PWM输出蜂鸣器频率变声器

只看该作者 · 2024-11-19 11:00

一、工作原理：

1.利用STM32的定时器PWM输出通道，驱动蜂鸣器以特定频率发声，实现播放音乐的效果。

2.C调音符与频率对照表：

3.以下为常用的七声音阶频率(Hz)：

#define MC 262 Do

#define MD 294 Re

#define ME 330 Mi

#define MF 349 Fa

#define MG 392 Sol

#define MA 440 La

#define MB 494 Si

#define MCC 523 Do

二、软件设计：

1.蜂鸣器GPIO和定时器初始化

void PWM_Init_TIM1(u16 Psc,u16 Per){ GPIO_InitTypeDef GPIO_InitStruct; TIM_TimeBaseInitTypeDef TIM_TimeBaseInitStruct; TIM_OCInitTypeDef TIM_OCInitStruct; RCC_APB2PeriphClockCmd(PWMA_GPIO_CLK | PWMA_TIMx_CLK,ENABLE);//开启时钟 GPIO_InitStruct.GPIO_Mode=GPIO_Mode_AF_PP; // 初始化GPIO--PA8、PA11为复用推挽输出 GPIO_InitStruct.GPIO_Pin=PWMA_GPIO_PIN ; GPIO_InitStruct.GPIO_Speed=GPIO_Speed_50MHz; GPIO_Init(PWMA_GPIO_PORT,&GPIO_InitStruct); GPIO_ResetBits(PWMA_GPIO_PORT, PWMA_GPIO_PIN); TIM_TimeBaseStructInit(&TIM_TimeBaseInitStruct); // 初始化定时器。 TIM_TimeBaseInitStruct.TIM_ClockDivision=TIM_CKD_DIV1; TIM_TimeBaseInitStruct.TIM_CounterMode=TIM_CounterMode_Up; TIM_TimeBaseInitStruct.TIM_Period=Per; //arr TIM_TimeBaseInitStruct.TIM_Prescaler=Psc; TIM_TimeBaseInit(PWMA_TIMx,&TIM_TimeBaseInitStruct); // TIM1 TIM_OCInitStruct.TIM_OCMode=TIM_OCMode_PWM1; // 初始化输出比较 TIM_OCInitStruct.TIM_OCPolarity=TIM_OCPolarity_Low; TIM_OCInitStruct.TIM_OutputState=TIM_OutputState_Enable; TIM_OCInitStruct.TIM_Pulse=Per/2; TIM_OC1Init(PWMA_TIMx,&TIM_OCInitStruct); TIM_OC1PreloadConfig(PWMA_TIMx,TIM_OCPreload_Enable);// OC1预装载寄存器使能 TIM_ARRPreloadConfig(PWMA_TIMx,ENABLE);// TIM1在ARR上预装载寄存器使能 /*Open PWM output*/ TIM_CtrlPWMOutputs(PWMA_TIMx,ENABLE);// 高级定时器专属!!!--MOE主输出使能 TIM_Cmd(PWMA_TIMx,ENABLE); // 开定时器。 buzzerQuiet(); //关闭蜂鸣器}

2.控制蜂鸣器发声：

//compare:比较值void TIM_SetTIM1Compare1(u32 compare){ TIM1->CCR2=compare; } //设置TIM3通道2的arrvoid TIM_SetTIM1Autoreload(u32 Autoreload){ TIM1->ARR=Autoreload;} void buzzerQuiet(void)//停止发声{ buzzerSound(20000, 20);// TIM1->CCR2=0; // TIM_CtrlPWMOutputs(PWMA_TIMx,DISABLE);// TIM_Cmd(PWMA_TIMx,DISABLE); }void buzzerOpen(void)//发声{ TIM_CtrlPWMOutputs(PWMA_TIMx,ENABLE); TIM_Cmd(PWMA_TIMx,ENABLE); } void buzzerSound(unsigned short usFraq,unsigned char volume_level)//发声模块{ unsigned long Autoreload; buzzerOpen(); if((usFraq<=122)||(usFraq>20000)) { buzzerQuiet(); } else { Autoreload=(8000000/usFraq)-1; TIM_SetTIM1Autoreload(Autoreload); TIM_SetTIM1Compare1(Autoreload>>volume_level); }}

3.频率对照表宏定义：

#define LC 262#define LD 294#define LE 330#define LF 349#define LG 392#define LA 440#define LAP_LBN 466#define LB 494#define MC 523#define MD 587#define ME 659#define MEP 740#define MF 698#define MG 784#define MA 880#define MAP_MBN 932#define MB 988#define HC 1046#define HD 1175#define HE 1318#define HF 1397#define HG 1568#define HA 1760#define HB 1976

4.播放音乐(爱的罗曼史)：

uint16_t romance[96]={ ME,ME,ME, ME,MD,MC, MC,LB,LA, LA,MC,ME, MA,MA,MA, MA,MG,MD, MF,ME,MD, MD,ME,MF, ME,MF,ME, MEP,MF,ME, ME,MD,MC, MC,LB,LA, LB,LB,LB, LB,MC,LB, LA,LA,LA, LA,20000,20000, ME,ME,ME, ME,MD,MC, MC,LB,LB, LB,LAP_LBN,LB, MA,MA,MA, MA,MB,MA, MA,MG,MG, MG,MA,MB, HC,HC,HC, HC,MB,MAP_MBN, MA,MA,MA, MA,ME,MD, ME,ME,ME, ME,MF,MD, MC,MC,MC, MC,20000,20000}; void Romance(void){ uint16_t i=0; for(i=0; i<96; i++) { buzzerSound(romance, 200); delay_ms(150); buzzerQuiet(); delay_ms(150); } buzzerQuiet(); delay_ms(500);}