stm32中用dsp做fft运算 - - Powered by Discuz!

/**
******************************************************************************
* @file FFT_Demo/src/main.c
* @author MCD Application Team
* @version V2.0.0
* @brief Main program body
/* Includes ------------------------------------------------------------------*/
#include "stm32f10x.h"
#include <math.h>
#include "stm3210b_lcd.h"
#include "stm32_dsp.h"
#include "table_fft.h"
/** @addtogroup FFT_Demo
* @{
*/
/* Private typedef -----------------------------------------------------------*/
/* Private define ------------------------------------------------------------*/
#define PI2 6.28318530717959
#define NPT 64 /* NPT = No of FFT point*/
#define DISPLAY_RIGHT 310 /* 224 for centered, 319 for right-aligned */
#define DISPLAY_LEFT 150 /* 224 for centered, 319 for right-aligned */
/* Private macro -------------------------------------------------------------*/
/* Private variables ---------------------------------------------------------*/
extern uint16_t TableFFT[];
extern volatile uint32_t TimingDelay ;
long lBUFIN[NPT]; /* Complex input vector */
long lBUFOUT[NPT]; /* Complex output vector */
long lBUFMAG[NPT + NPT/2];/* Magnitude vector */
/* Private function prototypes -----------------------------------------------*/
void MyDualSweep(uint32_t freqinc1,uint32_t freqinc2);
void MygSin(long nfill, long Fs, long Freq1, long Freq2, long Ampli);
void powerMag(long nfill, char* strPara);
void In_displayWaveform(uint32_t DisplayPos);
void Out_displayWaveform(uint32_t DisplayPos);
void displayPowerMag(uint32_t DisplayPos, uint32_t scale);
void DisplayTitle(void);
void DSPDemoInit(void);
/* Private functions ---------------------------------------------------------*/
/**
* @brief Main program.
* @param None
* @retval : None
*/
int main(void)
{
DSPDemoInit();
DisplayTitle();
while (1)
{
MyDualSweep(30,30);
}
}
/**
* @brief Produces a combination of two sinewaves as input signal
* @param eq1: frequency increment for 1st sweep
* Freq2: frequency increment for 2nd sweep
* @retval : None
*/
void MyDualSweep(uint32_t freqinc1,uint32_t freqinc2)
{
uint32_t freq;
for (freq=40; freq <4000; freq+=freqinc1)
{
MygSin(NPT, 8000, freq, 0, 32767);
GPIOC->BSRR = GPIO_Pin_7;
cr4_fft_64_stm32(lBUFOUT, lBUFIN, NPT);
GPIOC->BRR = GPIO_Pin_7;
powerMag(NPT,"2SIDED");
In_displayWaveform(DISPLAY_RIGHT);
displayPowerMag(DISPLAY_RIGHT, 9);
while (GPIO_ReadInputDataBit(GPIOB, GPIO_Pin_9) == 0x00);
}
for (freq=40; freq <4000; freq+=freqinc2)
{
MygSin(NPT, 8000, freq, 160, 32767/2);
GPIOC->BSRR = GPIO_Pin_7;
cr4_fft_64_stm32(lBUFOUT, lBUFIN, NPT);
GPIOC->BRR = GPIO_Pin_7;
powerMag(NPT,"2SIDED");
In_displayWaveform(DISPLAY_LEFT);
displayPowerMag(DISPLAY_LEFT, 8);
while (GPIO_ReadInputDataBit(GPIOB, GPIO_Pin_9) == 0x00);
}
}
/**
* @brief Produces a combination of two sinewaves as input signal
* @param ill: length of the array holding input signal
* Fs: sampling frequency
* Freq1: frequency of the 1st sinewave
* Freq2: frequency of the 2nd sinewave
* Ampli: scaling factor
* @retval : None
*/
void MygSin(long nfill, long Fs, long Freq1, long Freq2, long Ampli)
{
uint32_t i;
float fFs, fFreq1, fFreq2, fAmpli;
float fZ,fY;
fFs = (float) Fs;
fFreq1 = (float) Freq1;
fFreq2 = (float) Freq2;
fAmpli = (float) Ampli;
for (i=0; i < nfill; i++)
{
fY = sin(PI2 * i * (fFreq1/fFs)) + sin(PI2 * i * (fFreq2/fFs));
fZ = fAmpli * fY;
lBUFIN[i]= ((short)fZ) << 16 ; /* sine_cosine (cos=0x0) */
}
}
/**
* @brief Removes the aliased part of the spectrum (not tested)
