一、定时器
1. 定义
设置等待时间，到达后则执行指定操作的硬件。
2. STM32F407的定时器有以下特征
具有基本的定时功能，也有PWM输出（灯光控制、电机的转速）、脉冲捕获功能（红外捕捉）。
2个高级控制定时器、10个通用定时器和2个基本定时器
高级控制定时器（TIM1和TIM8）
具有16位定时器功能，也具有PWM输出高级控制功能
通用定时器（TIM2到TIM5）
具有16位定时功能，也具有PWM输出控制功能
通用定时器（TIM9到TIM14）
具有16位定时功能，也具有PWM输出控制功能
基本定时器（TIM6和TIM7）
具有16位定时功能
二、定时器初始化
1. 选择时钟源，并初始化定时器分频值与定时时间
/* TIM3 clock enable ，定时器3时钟使能*/ RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM3, ENABLE); /* Time base configuration ，定时器基本配置*/ TIM_TimeBaseStructure.TIM_Period = (10000/1000)-1; //定时时间的设置[非常重要],中断频率为1000Hz，也就是定时时间为1ms TIM_TimeBaseStructure.TIM_Prescaler = 8400-1; //预分频值 TIM_TimeBaseStructure.TIM_ClockDivision = TIM_CKD_DIV1; //时钟分频，也称之为二次分频,当前是1分频，说白了不分频，不降低频率 TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up; //向上计数的方法 TIM_TimeBaseInit(TIM3, &TIM_TimeBaseStructure); //初始化
涉及部分寄存器参考如下
1. 中断的配置
/* TIM Interrupts enable,使能定时器3更新中断事件，也代表说定时已经到达的事件 */ TIM_ITConfig(TIM3, TIM_IT_Update, ENABLE); /* TIM3 enable counter，使能定时器3工作 */ TIM_Cmd(TIM3, ENABLE);
2. 中断服务函数的编写
void TIM3_IRQHandler(void)
{
static uint32_t cnt=0;
//是否已经有更新中断事件
if (TIM_GetITStatus(TIM3, TIM_IT_Update) == SET)
{
//添加用户代码
cnt++;
if(cnt>=500)
{
cnt =0;
PFout(9)^=1;
}
//清空标志位，告诉CPU我已经完成中断处理
TIM_ClearITPendingBit(TIM3, TIM_IT_Update);
}
}
TIM3
#include <stdio.h>
#include "stm32f4xx.h"
#include "sys.h"
GPIO_InitTypeDef GPIO_InitStructure;
TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
NVIC_InitTypeDef NVIC_InitStructure;
void tim3_init(void)
{
/* TIM3 clock enable ，定时器3时钟使能*/
RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM3, ENABLE);
/* Enable the TIM3 gloabal Interrupt ，使能定时器3全局中断*/
NVIC_InitStructure.NVIC_IRQChannel = TIM3_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1;
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStructure);
/* Time base configuration ，定时器基本配置*/
TIM_TimeBaseStructure.TIM_Period = (10000/1000)-1; //定时时间的设置[非常重要],中断频率为1000Hz，也就是定时时间为1ms
TIM_TimeBaseStructure.TIM_Prescaler = 8400-1; //预分频值
TIM_TimeBaseStructure.TIM_ClockDivision = TIM_CKD_DIV1; //时钟分频，也称之为二次分频,当前是1分频，说白了不分频，不降低频率
TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up; //向上计数的方法
TIM_TimeBaseInit(TIM3, &TIM_TimeBaseStructure); //初始化
/* TIM Interrupts enable,使能定时器3更新中断事件，也代表说定时已经到达的事件 */
TIM_ITConfig(TIM3, TIM_IT_Update, ENABLE);
/* TIM3 enable counter，使能定时器3工作 */
TIM_Cmd(TIM3, ENABLE);
}
int main(void)
{
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOF, ENABLE);
/* 配置PF9引脚为输出模式 */
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_9; //第9根引脚
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_OUT; //设置输出模式
GPIO_InitStructure.GPIO_OType = GPIO_OType_PP; //推挽模式，增加驱动电流
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_100MHz; //设置IO的速度为100MHz，频率越高性能越好，频率越低，功耗越低
GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL; //不需要上拉电阻
GPIO_Init(GPIOF, &GPIO_InitStructure);
PFout(9)=1;
//定时器3初始化
tim3_init();
while(1)
{
}
}
void TIM3_IRQHandler(void)
{
static uint32_t cnt=0;
//是否已经有更新中断事件
if (TIM_GetITStatus(TIM3, TIM_IT_Update) == SET)
{
//添加用户代码
cnt++;
if(cnt>=500)
{
cnt =0;
PFout(9)^=1;
}
//清空标志位，告诉CPU我已经完成中断处理
TIM_ClearITPendingBit(TIM3, TIM_IT_Update);
}
}
tim1238_irq
#include "stm32f4xx.h"
#include "stdio.h"
#include "bitband.h"
GPIO_InitTypeDef GPIO_InitStructure;
TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
NVIC_InitTypeDef NVIC_InitStructure;
void tim1_init(void)
{
RCC_APB2PeriphClockCmd(RCC_APB2Periph_TIM1, ENABLE);
NVIC_InitStructure.NVIC_IRQChannel = TIM1_UP_TIM10_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1;
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStructure);
//定时时间为100ms 168000000/16800=10000Hz
