07_TIM定时中断
TIM定时中断
TIM简介
定时器类型
基本定时器
通用定时器
高级定时器
基本定时器仅支持向上计数:0->重装值->发起中断
通用定时器和高级定时器支持向上计数,向下计数,中央对齐计数
向下计数:重装值->0->发起中断
中央对齐计数:0->重装值->发起中断->0->发起中断
基本定时器只能使用内部时钟(系统频率)72MHz
通用定时器可以使用内部时钟和外部时钟
定时中断基本结构
预分频器时序
计数器时序
计数器无预装时序
计数器有预装时序
RCC时钟树
定时器中断
接线图
代码
Timer.c
#include "stm32f10x.h" // Device header
void Timer_Init(void)
{
RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2,ENABLE); //使能时钟
TIM_InternalClockConfig(TIM2); //配置内部时钟
TIM_TimeBaseInitTypeDef TIM_TimeBaseInitStruct;
TIM_TimeBaseInitStruct.TIM_ClockDivision=TIM_CKD_DIV1; //时钟分频
TIM_TimeBaseInitStruct.TIM_CounterMode=TIM_CounterMode_Up; //向上计数
TIM_TimeBaseInitStruct.TIM_Period=10000-1; //自动重装器
TIM_TimeBaseInitStruct.TIM_Prescaler=7200-1; //预分频器
TIM_TimeBaseInitStruct.TIM_RepetitionCounter=0;
TIM_TimeBaseInit(TIM2,&TIM_TimeBaseInitStruct); //配置时基单元
TIM_ClearFlag(TIM2,TIM_FLAG_Update); //清除中断标志位,防止初始化时就会进一次中断
//中断配置
TIM_ITConfig(TIM2,TIM_IT_Update,ENABLE); //更新中断
//NVIC配置
NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2);
NVIC_InitTypeDef NVIC_InitStruct;
NVIC_InitStruct.NVIC_IRQChannel=TIM2_IRQn;
NVIC_InitStruct.NVIC_IRQChannelCmd=ENABLE;
NVIC_InitStruct.NVIC_IRQChannelPreemptionPriority=1;
NVIC_InitStruct.NVIC_IRQChannelSubPriority=1;
NVIC_Init(&NVIC_InitStruct);
//启动定时器
TIM_Cmd(TIM2,ENABLE);
}
/*
void TIM2_IRQHandler(void)
{
if(TIM_GetITStatus(TIM2,TIM_IT_Update)==SET)
{
TIM_ClearITPendingBit(TIM2,TIM_IT_Update);
}
}
*/
Timer.h
#ifndef __TIMER_H__
#define __TIMER_H__
void Timer_Init(void);
#endif
main.c
#include "stm32f10x.h" // Device header
#include "Delay.h"
#include "OLED.h"
#include "Timer.h"
uint16_t Num;
int main(void)
{
OLED_Init();
Timer_Init();
OLED_ShowString(1,1,"Num:");
while(1)
{
OLED_ShowNum(1,5,Num,5);
}
}
void TIM2_IRQHandler(void)
{
if(TIM_GetITStatus(TIM2,TIM_IT_Update)==SET)
{
Num++;
TIM_ClearITPendingBit(TIM2,TIM_IT_Update);
}
}
定时器外部时钟
接线图
原理图
代码
Timer.c
#include "stm32f10x.h" // Device header
void Timer_Init(void)
{
RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2,ENABLE); //使能时钟
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA,ENABLE);
GPIO_InitTypeDef GPIO_InitStruct;
GPIO_InitStruct.GPIO_Mode=GPIO_Mode_IPU;
GPIO_InitStruct.GPIO_Pin=GPIO_Pin_0;
GPIO_InitStruct.GPIO_Speed=GPIO_Speed_50MHz;
GPIO_Init(GPIOA,&GPIO_InitStruct);
TIM_ETRClockMode2Config(TIM2,TIM_ExtTRGPSC_OFF,TIM_ExtTRGPolarity_NonInverted,0); //外部时钟
TIM_TimeBaseInitTypeDef TIM_TimeBaseInitStruct;
TIM_TimeBaseInitStruct.TIM_ClockDivision=TIM_CKD_DIV1; //时钟分频
TIM_TimeBaseInitStruct.TIM_CounterMode=TIM_CounterMode_Up; //向上计数
TIM_TimeBaseInitStruct.TIM_Period=10-1; //自动重装器
TIM_TimeBaseInitStruct.TIM_Prescaler=1-1; //预分频器
TIM_TimeBaseInitStruct.TIM_RepetitionCounter=0;
TIM_TimeBaseInit(TIM2,&TIM_TimeBaseInitStruct); //配置时基单元
TIM_ClearFlag(TIM2,TIM_FLAG_Update); //清除中断标志位,防止初始化时就会进一次中断
//中断配置
TIM_ITConfig(TIM2,TIM_IT_Update,ENABLE); //更新中断
//NVIC配置
NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2);
NVIC_InitTypeDef NVIC_InitStruct;
NVIC_InitStruct.NVIC_IRQChannel=TIM2_IRQn;
NVIC_InitStruct.NVIC_IRQChannelCmd=ENABLE;
NVIC_InitStruct.NVIC_IRQChannelPreemptionPriority=1;
NVIC_InitStruct.NVIC_IRQChannelSubPriority=1;
NVIC_Init(&NVIC_InitStruct);
//启动定时器
TIM_Cmd(TIM2,ENABLE);
}
uint16_t Timer_GetCounter(void)
{
return TIM_GetCounter(TIM2);
}
/*
void TIM2_IRQHandler(void)
{
if(TIM_GetITStatus(TIM2,TIM_IT_Update)==SET)
{
TIM_ClearITPendingBit(TIM2,TIM_IT_Update);
}
}
*/
Timer.h
#ifndef __TIMER_H__
#define __TIMER_H__
void Timer_Init(void);
uint16_t Timer_GetCounter(void);
#endif
main.c
#include "stm32f10x.h" // Device header
#include "Delay.h"
#include "OLED.h"
#include "Timer.h"
uint16_t Num;
int main(void)
{
OLED_Init();
Timer_Init();
OLED_ShowString(1,1,"Num:");
OLED_ShowString(2,1,"CNT:");
while(1)
{
OLED_ShowNum(1,5,Num,5);
OLED_ShowNum(2,5,Timer_GetCounter(),5);
}
}
void TIM2_IRQHandler(void)
{
if(TIM_GetITStatus(TIM2,TIM_IT_Update)==SET)
{
Num++;
TIM_ClearITPendingBit(TIM2,TIM_IT_Update);
}
}