蜂鸣器

 1 //beep.h
 2 #ifndef _BEEP_H_
 3 #define _BEEP_H_
 4 
 5 #define BEEP_ON (GPIOF->ODR |= (1<<8))
 6 #define BEEP_OFF (GPIOF->ODR &= ~(1<<8))
 7 
 8 void Beep_Init(void);
 9 void Delay(int n);
10 
11 #endif

 1 //beep.c
 2 #include "stm32f4xx.h"
 3 #include "beep.h"
 4 
 5 void Beep_Init(void)
 6 {
 7     //管脚外设时钟
 8     RCC->AHB1ENR |= (1<<5);    
 9     //PF8管脚状态
10     //模式配置
11     GPIOF->MODER &= ~(0X3<<16);    //清零
12     GPIOF->MODER |= (0X1<<16);    //PF8配置为通用输出状态
13     //输出类型配置
14     GPIOF->OTYPER &= ~(0X1<<8);    //推挽输出    
15     //速率配置
16     GPIOF->OSPEEDR &= ~(0X1<<16);
17     GPIOF->OSPEEDR |= (0X2<<16);    
18     //上下拉配置
19     GPIOF->PUPDR &= ~(0X3<<16);
20     GPIOF->PUPDR |= (0X1<<16);
21 }
22 
23 void Delay(int n)
24 {
25     while(n--);
26 }

 1 //main.c
 2 #include "stm32f4xx.h"
 3 #include "beep.h"
 4 
 5 int main()
 6 {    
 7     while(1)
 8     {    
 9         Beep_Init();
10         BEEP_ON;
11         Delay(1000000);
12         BEEP_OFF;
13         Delay(1000000);
14     }
15 }