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BIQUAD

NAME
SYNOPSIS
DESCRIPTION
FUNCTIONS
PINS
PARAMETERS
LICENSE

NAME

biquad − Biquad IIR filter

SYNOPSIS

loadrt biquad [count=N]

DESCRIPTION

Biquad IIR filter. Implements the following transfer function: H(z) = (n0 + n1z-1 + n2z-2) / (1+ d1z-1 + d2z-2)

FUNCTIONS

biquad.N (uses floating-point)

PINS

biquad.N.in float in

Filter input.

biquad.N.out float out

Filter output.

biquad.N.enable bit in (default: 0)

Filter enable. When false, the in is passed to out without any filtering. A transition from false to true causes filter coefficients to be calculated according to parameters

biquad.N.valid bit out (default: 0)

When false, indicates an error occured when caclulating filter coefficients.

PARAMETERS

biquad.N.type u32 rw (default: 0)

Filter type determines the type of filter coefficients calculated. When 0, coefficients must be loaded directly. When 1, a low pass filter is created. When 2, a notch filter is created.

biquad.N.f0 float rw (default: 250.0)

The corner frequency of the filter.

biquad.N.Q float rw (default: 0.7071)

The Q of the filter.

biquad.N.d1 float rw (default: 0.0)

1st-delayed denominator coef

biquad.N.d2 float rw (default: 0.0)

2nd-delayed denominator coef

biquad.N.n0 float rw (default: 1.0)

non-delayed numerator coef

biquad.N.n1 float rw (default: 0.0)

1st-delayed numerator coef

biquad.N.n2 float rw (default: 0.0)

2nd-delayed numerator coef

biquad.N.s1 float rw (default: 0.0)

biquad.N.s2 float rw (default: 0.0)

LICENSE

GPL