ucos/APP/TIMER/timer.c

/***********************头文件****************************/
#include "timer.h"
#include "led.h"

/**************************************************
//通用定时器3中断初始化
//arr：自动重装值。
//psc：时钟预分频数
//定时器溢出时间计算方法:Tout=((arr+1)*(psc+1))/Ft us.
//Ft=定时器工作频率,单位:Mhz
//这里使用的是定时器3!
**************************************************/
void TIM3_Int_Init(u16 arr,u16 psc)
{
	TIM_TimeBaseInitTypeDef TIM_TimeBaseInitStructure;
	NVIC_InitTypeDef NVIC_InitStructure;
	RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM3,ENABLE);  //使能TIM3时钟	
    TIM_TimeBaseInitStructure.TIM_Period = arr; 	//自动重装载值
	TIM_TimeBaseInitStructure.TIM_Prescaler=psc;  //定时器分频
	TIM_TimeBaseInitStructure.TIM_CounterMode=TIM_CounterMode_Up; //向上计数模式
	TIM_TimeBaseInitStructure.TIM_ClockDivision=TIM_CKD_DIV1; 
	TIM_TimeBaseInit(TIM3,&TIM_TimeBaseInitStructure);//初始化TIM3	
	TIM_ITConfig(TIM3,TIM_IT_Update,ENABLE); //允许定时器3更新中断
	TIM_Cmd(TIM3,ENABLE); //使能定时器3
	NVIC_InitStructure.NVIC_IRQChannel=TIM3_IRQn; //定时器3中断
	NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority=0x01; //抢占优先级1
	NVIC_InitStructure.NVIC_IRQChannelSubPriority=0x03; //子优先级3
	NVIC_InitStructure.NVIC_IRQChannelCmd=ENABLE;
	NVIC_Init(&NVIC_InitStructure);
}