int32_t splot_buff_2(void)
{
arm_status status; /* Status of the example */
arm_cfft_radix4_instance_f32 cfft_instance; /* CFFT Structure instance */
/* CFFT Structure instance pointer */
arm_cfft_radix4_instance_f32 *cfft_instance_ptr =
(arm_cfft_radix4_instance_f32*) &cfft_instance;
/* Initialise the fft input buffers with all zeros */
arm_fill_f32(0.0, buff_wej_dodatkowy_1, ile_probek);
arm_fill_f32(0.0, buff_wej_dodatkowy_2, ile_probek);
/* Copy the input values to the fft input buffers */
arm_copy_f32(ADC3ConvertedValue1, buff_wej_dodatkowy_1, ile_probek);
arm_copy_f32(buff_odp_imp_filtr, buff_wej_dodatkowy_2, ile_probek);
/* Initialize the CFFT function to compute 64 point fft */
status = arm_cfft_radix4_init_f32(cfft_instance_ptr, 64, 0, 1);
/* Transform input a[n] from time domain to frequency domain A[k] */
arm_cfft_radix4_f32(cfft_instance_ptr, buff_wej_dodatkowy_1);
/* Transform input b[n] from time domain to frequency domain B[k] */
arm_cfft_radix4_f32(cfft_instance_ptr, buff_wej_dodatkowy_2);
/* Complex Multiplication of the two input buffers in frequency domain */
arm_cmplx_mult_cmplx_f32(buff_wej_dodatkowy_1, buff_wej_dodatkowy_2, buff_wyj1, ile_probek);
/* Initialize the CIFFT function to compute 64 point ifft */
status = arm_cfft_radix4_init_f32(cfft_instance_ptr, 64, 1, 1);
/* Transform the multiplication output from frequency domain to time domain,
that gives the convolved output */
arm_cfft_radix4_f32(cfft_instance_ptr, buff_wyj1);
status = ARM_MATH_SUCCESS;
}
int32_t main(void)
{
arm_status status; /* Status of the example */
arm_cfft_radix4_instance_f32 cfft_instance; /* CFFT Structure instance */
/* CFFT Structure instance pointer */
arm_cfft_radix4_instance_f32 *cfft_instance_ptr =
(arm_cfft_radix4_instance_f32*) &cfft_instance;
/* output length of convolution */
outLen = srcALen + srcBLen - 1;
/* Initialise the fft input buffers with all zeros */
arm_fill_f32(0.0, Ak, MAX_BLOCKSIZE);
arm_fill_f32(0.0, Bk, MAX_BLOCKSIZE);
/* Copy the input values to the fft input buffers */
arm_copy_f32(testInputA_f32, Ak, MAX_BLOCKSIZE/2);
arm_copy_f32(testInputB_f32, Bk, MAX_BLOCKSIZE/2);
/* Initialize the CFFT function to compute 64 point fft */
status = arm_cfft_radix4_init_f32(cfft_instance_ptr, 64, 0, 1);
/* Transform input a[n] from time domain to frequency domain A[k] */
arm_cfft_radix4_f32(cfft_instance_ptr, Ak);
/* Transform input b[n] from time domain to frequency domain B[k] */
arm_cfft_radix4_f32(cfft_instance_ptr, Bk);
/* Complex Multiplication of the two input buffers in frequency domain */
arm_cmplx_mult_cmplx_f32(Ak, Bk, AxB, MAX_BLOCKSIZE/2);
/* Initialize the CIFFT function to compute 64 point ifft */
status = arm_cfft_radix4_init_f32(cfft_instance_ptr, 64, 1, 1);
/* Transform the multiplication output from frequency domain to time domain,
that gives the convolved output */
arm_cfft_radix4_f32(cfft_instance_ptr, AxB);
/* SNR Calculation */
snr = arm_snr_f32((float32_t *)testRefOutput_f32, AxB, srcALen + srcBLen - 1);
/* Compare the SNR with threshold to test whether the
computed output is matched with the reference output values. */
if( snr > SNR_THRESHOLD)
{
status = ARM_MATH_SUCCESS;
}
if( status != ARM_MATH_SUCCESS)
{
while(1);
}
while(1); /* main function does not return */
}
void fft(){
uint32_t i;
arm_cfft_radix4_instance_f32 S; /* ARM CFFT module */
float32_t maxValue; /* Max FFT value is stored here */
uint32_t maxIndex; /* Index in Output array where max value is */
uint32_t height;
for(i = 0; i < SIZE; i+=2)
{
INPUT[i] = ((samples[i]+CAP_FACTOR)/((float32_t) MAX_VALUE/2) - 1);
INPUT[i+1] = 0;
}
/* Initialize the CFFT/CIFFT module, intFlag = 0, doBitReverse = 1 */
arm_cfft_radix4_init_f32(&S, SIZE/2, 0, 1);
/* Process the data through the CFFT/CIFFT module */
arm_cfft_radix4_f32(&S, INPUT);
