通用定时器外部计数模式,计数器一直没有启动,可以帮我看看是什么原因吗?

漂流 · 发表于 2019-10-20 14:00:50

#include "timer.h"
#include "led.h"
#include "stm32f10x.h"

//通用定时器2中断初始化
//这里时钟选择为APB1的2倍，而APB1为36M
//arr：自动重装值。
//psc：时钟预分频数
//这里使用的是定时器2!
u8  TIM2cnt = 0;
u32 TIM2value = 0;
u8 cnt = 0;
u8 sign = 0;
//外部计数TIM2
void TIM2_Int_Init(u16 arr,u16 psc)
{

GPIO_InitTypeDef GPIO_InitStructure;
NVIC_InitTypeDef NVIC_InitStructure;
TIM_TimeBaseInitTypeDef  TIM_TimeBaseStructure;
RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2, ENABLE); //时钟使能
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB,ENABLE);//使能PORTA时钟
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_3;//外部脉冲输入端口;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPU; //上拉输入
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz; //50M时钟速度
GPIO_Init(GPIOA, &GPIO_InitStructure);
GPIO_ResetBits(GPIOB,GPIO_Pin_3); //清楚指定数据端口位
TIM_DeInit(TIM2);
TIM_TimeBaseStructure.TIM_Period = arr;                //自动重装值
TIM_TimeBaseStructure.TIM_Prescaler =psc;                   //预分频值, 使TIMx_CLK=72MHz
TIM_TimeBaseStructure.TIM_ClockDivision = TIM_CKD_DIV1; //输入时钟不分频
TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;//向上计数
TIM_TimeBaseInit(TIM2, &TIM_TimeBaseStructure);             //TIM2_TimeBase

TIM_TIxExternalClockConfig(TIM2,TIM_TS_TI1FP1,TIM_ICPolarity_Rising, 0);//外部时钟触发输入上升沿有效  滤波

// TIM_SelectInputTrigger(TIM2,TIM_TS_ETRF); //TIM_TS_ETRF 外部触发输入

NVIC_InitStructure.NVIC_IRQChannel = TIM2_IRQn;  //TIM2中断
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 1;  //先占优先级2级
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 3;  //从优先级0级
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE; //IRQ通道被使能
NVIC_Init(&NVIC_InitStructure);  //根据NVIC_InitStruct中指定的参数初始化外设NVIC寄存器

TIM_SetCounter(TIM2,0);  //设置 TIM2 计数器寄存器值
TIM_ClearITPendingBit(TIM1,TIM_IT_Update); //清除中断标志位
TIM_ITConfig(TIM2,TIM_IT_Update,ENABLE); //使能TIM2更新中断
TIM_Cmd(TIM2,ENABLE);
}
void TIM3_Init(u16 arr,u16 psc)  //1s
{
TIM_TimeBaseInitTypeDef  TIM_TimeBaseStructure;
NVIC_InitTypeDef NVIC_InitStructure;

RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM3, ENABLE); //使能TIM3时钟
TIM_DeInit(TIM3);
TIM_TimeBaseStructure.TIM_Period = arr;
TIM_TimeBaseStructure.TIM_Prescaler =psc;             //TIMx_CLK=72MHz
TIM_TimeBaseStructure.TIM_ClockDivision = 0;          //
TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
TIM_TimeBaseInit(TIM3, &TIM_TimeBaseStructure);
TIM_ITConfig(TIM3,TIM_IT_Update,ENABLE);

NVIC_InitStructure.NVIC_IRQChannel = TIM3_IRQn;  //TIM3中断
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;  //先占优先级2级
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;  //从优先级0级
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE; //IRQ通道被使能
NVIC_Init(&NVIC_InitStructure);  //根据NVIC_InitStruct中指定的参数初始化外设NVIC寄存器
TIM_Cmd(TIM3,ENABLE);  //TIM3_TimeBase

}

//定时器2中断服务程序
void TIM2_IRQHandler(void) //TIM2中断
{
// if (TIM_GetITStatus(TIM2, TIM_IT_Update) != RESET)  //检查TIM3更新中断发生与否
// {
      TIM2cnt++;

      LED1 = ~LED1;
      TIM_ClearITPendingBit(TIM2, TIM_IT_Update);  //清除TIMx更新中断标志
// }
}
//定时器3服务函数
void TIM3_IRQHandler(void)
{
   cnt++;
   if(cnt == 20) //1s
   {
      cnt = 0;
      TIM2value=TIM_GetCounter(TIM2);
      TIM_Cmd(TIM2,DISABLE);
      TIM_Cmd(TIM3,DISABLE);
      LED0 = ~LED0;
      sign = 1;
   }
   TIM_ClearITPendingBit(TIM3,TIM_IT_Update); //清除中断标志位

}
//////////这是主函数/////
#include "led.h"
#include "delay.h"
#include "key.h"
#include "sys.h"
#include "usart.h"
#include "timer.h"
#include "stm32f10x.h"
u32 TIM2sum = 0;
int main(void)
{

delay_init();    //延时函数初始化
NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2); //设置NVIC中断分组2:2位抢占优先级，2位响应优先级
uart_init(115200);  //串口初始化为115200
LED_Init();    //LED端口初始化
TIM2_Int_Init(0XFFFF,0);
TIM3_Init(49999,71);//50ms
while(1)
{

      if(sign == 1)
      {
         TIM2sum = TIM2cnt*65536+TIM2value;
         sign = 0;
         printf("fre: %d\n",TIM2sum);
         TIM2sum = 0;
         TIM2cnt = 0;
         TIM2value = 0;
         TIM_SetCounter(TIM2,0);  //设置 TIM2 计数器寄存器值
         TIM_Cmd(TIM2,ENABLE);
         TIM_Cmd(TIM3,ENABLE);

      }

}

}