pwm输出控制灯的暗灭

#include\"stm32f10x.h\"

void Rcc_Configuration(void); void GPIO_Configuration(void); void tim3_Configuration(void); void delay(void); int main(void) {

u8 led_fx=1; u16 led_dt=0;

Rcc_Configuration(); GPIO_Configuration(); tim3_Configuration(); while(1) {

if(led_fx==1) {

led_dt++; } else {

led_dt--; }

if(led_dt>300) led_fx=0; if(led_dt==0) led_fx=1;

TIM_SetCompare3(TIM2,led_dt);//led_dt改变ccrx寄存器内的值 delay(); }

}

void Rcc_Configuration(void) {

SystemInit();

RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB,ENABLE); RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2,ENABLE); RCC_APB2PeriphClockCmd(RCC_APB2Periph_AFIO,ENABLE); }

void GPIO_Configuration(void) {

GPIO_InitTypeDef GPIO_InitStructure;

GPIO_InitStructure.GPIO_Pin=GPIO_Pin_10;

GPIO_InitStructure.GPIO_Speed=GPIO_Speed_50MHz;

GPIO_InitStructure.GPIO_Mode=GPIO_Mode_AF_PP;//必须配置成复用输出模式 GPIO_Init(GPIOB,&GPIO_InitStructure); }

void tim3_Configuration(void) {

TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure; TIM_OCInitTypeDef TIM_OCInitStructure;