a2, ..., aN] in BYTE

pCoefficientArrayAdr_B

Pointer to LREAL

Pointer to an array with filter coefficients bk (numerator)
[b0, b1, b2, …, bM]

nCoefficientArraySize_B

UDINT

Size of the array [b0, b1, b2, ..., bM] in BYTE

bReset

BOOL

If TRUE, a reset is performed when the filter is configured.
If FALSE, the historical values x[n-k] and y[n-k] are not reset.

nOversamples

UDINT

Number of oversamples (greater than zero)

nChannels

UDINT

Number of channels (greater than zero and less than 101)

pInitialValues

Pointer to LREAL

Pointer to array with initial values (optional)

nInitialValuesSize

UDINT

Size of the array with initial values in BYTE (optional)