有源和无源这里的“源”不是指电源，而是指震荡源。也就是说，有源蜂鸣器内部带震荡源，所以只要一通电就会叫。而无源内部不带震荡源，所以如果用直流信号无法令其鸣叫。必须用2K~5K的方波去驱动它。有源蜂鸣器往往比无源的贵，就是因为里面多个震荡电路。这就是通过驱动原理来分别的方法。
buzzer.h
#ifndef __BUZZER_H__
#define __BUZZER_H__#include "stm32l0xx_hal.h"//有源蜂鸣器引脚
#define BUZZER_PORT GPIOA
#define BUZZER_PIN GPIO_PIN_12typedef enum
{BUZZER_OFF = 0, // 停止BUZZER_ON, // 开始 }BUZZER_STATUE_E;typedef struct{BUZZER_STATUE_E Buzzer_SW; //蜂鸣器开关uint8_t Buzzer_Times; //蜂鸣器响的次数uint32_t Buzzer_DUR; //蜂鸣器响的时长uint32_t Buzzer_OFF_DUR; //蜂鸣器不响的时长 uint32_t Buzzer_TEMP;
}Buzzer_time_T;extern Buzzer_time_T Buzzer_time;void buzzer_ring(Buzzer_time_T *Buzzer_time_para); void set_buzzer(uint8_t sw,uint8_t times,uint32_t on_time,uint32_t off_time);#endifbuzzer.c
#include "buzzer.h"Buzzer_time_T Buzzer_time;//开蜂鸣器
static void open_buzzer(void)
{HAL_GPIO_WritePin(BUZZER_PORT, BUZZER_PIN, GPIO_PIN_SET);
}//关蜂鸣器
static void close_buzzer(void)
{HAL_GPIO_WritePin(BUZZER_PORT, BUZZER_PIN, GPIO_PIN_RESET);
}/*********************************************************
根据结构体Buzzer_time的Buzzer_SW、Buzzer_DUR、Buzzer_Times
三个参数确定蜂鸣器开关、每次时长和次数
*********************************************************/
void buzzer_ring(Buzzer_time_T *Buzzer_time_para)
{static uint8_t flag, times_flag;if(Buzzer_time_para->Buzzer_SW){if((Buzzer_time_para->Buzzer_Times) && (times_flag == 0)){ if(!flag){flag = 1;open_buzzer();Buzzer_time_para->Buzzer_TEMP = HAL_GetTick();}if(HAL_GetTick()-Buzzer_time_para->Buzzer_TEMP > Buzzer_time_para->Buzzer_DUR){flag = 0;Buzzer_time_para->Buzzer_Times--;close_buzzer(); if(Buzzer_time_para->Buzzer_Times == 0){Buzzer_time_para->Buzzer_SW = BUZZER_OFF; Buzzer_time_para->Buzzer_DUR = 0; times_flag = 0;}else{times_flag = 1; }}}else if((Buzzer_time_para->Buzzer_Times) && (times_flag == 1)){if(HAL_GetTick()-Buzzer_time_para->Buzzer_TEMP > (Buzzer_time_para->Buzzer_DUR + Buzzer_time_para->Buzzer_OFF_DUR)) {times_flag = 0;}}}else{close_buzzer();}
}/*********************************************************
设置蜂鸣器响的次数及相应时长
*********************************************************/
void set_buzzer(BUZZER_STATUE_E sw,uint8_t times,uint32_t on_time,uint32_t off_time)
{Buzzer_time.Buzzer_SW = sw;Buzzer_time.Buzzer_Times = times; Buzzer_time.Buzzer_DUR = on_time;Buzzer_time.Buzzer_OFF_DUR = off_time;
}//for simple test
void test_buzzer(void)
{set_buzzer(BUZZER_ON,3,1000,1000); while(1){buzzer_ring(&Buzzer_time);}
}
