第八个实验 PWM控制蜂鸣器

配置PWM时应遵循以下步骤
1）将相应的GPIO管脚设为PWM模式
2）设置PWM模块时钟分频数
3）给PWM提供时钟
4）调用PWMGenConfigure配置PWM
5）调用PWMGenPeriodSet和PWMPulseWidthSet设置周期和脉宽
6）调用PWMOutputState使能PWM输出管脚
7）调用PWMGenEnable使能PWM模块

#include "stm32f10x.h"

int main()

{

 GPIO_InitTypeDef         GPIO_InitStructure;

 TIM_TimeBaseInitTypeDef  TIM_TimeBaseStructure;

 TIM_OCInitTypeDef        TIM_OCInitStructure;
//使能TIM2时钟
 RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2,ENABLE); 
//使能GPIOA和复用功能时钟

  RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);
设置GPIO模式

 GPIO_InitStructure.GPIO_Pin = GPIO_Pin_1; //TIM2¶þͨµÀPWM²¨ÐÎÊä³ö¶Ë¿ÚPA1

 GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;//¸´ÓÃÍÆÍìÊä³ö

 GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;//50MHz

 GPIO_Init(GPIOA, &GPIO_InitStructure);
//设置分频器基本单位结构体

 TIM_TimeBaseStructure.TIM_Period = 3600-1;//×Ô¶¯ÖØ×°ÔØÖµ£¬È¡Öµ±ØÐëÔÚ0x0000~0xFFFFÖ®¼ä

 TIM_TimeBaseStructure.TIM_Prescaler =10-1;//Ô¤·ÖƵֵ£¬+1Ϊ·ÖƵϵÊý£¬È¡Öµ±ØÐëÔÚ0x0000~0xFFFFÖ®¼ä       

 TIM_TimeBaseStructure.TIM_ClockDivision = 0;     //ʱÖÓ·Ö¸î

 TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up; //ÏòÉϼÆÊýģʽ 

 TIM_TimeBaseInit(TIM2, &TIM_TimeBaseStructure);

//设置基本单位结构体
 TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1;             //TIMÂö³å¿í¶Èµ÷ÖÆģʽ1

 TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable; //±È½ÏÊä³öʹÄÜ

 TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High;     //Êä³ö¼«ÐÔ:

 TIM_OCInitStructure.TIM_Pulse=900;          

 TIM_OC2Init(TIM2, &TIM_OCInitStructure);          //¸ù¾ÝTIM_OCInitStructÖÐÖ¸¶¨µÄ²ÎÊý³õʼ»¯ÍâÉèTIMx

 TIM_OC2PreloadConfig(TIM2, TIM_OCPreload_Enable); //ʹÄÜTIMxÔÚCCR2ÉϵÄԤװÔؼĴæÆ÷

 //使能TIx在ARR上的预装载寄存器

 TIM_ARRPreloadConfig(TIM2, ENABLE);          
//蜂鸣器不响              

 TIM_Cmd(TIM2, DISABLE); //½ûÖ¹TIM2ʹÄÜ
//蜂鸣器响  使能TIM2

  TIM_Cmd(TIM2, ENABLE);//ʹÄܶ¨Ê±Æ÷ 
//蜂鸣器不响

 TIM_Cmd(TIM2, DISABLE); //½ûÖ¹TIM2ʹÄÜ 
//蜂鸣器响

 TIM_Cmd(TIM2, ENABLE);//ʹÄܶ¨Ê±Æ÷ 
蜂鸣器不响

 TIM_Cmd(TIM2, DISABLE); //½ûÖ¹TIM2ʹÄÜ 

 

 

 }