TIM_TimeBaseStructure.TIM_Period = (10000/10)-1;
TIM_TimeBaseStructure.TIM_Prescaler = 16800-1;
TIM_TimeBaseStructure.TIM_ClockDivision = TIM_CKD_DIV1;
TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
TIM_TimeBaseInit(TIM1, &TIM_TimeBaseStructure);
TIM_ITConfig(TIM1, TIM_IT_Update, ENABLE);
TIM_Cmd(TIM1, ENABLE);
}
void tim2_init(void)
{
RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2, ENABLE);
NVIC_InitStructure.NVIC_IRQChannel = TIM2_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1;
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStructure);
//定时时间为200ms 84000000/84000=10000Hz
TIM_TimeBaseStructure.TIM_Period = (10000/5)-1;
TIM_TimeBaseStructure.TIM_Prescaler = 8400-1;
TIM_TimeBaseStructure.TIM_ClockDivision = TIM_CKD_DIV1;
TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
TIM_TimeBaseInit(TIM2, &TIM_TimeBaseStructure);
TIM_ITConfig(TIM2, TIM_IT_Update, ENABLE);
TIM_Cmd(TIM2, ENABLE);
}
void tim3_init(void)
{
RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM3, ENABLE);
NVIC_InitStructure.NVIC_IRQChannel = TIM3_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1;
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStructure);
//定时时间为500ms 84000000/84000=10000Hz
TIM_TimeBaseStructure.TIM_Period = (10000/2)-1;
TIM_TimeBaseStructure.TIM_Prescaler = 8400-1;
TIM_TimeBaseStructure.TIM_ClockDivision = TIM_CKD_DIV1;
TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
TIM_TimeBaseInit(TIM3, &TIM_TimeBaseStructure);
TIM_ITConfig(TIM3, TIM_IT_Update, ENABLE);
TIM_Cmd(TIM3, ENABLE);
}
void tim8_init(void)
{
RCC_APB2PeriphClockCmd(RCC_APB2Periph_TIM8, ENABLE);
NVIC_InitStructure.NVIC_IRQChannel = TIM8_UP_TIM13_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1;
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStructure);
//定时时间为2秒 168000000/168000=10000Hz
TIM_TimeBaseStructure.TIM_Period = (10000*2)-1;
TIM_TimeBaseStructure.TIM_Prescaler = 16800-1;
TIM_TimeBaseStructure.TIM_ClockDivision = TIM_CKD_DIV1;
TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
TIM_TimeBaseInit(TIM8, &TIM_TimeBaseStructure);
TIM_ITConfig(TIM8, TIM_IT_Update, ENABLE);
TIM_Cmd(TIM8, ENABLE);
}
int main(void)
{
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOF | RCC_AHB1Periph_GPIOE, ENABLE);
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_9|GPIO_Pin_10;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_OUT;
GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_100MHz;
GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP;
GPIO_Init(GPIOF, &GPIO_InitStructure);
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_13|GPIO_Pin_14;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_OUT;
GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_100MHz;
GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP;
GPIO_Init(GPIOE, &GPIO_InitStructure);
PFout(9) = 1;
PFout(10) = 1;
PEout(13) = 1;
PEout(14) = 1;
tim1_init();
tim2_init();
tim3_init();
tim8_init();
while(1)
{
}
}
void TIM1_UP_TIM10_IRQHandler(void)
{
if (TIM_GetITStatus(TIM1, TIM_IT_Update) != RESET)
{
PFout(9) ^= 1;
TIM_ClearITPendingBit(TIM1, TIM_IT_Update);
}
}
void TIM2_IRQHandler(void)
{
if (TIM_GetITStatus(TIM2, TIM_IT_Update) != RESET)
{
PFout(10) ^= 1;
TIM_ClearITPendingBit(TIM2, TIM_IT_Update);
}
}
void TIM3_IRQHandler(void)
{
if (TIM_GetITStatus(TIM3, TIM_IT_Update) != RESET)
{
PEout(13) ^= 1;
TIM_ClearITPendingBit(TIM3, TIM_IT_Update);
}
}
void TIM8_UP_TIM13_IRQHandler(void)
{
if (TIM_GetITStatus(TIM8, TIM_IT_Update) != RESET)
{
PEout(14) ^= 1;
TIM_ClearITPendingBit(TIM8, TIM_IT_Update);
}
}
原文地址：https://www.cnblogs.com/xiangtingshen/p/10961427.html
时间： 2024-10-10 18:57:16