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基于STM32音频频谱分析设计

news 2025/6/13 18:01:45

基于STM32音频频谱分析设计

（程序＋原理图＋PCB＋设计报告）

功能介绍

具体功能：

采用咪头（话筒拾音传感器）采集音频信号，此音频信号过小，不利于单片机ADC直接采集，故将此音频信号经LM358放大电路放大后送入单片机的ADC口采集。

将采集到的音频信号进行量化，采用傅里叶变换，得出音频信号中的AD值频谱分布，

并将各段实时时间内的频谱分布数组以描点的方式显示在OLED屏幕之上。即可直观感受经傅里叶FFT变换分析得出的频谱显示。

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程序

/* Includes ------------------------------------------------------------------*/
#include "main.h"
#include "stm32f1xx_hal.h"
#include "adc.h"
#include "dma.h"
#include "tim.h"
#include "usart.h"
#include "gpio.h"
/***微信公众号：木子单片机****/
/* USER CODE BEGIN Includes */
#include "stm32_dsp.h"
#include "table_fft.h"
#include "math.h"
#include "oled.h"
#include "config.h"
#include "bg.h"
/* USER CODE END Includes *//* Private variables ---------------------------------------------------------*//* USER CODE BEGIN PV */
/* Private variables ---------------------------------------------------------*/
#define NPT 256
#define PI2 6.28318530717959
//采样率计算
//分辨率：Fs/NPT 
//#define Fs	10000
#define Fs	9984
//取9984能出来整数的分辨率 9984/256 = 39Hz/* USER CODE END PV *//* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
void Error_Handler(void);/* USER CODE BEGIN PFP */
/* Private function prototypes -----------------------------------------------*/
void Creat_Single(void);
void GetPowerMag(void);
void Single_Get(void);
void display1(void);
void display2(void);
void Key_Scan(void);
/* USER CODE END PFP *//* USER CODE BEGIN 0 */
uint32_t adc_buf[NPT]={0};long lBufInArray[NPT];
long lBufOutArray[NPT/2];
long lBufMagArray[NPT/2];uint8_t prt = 10;	//量化显示的比例
#define SHOW_NUM 4				//显示函数的个数
uint8_t display_num = 1;	//控制显示方式的
uint8_t auto_display_flag = 0;	//自动切换显示标志 1：自动切换 0:手动uint8_t fall_pot[128];	//记录下落点的坐标/* USER CODE END 0 */int main(void)
{/* USER CODE BEGIN 1 */uint16_t i = 0;/* USER CODE END 1 *//* MCU Configuration----------------------------------------------------------*//* Reset of all peripherals, Initializes the Flash interface and the Systick. */HAL_Init();/* Configure the system clock */SystemClock_Config();/* Initialize all configured peripherals */MX_GPIO_Init();MX_DMA_Init();MX_USART1_UART_Init();MX_ADC1_Init();MX_TIM3_Init();/* USER CODE BEGIN 2 */printf("uart test! \r\n");/*初始化显示*/GUI_Initialize();/*设置前景色和背景色 这里用1和0代替*/GUI_SetColor(1,0);GUI_LoadPic(0,0,(uint8_t *)&gImage_bg,128,64);GUI_Exec();HAL_Delay(3000);//初始化下落点 把下落的点 初始化为最底部显示for(i=0;i<128;i++)fall_pot[i] = 63;/*启动ADC的DMA传输 配合下面定时器来触发ADC转换*/HAL_ADC_Start_DMA(&hadc1, adc_buf, NPT);/*开启定时器 用溢出事件来触发ADC转换*/HAL_TIM_Base_Start(&htim3);/* USER CODE END 2 *//* Infinite loop *//* USER CODE BEGIN WHILE */while (1){/* USER CODE END WHILE *//* USER CODE BEGIN 3 */Key_Scan();}/* USER CODE END 3 */}/** System Clock Configuration
*/
void SystemClock_Config(void)
