Need help FFT !

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Hi,
I'm working on a FFT on the Xmc1302-T038x0200 from infinéon.
I use DAVE version 4.4.2.
I got all the headers and the main program from infinéon site.
There is my main program :


/* ----------------------------------------------------------------------
q* Copyright (C) 2010-2012 ARM Limited. All rights reserved.
*
* $Date: 17. January 2013
* $Revision: V1.4.0
*
* Project: CMSIS DSP Library
* Title: arm_fft_bin_example_f32.c
*
* Description: Example code demonstrating calculation of Max energy bin of
* frequency domain of input signal.
*
* Target Processor: Cortex-M4/Cortex-M3
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* - Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* - Neither the name of ARM LIMITED nor the names of its contributors
* may be used to endorse or promote products derived from this
* software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
* -------------------------------------------------------------------- */

/**
* @ingroup groupExamples
*/

/**
* @defgroup FrequencyBin Frequency Bin Example
*
* \par Description
* \par
* Demonstrates the calculation of the maximum energy bin in the frequency
* domain of the input signal with the use of Complex FFT, Complex
* Magnitude, and Maximum functions.
*
* \par Algorithm:
* \par
* The input test signal contains a 10 kHz signal with uniformly distributed white noise.
* Calculating the FFT of the input signal will give us the maximum energy of the
* bin corresponding to the input frequency of 10 kHz.
*
* \par Block Diagram:
* \image html FFTBin.gif "Block Diagram"
* \par
* The figure below shows the time domain signal of 10 kHz signal with
* uniformly distributed white noise, and the next figure shows the input
* in the frequency domain. The bin with maximum energy corresponds to 10 kHz signal.
* \par
* \image html FFTBinInput.gif "Input signal in Time domain"
* \image html FFTBinOutput.gif "Input signal in Frequency domain"
*
* \par Variables Description:
* \par
* \li \c testInput_f32_10khz points to the input data
* \li \c testOutput points to the output data
* \li \c fftSize length of FFT
* \li \c ifftFlag flag for the selection of CFFT/CIFFT
* \li \c doBitReverse Flag for selection of normal order or bit reversed order
* \li \c refIndex reference index value at which maximum energy of bin ocuurs
* \li \c testIndex calculated index value at which maximum energy of bin ocuurs
*
* \par CMSIS DSP Software Library Functions Used:
* \par
* - arm_cfft_f32()
* - arm_cmplx_mag_f32()
* - arm_max_f32()
*
* Refer
* \link arm_fft_bin_example_f32.c \endlink
*
*/


/** \example arm_fft_bin_example_f32.c
*/

#include "cmsis_dsp.h"
#include "arm_common_tables.h"
#include "stdio.h"
#include "DAVE.h"
#include "arm_math.h"
#include "arm_const_structs.h"
#include "arm_cfft_f32.h"
#include "arm_fft_bin_data.h"
#include "arm_complx_mag_f32.h"
#include "arm_max_f32.h"

uint32_t length=2048 ;

/* -------------------------------------------------------------------
* External Input and Output buffer Declarations for FFT Bin Example
* ------------------------------------------------------------------- */
extern float32_t testInput_f32_10khz[2048];
static float32_t testOutput[2048/2];

/*------------------------------------------------------------------
* Global variables for FFT Bin Example*/

/* ------------------------------------------------------------------- */
uint32_t fftSize = 1024;
uint8_t ifftFlag = 0;
uint32_t doBitReverse = 1;

/* Reference index at which max energy of bin ocuurs */
int refIndex = 213, testIndex = 0;

/* ----------------------------------------------------------------------
* Max magnitude FFT Bin test
* ------------------------------------------------------------------- */

int main(void)
{

float32_t maxValue;
arm_status status;
status = ARM_MATH_SUCCESS;
int arm_cfft_sR_f32_len2048=2048;



/* Process the data through the CFFT/CIFFT module */
arm_cfft_f32(&arm_cfft_sR_f32_len2048, testInput_f32_10khz, ifftFlag, doBitReverse);

/* Process the data through the Complex Magnitude Module for
calculating the magnitude at each bin */
arm_cmplx_mag_f32(testInput_f32_10khz, testOutput, fftSize);

/* Calculates maxValue and returns corresponding BIN value */
arm_max_f32(testOutput, fftSize, &maxValue, &testIndex);

if (testIndex != refIndex)
{
status = ARM_MATH_TEST_FAILURE;

}

/* ----------------------------------------------------------------------
** Loop here if the signals fail the PASS check.
** This denotes a test failure
** ------------------------------------------------------------------- */

if ( status != ARM_MATH_SUCCESS)
{
while (1);



}


while(1);/* main function does not return */;


}



/** \endlink */




I got a list of 3 warning :
3138.attach

Also there is 3 info for the function contains in headers :
3139.attach


When i use the debugger, i observe that there is anormal things for the following lines :

3140.attach



He is not affecting the great value for p2 and seems to not give any value to p3 and p4.

I hope that i gave you all the necessary information to help me resolve my problem.


Regards,

Charles
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