STM32F103C8T6 PWM的应用

#include "STM32f10x.h"
int main(void)
{
    GPIO_InitTypeDef GPIO_InitStruct;
    tiM_TimeBaseInitTypeDef TIM_TimeBaseInitStruct;
    TIM_OCInitTypeDef TIM_OCInitStruct;

    GPIO_InitStruct.GPIO_Mode = GPIO_Mode_AF_PP;
    GPIO_InitStruct.GPIO_Pin = GPIO_Pin_3;
    GPIO_InitStruct.GPIO_Speed = GPIO_Speed_50MHz;

    TIM_TimeBaseInitStruct.TIM_CounterMode = TIM_CounterMode_Down;
    TIM_TimeBaseInitStruct.TIM_Period = 10000-1;
    TIM_TimeBaseInitStruct.TIM_Prescaler = 72-1;
    //APB1=72MHz 则以上参数设置的周期为10ms,具体看时钟配置部分代码
    TIM_OCInitStruct.TIM_OCMode = TIM_OCMode_PWM2;
    TIM_OCInitStruct.TIM_OCPolarity = TIM_OCPolarity_Low;
    TIM_OCInitStruct.TIM_OutputState = ENABLE;
    TIM_OCInitStruct.TIM_Pulse = 0;

    RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2, ENABLE);
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_AFIO|RCC_APB2Periph_GPIOA, ENABLE);
    GPIO_Init( GPIOA, & GPIO_InitStruct);
    TIM_TimeBaseInit( TIM2, & TIM_TimeBaseInitStruct);
    TIM_OC4Init( TIM2, & TIM_OCInitStruct);
    TIM_Cmd( TIM2, ENABLE);

    while(1)
    {
        //根据配置：占空比=500/10000
        //仿真看看
        TIM_SetCompare4( TIM2, 500);
    }

}