{RCC_OscInitTypeDef RCC_OscInitStruct;RCC_ClkInitTypeDef RCC_ClkInitStruct;RCC_PeriphCLKInitTypeDef PeriphClkInit;/**Initializes the CPU, AHB and APB busses clocks */RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSE;RCC_OscInitStruct.HSEState = RCC_HSE_ON;RCC_OscInitStruct.HSEPredivValue = RCC_HSE_PREDIV_DIV1;RCC_OscInitStruct.HSIState = RCC_HSI_ON;RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSE;RCC_OscInitStruct.PLL.PLLMUL = RCC_PLL_MUL9;if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK){Error_Handler();}/**Initializes the CPU, AHB and APB busses clocks */RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK|RCC_CLOCKTYPE_SYSCLK|RCC_CLOCKTYPE_PCLK1|RCC_CLOCKTYPE_PCLK2;RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV2;RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1;if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_2) != HAL_OK){Error_Handler();}PeriphClkInit.PeriphClockSelection = RCC_PERIPHCLK_ADC;PeriphClkInit.AdcClockSelection = RCC_ADCPCLK2_DIV6;if (HAL_RCCEx_PeriphCLKConfig(&PeriphClkInit) != HAL_OK){Error_Handler();}/**Configure the Systick interrupt time */HAL_SYSTICK_Config(HAL_RCC_GetHCLKFreq()/1000);/**Configure the Systick */HAL_SYSTICK_CLKSourceConfig(SYSTICK_CLKSOURCE_HCLK);/* SysTick_IRQn interrupt configuration */HAL_NVIC_SetPriority(SysTick_IRQn, 0, 0);
}/* USER CODE BEGIN 4 */
/************FFT相关*****************/
//测试用 生成一个信号
void Creat_Single(void)
{u16 i = 0;float fx=0.0;for(i=0; i<NPT; i++){fx = 2048+2048*sin(PI2 * i * 200.0 / Fs)+3100*sin(PI2 * i * 502.0 / Fs)+1300*sin(PI2 * i * 990.0 / Fs);lBufInArray[i] = ((signed short)fx) << 16;		}
}
//获取FFT后的直流分量
void GetPowerMag(void)
{signed short lX,lY;float X,Y,Mag;unsigned short i;for(i=0; i<NPT/2; i++){lX  = (lBufOutArray[i] << 16) >> 16;lY  = (lBufOutArray[i] >> 16);//除以32768再乘65536是为了符合浮点数计算规律X = NPT * ((float)lX) / 32768;Y = NPT * ((float)lY) / 32768;Mag = sqrt(X * X + Y * Y)*1.0/ NPT;if(i == 0)	lBufMagArray[i] = (unsigned long)(Mag * 32768);elselBufMagArray[i] = (unsigned long)(Mag * 65536);}
}
/*柱状显示*/
void display1(void)
{uint16_t i = 0;uint8_t x = 0;uint8_t y = 0;/*******************显示*******************/GUI_ClearSCR();for(i = 0; i < 32; i++)	//间隔的取32个频率出来显示{x = (i<<2);	//i*4y = 63-(lBufMagArray[x+1]/prt)-2;	//加1是为了丢掉第一个直流分量if(y>63) y = 63;GUI_LineWith(x,y,x,63,3,1);//画下落的点if(fall_pot[i]>y) fall_pot[i] = y;else{if(fall_pot[i]>63) fall_pot[i]=63;GUI_LineWith(x,fall_pot[i],x,fall_pot[i]+3,3,1);fall_pot[i] += 2 ;}}GUI_Exec();
}
/*单柱状显示*/
void display2(void)
{uint16_t i = 0;uint8_t y = 0;/*******************显示*******************/GUI_ClearSCR();for(i = 1; i < 128; i++)	{y = 63-(lBufMagArray[i]/prt)-2;if(y>63) y = 63;GUI_RLine(i,y,63,1);		//画下落的点if(fall_pot[i]>y) fall_pot[i] = y;else{if(fall_pot[i]>63) fall_pot[i]=63;GUI_RLine(i,fall_pot[i],fall_pot[i]+1,1);fall_pot[i] += 2 ;}}GUI_Exec();
}
/*柱状显示 中间对称*/
void display3(void)
{uint16_t i = 0;uint8_t y = 0;/*******************显示*******************/GUI_ClearSCR();for(i = 0; i < 127; i++)	{y = 31-(lBufMagArray[i+1]/prt)-2;	//加1是为了丢掉第一个直流分量if(y>31) y = 31;GUI_RLine(i,32,y,1);GUI_RLine(i,32,63-y,1);//画下落的点if(fall_pot[i]>y) fall_pot[i] = y;else{if(fall_pot[i]>30) fall_pot[i]=30;GUI_RLine(i,fall_pot[i],fall_pot[i]+1,1);GUI_RLine(i,63-fall_pot[i],63-(fall_pot[i]+1),1);fall_pot[i] += 2 ;}}GUI_Exec();
}
/*单柱状显示 中间对称*/
void display4(void)
