#include "stm32f10x.h"
#include"led.h"
#include "sys.h"
#define LED13 PCout(13)
#define LED14 PCout(14)
void delay_ms(u32 i)
{
u32 temp;
SysTick->LOAD=9000*i; //设置重装数值, 72MHZ时
SysTick->CTRL=0X01; //使能,减到零是无动作,采用外部时钟源
SysTick->VAL=0; //清零计数器
do
{
temp=SysTick->CTRL; //读取当前倒计数值
}
while((temp&0x01)&&(!(temp&(1<<16)))); //等待时间到达
SysTick->CTRL=0; //关闭计数器
SysTick->VAL=0; //清空计数器
}
void LED_Init(void)
{
GPIO_InitTypeDef GPIO_InitStructure;
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB|RCC_APB2Periph_GPIOC, ENABLE);//使能PB,PE端口时钟
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_13|GPIO_Pin_14; //LED0-->PB.5 端口配置
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP; //推挽输出
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz; //IO口速度为50MHz
GPIO_Init(GPIOC, &GPIO_InitStructure); //根据设定参数初始化GPIOB.5
GPIO_SetBits(GPIOC,GPIO_Pin_14|GPIO_Pin_13); //PB.5 输出高
}
void TIM3_Int_Init(u16 arr,u16 psc)
{
TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
NVIC_InitTypeDef NVIC_InitStructure;
RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM3, ENABLE); //时钟使能
//定时器TIM3初始化
TIM_TimeBaseStructure.TIM_Period = arr; //设置在下一个更新事件装入活动的自动重装载寄存器周期的值
TIM_TimeBaseStructure.TIM_Prescaler =psc; //设置用来作为TIMx时钟频率除数的预分频值
TIM_TimeBaseStructure.TIM_ClockDivision = TIM_CKD_DIV1; //设置时钟分割:TDTS = Tck_tim
TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up; //TIM向上计数模式
TIM_TimeBaseInit(TIM3, &TIM_TimeBaseStructure); //根据指定的参数初始化TIMx的时间基数单位
TIM_ITConfig(TIM3,TIM_IT_Update,ENABLE ); //使能指定的TIM3中断,允许更新中断
//中断优先级NVIC设置
NVIC_InitStructure.NVIC_IRQChannel = TIM3_IRQn; //TIM3中断
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0; //先占优先级0级
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 3; //从优先级3级
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE; //IRQ通道被使能
NVIC_Init(&NVIC_InitStructure); //初始化NVIC寄存器
TIM_Cmd(TIM3, ENABLE); //使能TIMx
}
//定时器3中断服务程序
void TIM3_IRQHandler(u8 t) //TIM3中断
{
t=0;
t++;
if (TIM_GetITStatus(TIM3, TIM_IT_Update) != RESET) //检查TIM3更新中断发生与否
{
TIM_ClearITPendingBit(TIM3, TIM_IT_Update ); //清除TIMx更新中断标志
// delay_ms(1000);
LED13=!LED13;
if(t==60)
{
TIM_ITConfig(TIM3,TIM_IT_Update,DISABLE);
TIM_Cmd(TIM3, DISABLE);
t=0;
LED13=1;
}
}
}
int main(void)
{
LED_Init(); //LED端口初始化
TIM3_Int_Init(9999,7199);//10Khz的计数频率,计数到5000为500ms
while(1)
{
LED14=!LED14;
delay_ms(1000);
}
} |