/* Process the data through the Complex Magniture Module for calculating the magnitude at each bin */
arm_cmplx_mag_f32(INPUT, Output, SIZE/2);
/* Calculates maxValue and returns corresponding value */
arm_max_f32(Output, SIZE, &maxValue, &maxIndex);
if(maxIndex>SIZE/4){
maxIndex=SIZE/2-maxIndex; //Dla lustrzanych
}
BSP_LCD_Clear(LCD_COLOR_WHITE);
/* Display data on LCD */
for (i = 0; i < SIZE; i++) {
/* Draw FFT results */
height = (uint16_t)(((float32_t)Output[i] / (float32_t)maxValue) * 180);
BSP_LCD_DrawLine(0, 30+i, height, 30+i);
}
char str[16];
sprintf(str,"%d",(uint32_t)((float32_t)maxIndex*FREQ_FACTOR)); //Model matematyczny
BSP_LCD_DisplayStringAtLine(1,(uint8_t *) str);
}
void fft_gen(void){
//TODO:バッファをstaticにして関数切り出し．割り込みから呼ぶ，切り出し先はfft.c
arm_cfft_radix4_instance_f32 S; /* ARM CFFT module */
float32_t Input[FFT_SAMPLES];
uint32_t maxIndex; /* Index in Output array where max value is */
//ジェネレータのバッファを埋める(ジェネレータ入力時の不足データを繰り返しで埋める)(TODO:ADとgenを振り分け)
uint16_t i;
int j;
j = 0;
for (i=buf.numLUTEntries; i < FFT_SIZE; i++)
{
buf.LUT_BUFFER[i] = buf.LUT_BUFFER[j];
if(j==buf.numLUTEntries-1)
{
j=0;
}else{
j++;
}
}
/* Initialize the CFFT/CIFFT module, intFlag = 0, doBitReverse = 1 */
arm_cfft_radix4_init_f32(&S, FFT_SIZE, 0, 1);
for (i = 0; i < FFT_SAMPLES; i += 2) {
Input[(uint16_t)i] = (float32_t)((float32_t)buf.LUT_BUFFER[i/2] - (float32_t)2048.0) / (float32_t)2048.0;
Input[(uint16_t)(i + 1)] = 0;
}
/* Process the data through the CFFT/CIFFT module */
arm_cfft_radix4_f32(&S, Input);
/* Process the data through the Complex Magniture Module for calculating the magnitude at each bin */
arm_cmplx_mag_f32(Input, Output, FFT_SIZE);
/* Calculates maxValue and returns corresponding value */
arm_max_f32(Output, FFT_SIZE, &maxValue, &maxIndex);
//DA=30000sps/4096bit=7.32421875Hzステップでデータが格納されている
}
int32_t main(void)
{
volatile int32_t iCount;
arm_status status;
arm_cfft_radix4_instance_f32 S;
float32_t maxValue;
STM_EVAL_LEDInit(LED3);
STM_EVAL_LEDInit(LED6);
STM_EVAL_LEDOff(LED3);
STM_EVAL_LEDOff(LED6);
status = ARM_MATH_SUCCESS;
/* Initialize the CFFT/CIFFT module */
status = arm_cfft_radix4_init_f32(&S, fftSize, ifftFlag, doBitReverse);
/* Process the data through the CFFT/CIFFT module */
arm_cfft_radix4_f32(&S, testInput_f32_10khz);
/* 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;
STM_EVAL_LEDOn(LED3);
}
/* ----------------------------------------------------------------------
** Loop here if the signals fail the PASS check.
** This denotes a test failure
** ------------------------------------------------------------------- */
if( status != ARM_MATH_SUCCESS)
{
while(1);
}
while(1)
{
STM_EVAL_LEDOn(LED6);
for (iCount = 0; iCount < 1000000; iCount++);
STM_EVAL_LEDOff(LED6);
for (iCount = 0; iCount < 1000000; iCount++);
}
}
void fft_adc(void){
uint16_t i;
//TODO:バッファをstaticにして関数切り出し．割り込みから呼ぶ，切り出し先はfft.c
arm_cfft_radix4_instance_f32 S; /* ARM CFFT module */
float32_t Input[FFT_SAMPLES];
uint32_t maxIndex; /* Index in Output array where max value is */
/* Initialize the CFFT/CIFFT module, intFlag = 0, doBitReverse = 1 */
arm_cfft_radix4_init_f32(&S, FFT_SIZE, 0, 1);
for (i = 0; i < FFT_SAMPLES; i += 2) {
Input[(uint16_t)i] = (float32_t)((float32_t)adc_buf[i/2] - (float32_t)2048.0) / (float32_t)2048.0;
Input[(uint16_t)(i + 1)] = 0;
}
/* Process the data through the CFFT/CIFFT module */
arm_cfft_radix4_f32(&S, Input);
/* Process the data through the Complex Magniture Module for calculating the magnitude at each bin */
arm_cmplx_mag_f32(Input, Output, FFT_SIZE);
/* Calculates maxValue and returns corresponding value */
arm_max_f32(Output, FFT_SIZE, &maxValue, &maxIndex);
//AD=79872sps/4096bit=19.5Hzステップでデータが格納される
}
void populateCoeficients(int bandwidth, int sideband, int offset)
{
//Chapter 17 of DSP Guide* //TODO: Make a bibliography!
