[应用相关] STM32PWM输出实现LED灯渐亮渐灭

*说明：

*PA0:KEY1;PA1:KEY2;

*PA2:LED1;PA3:LED2;

*PA9:USART1_TX;PA10:USART1_RX

*/

#include "stm32f10x.h"

#include "stm32f10x_rcc.h"

#include "stm32f10x_gpio.h"

#include "stm32f10x_tim.h"

#include "stm32f10x_pwr.h"

#include "stm32f10x_exti.h"

#include "system_stm32f10x.h"

#include "misc.h"



void RCC_Configuration(void);

void GPIO_Configuration(void); 

void TIM2_Configuration(void);

void delay_ms(u16 time);



int main()

{

    u8 led_fx=1;

    u16 led_dt=0;

    

    RCC_Configuration();

    GPIO_Configuration(); 

    TIM2_Configuration();

                

    while(1)

    {

      delay_ms(10);

      if(led_fx==1)

      {

        led_dt++;

      }else{

        led_dt--;

      }

      

      if(led_dt>100) led_fx=0;//可以和初始值一样

      if(led_dt==0)  led_fx=1;

      

      TIM_SetCompare3(TIM2,led_dt);//通道3没有重影像是PA2对应LED1

      TIM_SetCompare4(TIM2,led_dt);//通道4没有重影像是PA3对应LED2

    }

}



void RCC_Configuration(void)  

{   

  SystemInit();

  RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA,ENABLE);   

  RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2,ENABLE); 

  //GPIO_AFIODeInit();和下面相同效果，可以查看源码证明

  RCC_APB2PeriphClockCmd(RCC_APB2Periph_AFIO,ENABLE); 

} 



void GPIO_Configuration(void)  

{  

  GPIO_InitTypeDef GPIO_InitStructure;  

  

  //GPIO_PinRemapConfig(GPIO_PartialRemap2_TIM2,ENABLE);//端口映射函数

  

  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_2|GPIO_Pin_3;//GPIO_Pin_3对应channel3，主函数改为：TIM_SetCompare3 

  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;

  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;

  GPIO_Init(GPIOA, &GPIO_InitStructure); 

}



void TIM2_Configuration(void)  

{

  TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;

  TIM_OCInitTypeDef TIM_OCInitStructure;

  

  TIM_DeInit(TIM2);

  TIM_InternalClockConfig(TIM2);

  //定时器初始化

  TIM_TimeBaseStructure.TIM_Period = 100-1;//初始值是100,2MHz=2000KHz,2MHz/100=0.02MHz,所有周期T=1/0.02MHz=50us,示波器显示周期应该为50us

  TIM_TimeBaseStructure.TIM_Prescaler = 36-1;//36倍分频，72MHz/36=2MHz

  TIM_TimeBaseStructure.TIM_ClockDivision = 0;

  TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;

  TIM_TimeBaseStructure.TIM_RepetitionCounter = 0;

  TIM_TimeBaseInit(TIM2, &TIM_TimeBaseStructure);

  

  //PWM初始化

  TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1;

  TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;

  TIM_OCInitStructure.TIM_Pulse = 50;//占空比值是50，所以占空比是：50/100=50%

  TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_Low;

  TIM_OC3Init(TIM2,&TIM_OCInitStructure);

  

  TIM_OCInitStructure.TIM_Pulse = 20;

  TIM_OC4Init(TIM2,&TIM_OCInitStructure);

  //TIM_OC3PreloadConfig(TIM2,TIM_OCPreload_Enable);

  //TIM_ARRPreloadConfig(TIM2, ENABLE); 

  TIM_Cmd(TIM2,ENABLE);

  TIM_CtrlPWMOutputs(TIM2,ENABLE);

}

void delay_ms(u16 time)   

{  

  u16 i=0;  

  while(time--)   

  {  

    i=12000;  

    while(i--);  

  }  

}  

</font>

#ifndef __STM32F10x_IT_H

#define __STM32F10x_IT_H



/* Includes ------------------------------------------------------------------*/

/* Exported types ------------------------------------------------------------*/

/* Exported constants --------------------------------------------------------*/

/* Exported macro ------------------------------------------------------------*/

/* Exported functions ------------------------------------------------------- */  

void NMIException(void);

void HardFaultException(void);

void MemManageException(void);

void BusFaultException(void);

void UsageFaultException(void);

void DebugMonitor(void);

void SVCHandler(void);

void PendSVC(void);

void SysTickHandler(void);

void WWDG_IRQHandler(void);

void PVD_IRQHandler(void);

void TAMPER_IRQHandler(void);

void RTC_IRQHandler(void);

void FLASH_IRQHandler(void);

void RCC_IRQHandler(void);

void EXTI0_IRQHandler(void);

void EXTI1_IRQHandler(void);

void EXTI2_IRQHandler(void);

void EXTI3_IRQHandler(void);

void EXTI4_IRQHandler(void);

void DMA1_Channel1_IRQHandler(void);

void DMA1_Channel2_IRQHandler(void);

void DMA1_Channel3_IRQHandler(void);

void DMA1_Channel4_IRQHandler(void);

void DMA1_Channel5_IRQHandler(void);

void DMA1_Channel6_IRQHandler(void);

void DMA1_Channel7_IRQHandler(void);

void ADC1_2_IRQHandler(void);

void USB_HP_CAN_TX_IRQHandler(void);

void USB_LP_CAN_RX0_IRQHandler(void);

void CAN_RX1_IRQHandler(void);

void CAN_SCE_IRQHandler(void);

void EXTI9_5_IRQHandler(void);

void TIM1_BRK_IRQHandler(void);

void TIM1_UP_IRQHandler(void);

void TIM1_TRG_COM_IRQHandler(void);

void TIM1_CC_IRQHandler(void);

void TIM2_IRQHandler(void);

void TIM3_IRQHandler(void);

void TIM4_IRQHandler(void);

void I2C1_EV_IRQHandler(void);

void I2C1_ER_IRQHandler(void);

void I2C2_EV_IRQHandler(void);

void I2C2_ER_IRQHandler(void);

void SPI1_IRQHandler(void);

void SPI2_IRQHandler(void);

void USART1_IRQHandler(void);

void USART2_IRQHandler(void);

void USART3_IRQHandler(void);

void EXTI15_10_IRQHandler(void);

void RTCAlarm_IRQHandler(void);

void USBWakeUp_IRQHandler(void);

void TIM8_BRK_IRQHandler(void);

void TIM8_UP_IRQHandler(void);

void TIM8_TRG_COM_IRQHandler(void);

void TIM8_CC_IRQHandler(void);

void ADC3_IRQHandler(void);

void FSMC_IRQHandler(void);

void SDIO_IRQHandler(void);

void TIM5_IRQHandler(void);

void SPI3_IRQHandler(void);

void UART4_IRQHandler(void);

void UART5_IRQHandler(void);

void TIM6_IRQHandler(void);

void TIM7_IRQHandler(void);

void DMA2_Channel1_IRQHandler(void);

void DMA2_Channel2_IRQHandler(void);

void DMA2_Channel3_IRQHandler(void);

void DMA2_Channel4_5_IRQHandler(void);

                                         

#endif /* __STM32F10x_IT_H */



/******************* (C) COPYRIGHT 2008 STMicroelectronics *****END OF FILE****/