Capsim Block Documentation
This star produces the fft of the input signal. The points are output as complex numbers.
Port | Type | Name | |
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0 | complex | x |
Port | Type | Name | |
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0 | complex | y |
Num | Description | Type | Name | Default Value | |
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0 | Size of FFT | int | npts | 128 |
Num | Type | Name | Initial Value | Description |
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0 | int | fftexp | ||
1 | int | fftl | ||
2 | cap_fft_cpx* | cxinBuff | ||
3 | cap_fft_cpx* | cxoutBuff | ||
4 | cap_fft_cfg | cfg | ||
5 | int | pointCount | 0 |
int no_samples; complex calc; int i,j; |
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fftl=npts; fprintf(stderr,"cmxfft: fft length is: %d \n", fftl); if (fftl < 2) { fprintf(stderr,"cmxfft: fft length is too short \n"); return(1); } cfg=cap_fft_alloc(fftl,0,NULL,NULL); if ((cxinBuff = (cap_fft_cpx*)calloc(fftl,sizeof(cap_fft_cpx))) == NULL) { fprintf(stderr,"cmxfft: can't allocate work space \n"); return(2); } if ((cxoutBuff = (cap_fft_cpx*)calloc(fftl,sizeof(cap_fft_cpx))) == NULL) { fprintf(stderr,"cmxfft: can't allocate work space \n"); return(3); } SET_CELL_SIZE_IN(0,sizeof(complex)); SET_CELL_SIZE_OUT(0,sizeof(complex)); |
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for (no_samples = MIN_AVAIL(); no_samples > 0; --no_samples) { /* * real input buffer */ j=pointCount; IT_IN(0); cxinBuff[j].r=x(0).re; cxinBuff[j].i=x(0).im; pointCount++; /* * Get enough points */ if(pointCount >= fftl ) { /* * perform fft calculation */ cap_fft(cfg, cxinBuff, cxoutBuff); /* * now, output complex pairs */ for (i=0; i |
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/* * free up allocated space */ free((cap_fft_cpx*)cxinBuff); free((cap_fft_cpx*)cxoutBuff); |
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/* Capsim (r) Text Mode Kernel (TMK) Star Library (Blocks) Copyright (C) 1989-2017 Silicon DSP Corporation This library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with this library; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA http://www.silicondsp.com Silicon DSP Corporation Las Vegas, Nevada */ |
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/* cmxfft.s */ /*********************************************************************** cmxfft() ************************************************************************ Inputs: x complex Outputs: y, the fft of the signal complex Parameters: int inpts the fft length ************************************************************************ This star produces the fft of the input signal. The points are output as complex numbers. The number of points input is npts and the number of points generated is npts; Programmer: Prayson Pate Date: April 15, 1988 Modified: April 18, 1988 Modified: Sasan Ardalan to use cxfft() routine, use complex buffers. */ |
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