{uint16_t i = 0;uint8_t x = 0;uint8_t y = 0;/*******************显示*******************/GUI_ClearSCR();for(i = 0; i < 32; i++)	//间隔的取32个频率出来显示{x = (i<<2);	//i*4y = 31-(lBufMagArray[x+1]/prt)-2;	//加1是为了丢掉第一个直流分量if(y>31) y = 31;GUI_LineWith(x,y,x,32,3,1);GUI_LineWith(x,63-y,x,32,3,1);//画下落的点if(fall_pot[i]>y) fall_pot[i] = y;else{if(fall_pot[i]>31) fall_pot[i]=31;GUI_LineWith(x,fall_pot[i],x,fall_pot[i]+3,3,1);GUI_LineWith(x,63 - fall_pot[i],x,63 - fall_pot[i]-3,3,1);fall_pot[i] += 2 ;}}GUI_Exec();
}//ADC DMA传输中断
void HAL_ADC_ConvCpltCallback(ADC_HandleTypeDef* hadc)
{uint16_t i = 0;static uint16_t num = 0;	
//	printf("adc dma interrupt \r\n");HAL_ADC_Stop_DMA(&hadc1);							//完成一次测量 关闭DMA传输//填充数组for(i=0;i<NPT;i++)lBufInArray[i] = ((signed short)(adc_buf[i]-2048)) << 16;		//这里因为单片机的ADC只能测正的电压 所以需要前级加直流偏执//加入直流偏执后 软件上减去2048即一半 达到负半周期测量的目的//cr4_fft_1024_stm32(lBufOutArray, lBufInArray, NPT);							//FFT变换cr4_fft_256_stm32(lBufOutArray, lBufInArray, NPT);GetPowerMag();																									//取直流分量对应的AD值
//	//打印出来测试
//	for(i=0;i<NPT/2;i++)
//		printf("i:%3d, f:%.2f, Power:%10d\r\n", i, (float)i*Fs/NPT, lBufMagArray[i]);//自动显示if(auto_display_flag == 1){if(num>300){num = 0;display_num ++;if(display_num>SHOW_NUM) display_num = 1;}}num++;//显示switch(display_num){case 1:display1();break;case 2:display2();break;case 3:display3();break;case 4:display4();break;default:display3();break;}HAL_ADC_Start_DMA(&hadc1, adc_buf, NPT);
}#define K1 HAL_GPIO_ReadPin(GPIOA,GPIO_PIN_3)
#define K2 HAL_GPIO_ReadPin(GPIOA,GPIO_PIN_4)
#define K3 HAL_GPIO_ReadPin(GPIOA,GPIO_PIN_5)void Key_Scan(void)
{static uint8_t mode_num = 0;if(K1 == RESET){HAL_Delay(10);if(K1 == RESET){while(!K1);mode_num=!mode_num;if(mode_num == 1) //自动显示模式{auto_display_flag = 1;GUI_PutString(0,0,"Auto");GUI_Exec();}else							//正常显示模式 手动切换效果{auto_display_flag = 0;GUI_PutString(0,0,"Manual");GUI_Exec();}}}if(K2 == RESET){HAL_Delay(10);if(K2 == RESET){while(!K2);if(mode_num == 0)	//手动模式 {display_num ++;if(display_num > SHOW_NUM) display_num = 1;}}}if(K3 == RESET){HAL_Delay(10);if(K3 == RESET){while(!K3);if(mode_num == 0)	//手动模式 {if(display_num == 1) display_num = SHOW_NUM+1;display_num --;}}}
}
/* USER CODE END 4 *//*** @brief  This function is executed in case of error occurrence.* @param  None* @retval None*/
void Error_Handler(void)
{/* USER CODE BEGIN Error_Handler *//* User can add his own implementation to report the HAL error return state */while(1) {}/* USER CODE END Error_Handler */ 
}
******//完整资料*//***微信公众号：木子单片机****/
#ifdef USE_FULL_ASSERT/*** @brief Reports the name of the source file and the source line number* where the assert_param error has occurred.* @param file: pointer to the source file name* @param line: assert_param error line source number* @retval None*/
void assert_failed(uint8_t* file, uint32_t line)
{/* USER CODE BEGIN 6 *//* User can add his own implementation to report the file name and line number,ex: printf("Wrong parameters value: file %s on line %d\r\n", file, line) *//* USER CODE END 6 */}#endif/*** @}*/ /*** @}
*/ /************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/

硬件设计

使用元器件：

单片机：STM32F103；