* @param ill: length of the array holding power mag
* @retval : None
*/
void onesided(long nfill)
{
uint32_t i;
lBUFMAG[0] = lBUFMAG[0];
lBUFMAG[nfill/2] = lBUFMAG[nfill/2];
for (i=1; i < nfill/2; i++)
{
lBUFMAG[i] = lBUFMAG[i] + lBUFMAG[nfill-i];
lBUFMAG[nfill-i] = 0x0;
}
}
/**
* @brief Compute power magnitude of the FFT transform
* @param ill: length of the array holding power mag
* : strPara: if set to "1SIDED", removes aliases part of spectrum (not tested)
* @retval : None
*/
void powerMag(long nfill, char* strPara)
{
int32_t lX,lY;
uint32_t i;
for (i=0; i < nfill; i++)
{
lX= (lBUFOUT[i]<<16)>>16; /* sine_cosine --> cos */
lY= (lBUFOUT[i] >> 16); /* sine_cosine --> sin */
{
float X= 64*((float)lX)/32768;
float Y = 64*((float)lY)/32768;
float Mag = sqrt(X*X+ Y*Y)/nfill;
lBUFMAG[i] = (uint32_t)(Mag*65536);
}
}
if (strPara == "1SIDED") onesided(nfill);
}
/**
* @brief Displays the input array before filtering
* @param splayPos indicates the beginning Y address on LCD
* @retval : None
*/
void In_displayWaveform(uint32_t DisplayPos)
{
uint8_t aScale;
uint16_t cln;
for (cln=0; cln < 64; cln++) /* original upper limit was 60 */
{
/* Clear previous line */
LCD_SetTextColor(White);
LCD_DrawLine(48,DisplayPos-(2*cln),72,Vertical);
/* and go back to normal display mode */
LCD_SetTextColor(Black);
aScale = lBUFIN[cln]>>(10 + 16); /* SINE IS LEFT ALIGNED */
if (aScale > 127) /* Negative values */
{
aScale = (0xFF-aScale) + 1; /* Calc absolute value */
LCD_DrawLine(84-aScale,DisplayPos-(2*cln),aScale,Vertical);
}
else /* Display positive values */
{
LCD_DrawLine(84,DisplayPos-(2*cln),aScale,Vertical);
}
}/* for */
}
/**
* @brief Displays the output array after filtering
* @param splayPos indicates the beginning Y address on LCD
* @retval : None
*/
void Out_displayWaveform(uint32_t DisplayPos)
{
uint8_t aScale;
uint16_t cln;
for (cln=0; cln < 64; cln++) /* original upper limit was 60 */
{
aScale = lBUFOUT[cln]>>(10 + 16); /* SINE IS LEFT ALIGNED */
if (aScale > 127) /* Negative values */
{
aScale = (0xFF-aScale) + 1; /* Calc absolute value */
LCD_DrawLine(156-aScale,DisplayPos-(2*cln),aScale,Vertical);
}
else /* Display positive values */
{
LCD_DrawLine(156,DisplayPos-(2*cln),aScale,Vertical);
}
}/* for */
}
/**
* @brief Displays the power magnitude array following a FFT
* @param splayPos indicates the beginning Y address on LCD
* : scale allows to normalize the result for optimal display
* @retval : None
*/
void displayPowerMag(uint32_t DisplayPos, uint32_t scale)
{
uint16_t aScale;
uint16_t cln;
for (cln=0; cln < 64; cln++)
{
/* Clear previous line */
LCD_SetTextColor(White);
LCD_DrawLine(120,DisplayPos-(2*cln),72,Vertical);
/* and go back to normal display mode */
LCD_SetTextColor(Red);
aScale =lBUFMAG[cln]>>scale ; /* spectrum is always divided by two */
/* Power Mag contains only positive values */
LCD_DrawLine(192-aScale,DisplayPos-(2*cln),aScale,Vertical);
}/* for */
}
/**
* @brief Displays the initial menu and then background frame
* @param None
* @retval : None
*/
void DisplayTitle(void)
{
uint8_t *ptr = " STM32 DSP Demo ";
LCD_DisplayStringLine(Line0, ptr);
ptr = " 64-pts Radix-4 FFT ";
LCD_DisplayStringLine(Line1, ptr);
ptr = "Press Key to freeze ";
LCD_DisplayStringLine(Line9, ptr);
{
unsigned long long Delay = 0x600000;
while (Delay--);
while (GPIO_ReadInputDataBit(GPIOB, GPIO_Pin_9) == 0x00);
}
ptr = " Sine Dual sine ";
LCD_DisplayStringLine(Line9, ptr);
}
/**
* @brief Inserts a delay time.