//1. Take as input, desired filter response in array, both magnitude and phase (it's okay for phase to be zero)
// Looks like magnitude can be any non-negative value. First and last values of Phase must be zero.
//2. Convert to rectangular form. ***I really wish there was a built in function for this :<
//3. Run through an inverse FFT.
//4. Shift
//5. Truncate
//6. Window
//7. Reverse the FFT in preparation for FFT Convolution?
uint16_t filterKernelLength = 100; //what's a good value? How does it relate to the FFT size?
//1:
//sideband: 0 = LSB, 1 = USB, 2 = Both (AM)
//I think the code below is all wrong. At least for LSB, if the magnitude is zero, then phase doesn't matter, yeah?
if(sideband > 2) return; //Error
int i;
for(i = 0; i < FFT_BUFFER_SIZE; i++)
{
switch(sideband)
{
case 0:
if((i > FFT_BUFFER_SIZE - (offset + bandwidth)) && (i < FFT_BUFFER_SIZE - offset))
fftFilterCoeficient[i] = 1;
else
fftFilterCoeficient[i] = 0;
break;
case 1:
if((i > offset) && (i < offset + bandwidth))
fftFilterCoeficient[i] = 1;
else
fftFilterCoeficient[i] = 0;
break;
case 2:
if(((i > FFT_BUFFER_SIZE - (offset + bandwidth)) && (i < FFT_BUFFER_SIZE - offset))
|| ((i > offset) && (i < offset + bandwidth)))
fftFilterCoeficient[i] = 1;
else
fftFilterCoeficient[i] = 0;
break;
}
}
fftFilterCoeficient[FFT_BUFFER_SIZE / 2] = 0;
fftFilterCoeficient[FFT_BUFFER_SIZE - 1] = 0;
//return; //Skipping all the later stuff doesn't seem to make a huge difference yet...
//2:
// float x, y;
// for(i = 0; i < FFT_SIZE; i++)
// {
// polarToRect(fftFilterCoeficient[i], fftFilterCoeficient[FFT_BUFFER_SIZE - 1 - i], &x, &y);
// fftFilterCoeficient[i] = x;
// fftFilterCoeficient[FFT_BUFFER_SIZE - 1 - i] = y;
// }
//3:
arm_cfft_radix4_instance_f32 fft_co;
arm_cfft_radix4_init_f32(&fft_co, FFT_SIZE, 1, 1);
arm_cfft_radix4_f32(&fft_co, fftFilterCoeficient);
//4:
int index;
for (i = 0; i < FFT_BUFFER_SIZE; i++)
{
index = i + filterKernelLength/2;
if(index > FFT_BUFFER_SIZE - 1) index = index - FFT_BUFFER_SIZE;
filterTemp[index] = fftFilterCoeficient[i];
}
for(i = 0; i < FFT_BUFFER_SIZE; i++)
{
fftFilterCoeficient[i] = filterTemp[i];
}
//5 & 6:
for(i = 0; i < FFT_BUFFER_SIZE; i++)
{
if(i <= filterKernelLength) fftFilterCoeficient[i] =
fftFilterCoeficient[i] * (0.54 - 0.46 * arm_cos_f32(2.0 * 3.14159265 * i / filterKernelLength));
if(i > filterKernelLength) fftFilterCoeficient[i] = 0;
}
// arm_cfft_radix4_instance_f32 fft_co;
arm_cfft_radix4_init_f32(&fft_co, FFT_SIZE, 0, 1);
arm_cfft_radix4_f32(&fft_co, fftFilterCoeficient);
// for(i = 0; i < FFT_SIZE; i++)
// {
// filterTemp[i] = fftFilterCoeficient[i * 2];
// filterTemp[FFT_BUFFER_SIZE - 1 - i] = fftFilterCoeficient[i * 2 + 1];
// }
//
// for(i = 0; i < FFT_BUFFER_SIZE; i++)
// {
// fftFilterCoeficient[i] = filterTemp[i];
// }
}