#include "stm32f10x.h"
#include "time.h"
#include "stm32f10x_rcc.h"
#include "stm32f10x_gpio.h"
#include "misc.h"
void RCC_Config(void);
void GPIO_Config(void);
void TIM_Config(void);
void RCC_Config(void)
{
//使能GPIOB,TIM3
SystemInit();
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB,ENABLE);
RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM3,ENABLE);
RCC_APB2PeriphClockCmd(RCC_APB2Periph_AFIO,ENABLE);
}
void GPIO_Config(void)
{
//GPIO的配置我这里配置的是GPIOA_Pin_5
GPIO_InitTypeDef GPIO_InitStructure;
GPIO_InitStructure.GPIO_Pin=GPIO_Pin_5;
GPIO_InitStructure.GPIO_Mode=GPIO_Mode_AF_PP;
GPIO_InitStructure.GPIO_Speed=GPIO_Speed_50MHz;
GPIO_Init(GPIOB,&GPIO_InitStructure);
}
void TIM_Config(void)
{
TIM_TimeBaseInitTypeDef TIM_TImeBaseStructure;
TIM_OCInitTypeDef TIM_OCInitStructure;
GPIO_PinRemapConfig(GPIO_PartialRemap_TIM3,ENABLE);
//配置TIM2的时钟输出频率,以及其它相关参数初始化
TIM_TImeBaseStructure.TIM_Prescaler=360-1;//设置PWM的频率
TIM_TImeBaseStructure.TIM_CounterMode=TIM_CounterMode_Up;
TIM_TImeBaseStructure.TIM_Period=2000;
TIM_TimeBaseInit(TIM3,&TIM_TImeBaseStructure);
//设置PWM的输出方式
TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1;
TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_Low;
TIM_OC2PreloadConfig(TIM3, TIM_OCPreload_Enable);
//配置占空比
TIM_OCInitStructure.TIM_Pulse=50;
TIM_OC2Init(TIM3,&TIM_OCInitStructure);
TIM_Cmd(TIM3,ENABLE);
}
void Delay (uint32_t nCount)
{
for(; nCount != 0; nCount--);
}
int main(void)
{
u16 arr=2000;
u16 led_dt = arr/2;
RCC_Config(); //系统时钟初始化
GPIO_Config();//端口初始化
TIM_Config();//定时器和pwm配置
while(1)
{
TIM_SetCompare2(TIM3,led_dt); //用的是TIM3的通道2,输出PWM 送到相应的寄存器中 //满占空比为900
GPIO_SetBits(GPIOB,GPIO_Pin_5); //LED 发光
Delay(0x2ffff);
GPIO_ResetBits(GPIOB,GPIO_Pin_5);//LED 熄灭
Delay(0x2ffff);
}
}