* @param ount: specifies the delay time length (time base 10 ms).
* @retval : None
*/
void Delay(uint32_t nCount)
{
/* Configure the systick */
__enable_irq();
/* Setup SysTick Timer for 10 msec interrupts */
if (SysTick_Config(SystemFrequency /100)) /* SystemFrequency is defined in
搒ystem_stm32f10x.h?and equal to HCLK frequency */
{
/* Capture error */
while (1);
}
/* Enable the SysTick Counter */
TimingDelay = nCount;
while (TimingDelay ) {}
TimingDelay=0;
__disable_irq();
}
/**
* @brief Initializes the DSP lib demo (clock, peripherals and LCD).
* @param None
* @retval : None
*/
void DSPDemoInit(void)
{
GPIO_InitTypeDef GPIO_InitStructure;
ErrorStatus HSEStartUpStatus = ERROR;
/* SYSCLK, HCLK, PCLK2 and PCLK1 configuration -----------------------------*/
/* RCC system reset(for debug purpose) */
RCC_DeInit();
/* Enable HSE */
RCC_HSEConfig(RCC_HSE_ON);
/* Wait till HSE is ready */
HSEStartUpStatus = RCC_WaitForHSEStartUp();
if(HSEStartUpStatus == SUCCESS)
{
/* Enable Prefetch Buffer */
FLASH_PrefetchBufferCmd(FLASH_PrefetchBuffer_Enable);
/* Flash 2 wait state */
FLASH_SetLatency(FLASH_Latency_2);
/* HCLK = SYSCLK */
RCC_HCLKConfig(RCC_SYSCLK_Div1);
/* PCLK2 = HCLK */
RCC_PCLK2Config(RCC_HCLK_Div1);
/* PCLK1 = HCLK/2 */
RCC_PCLK1Config(RCC_HCLK_Div2);
/* PLLCLK = 8MHz * 9 = 72 MHz */
RCC_PLLConfig(RCC_PLLSource_HSE_Div1, RCC_PLLMul_9);
/* Enable PLL */
RCC_PLLCmd(ENABLE);
/* Wait till PLL is ready */
while(RCC_GetFlagStatus(RCC_FLAG_PLLRDY) == RESET)
{
}
/* Select PLL as system clock source */
RCC_SYSCLKConfig(RCC_SYSCLKSource_PLLCLK);
/* Wait till PLL is used as system clock source */
while(RCC_GetSYSCLKSource() != 0x08)
{
}
}
/* Enable GPIOA, GPIOB, GPIOC, GPIOD, GPIOE and AFIO clocks */
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA | RCC_APB2Periph_GPIOB |RCC_APB2Periph_GPIOC
| RCC_APB2Periph_GPIOD | RCC_APB2Periph_GPIOE | RCC_APB2Periph_AFIO, ENABLE);
/* TIM1 Periph clock enable */
RCC_APB2PeriphClockCmd(RCC_APB2Periph_TIM1, ENABLE);
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOC, ENABLE);
/* SPI2 Periph clock enable */
RCC_APB1PeriphClockCmd(RCC_APB1Periph_SPI2, ENABLE);
/* TIM2 and TIM4 clocks enable */
RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2 | RCC_APB1Periph_TIM4, ENABLE);
/*------------------- Resources Initialization -----------------------------*/
/* GPIO Configuration */
……………………
…………限于本文篇幅余下代码请从51黑下载附件…………

复制代码