template class xf::dsp::aie::fir::interpolate_fract_asym::fir_interpolate_fract_asym_graph

#include "fir_interpolate_fract_asym_graph.hpp"

Overview

fir_interpolate_fract_asym is an Asymmetric Fractional Interpolation FIR filter

These are the templates to configure the Asymmetric Fractional Interpolation FIR class.

Parameters:

TT_DATA describes the type of individual data samples input to and output from the filter function. This is a typename and must be one of the following: int16, cint16, int32, cint32, float, cfloat.
TT_COEFF

describes the type of individual coefficients of the filter taps. It must be one of the same set of types listed for TT_DATA and must also satisfy the following rules:

  • Complex types are only supported when TT_DATA is also complex.
  • 32 bit types are only supported when TT_DATA is also a 32 bit type,
  • TT_COEFF must be an integer type if TT_DATA is an integer type
  • TT_COEFF must be a float type if TT_DATA is a float type.
TP_FIR_LEN is an unsigned integer which describes the number of taps in the filter.
TP_INTERPOLATE_FACTOR is an unsigned integer which describes the interpolation factor of the filter. TP_INTERPOLATE_FACTOR must be in the range 3 to 16.
TP_DECIMATE_FACTOR is an unsigned integer which describes the decimation factor of the filter. TP_DECIMATE_FACTOR must be in the range 2 to 16. The decimation factor should be less that the interpolation factor and should not be divisible factor of the interpolation factor.
TP_SHIFT is describes power of 2 shift down applied to the accumulation of FIR terms before output. TP_SHIFT must be in the range 0 to 61.
TP_RND describes the selection of rounding to be applied during the shift down stage of processing. TP_RND must be in the range 0 to 7 where 0 = floor (truncate) eg. 3.8 Would become 3. 1 = ceiling e.g. 3.2 would become 4. 2 = round to positive infinity. 3 = round to negative infinity. 4 = round symmetrical to infinity. 5 = round symmetrical to zero. 6 = round convergent to even. 7 = round convergent to odd. Modes 2 to 7 round to the nearest integer. They differ only in how they round for values of 0.5.
TP_INPUT_WINDOW_VSIZE describes the number of samples in the window API used for input to the filter function. The number of values in the output window will be TP_INPUT_WINDOW_VSIZE multipled by TP_INTERPOLATE_FACTOR and divided by TP_DECIMATE_FACTOR. In the instance this would lead to a fraction number of output samples, this would be rounded down. Note: Margin size should not be included in TP_INPUT_WINDOW_VSIZE.
TP_CASC_LEN describes the number of AIE processors to split the operation over. This allows resource to be traded for higher performance. TP_CASC_LEN must be in the range 1 (default) to 9.
TP_USE_COEFF_RELOAD selects if runtime coefficient reloading is used. 0 = Runtime coefficient reloading is not used. Coefficients are passes into the graph constructor and cannot be changed during runtime. 1 = Runtime coefficient reloading is used. Coefficients are not passed into the graph constructor and are set using the graph API update function.
template <
    typename TT_DATA,
    typename TT_COEFF,
    unsigned int TP_FIR_LEN,
    unsigned int TP_INTERPOLATE_FACTOR,
    unsigned int TP_DECIMATE_FACTOR,
    unsigned int TP_SHIFT,
    unsigned int TP_RND,
    unsigned int TP_INPUT_WINDOW_VSIZE,
    unsigned int TP_CASC_LEN = 1,
    unsigned int TP_USE_COEFF_RELOAD = 0,
    unsigned int TP_NUM_OUTPUTS = 1
    >
class fir_interpolate_fract_asym_graph: public graph

// fields

port <input> in
port <output> out

Fields

port <input> in

The input data to the function. This input is a window API of samples of TT_DATA type. The number of samples in the window is described by TP_INPUT_WINDOW_VSIZE. Note: Margin is added internally to the graph, when connecting input port with kernel port. Therefore, margin should not be added when connecting graph to a higher level design unit. Margin size (in Bytes) equals to TP_FIR_LEN rounded up to a nearest multiple of 32 bytes.

port <output> out

A window API of TP_INPUT_WINDOW_VSIZE*TP_INTERPOLATE_FACTOR/TP_DECIMATE_FACTOR samples of TT_DATA type.

Methods

getKernels

kernel* getKernels ()

Access function to get pointer to kernel (or first kernel in a chained configuration).

fir_interpolate_fract_asym_graph

fir_interpolate_fract_asym_graph (const std::vector <TT_COEFF>& taps)

This is the constructor function for the asymmetrical decimator FIR graph with static coefficients.

Parameters:

taps
  • a pointer to the array of taps values of type TT_COEFF.