在定时器中断服务函数里加了个标志（flagTIMER），想看看中断了多少次，但是仿真一直是0（初始值），想问问大家这是问什么呢？

kmustH · 发表于 2019-11-10 14:40:04

timer.c文件：
#include "timer.h"
#include "delay.h"
#include "adc.h"

extern uint16_t flagTIMER;

void Timer_Init(void)
{
  TIM_TimeBaseInitTypeDef  TIM_TimeBaseStructure;
  NVIC_InitTypeDef       NVIC_InitStructure;

  RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2, ENABLE);

  TIM_Cmd(TIM2, DISABLE);
  TIM_TimeBaseStructInit(&TIM_TimeBaseStructure);

  //通用定时器时钟84MHz，分频系数84，计数频率1MHz，周期0.000001s,计数500次为0.5ms
  TIM_TimeBaseStructure.TIM_Prescaler = 84-1;
  TIM_TimeBaseStructure.TIM_Period = 500-1;
  TIM_TimeBaseStructure.TIM_ClockDivision = TIM_CKD_DIV1;
  TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up ;
  TIM_TimeBaseInit(TIM2, &TIM_TimeBaseStructure);

  TIM_ARRPreloadConfig(TIM2, ENABLE);
  TIM_SelectOutputTrigger(TIM2, TIM_TRGOSource_Update);

  TIM_Cmd(TIM2, ENABLE);

  NVIC_InitStructure.NVIC_IRQChannel = TIM2_IRQn;
  NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority=1;
  NVIC_InitStructure.NVIC_IRQChannelSubPriority =1;
  NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
  NVIC_Init(&NVIC_InitStructure);
}

void TIM2_IRQHandler(void)
{
  if(TIM_GetITStatus(TIM2, TIM_IT_Update))
  {
TIM_ClearITPendingBit(TIM2, TIM_IT_Update);
flagTIMER ++;
  }
}

main.c文件：
#include "stm32f4xx.h"
#include "delay.h"
#include "adc.h"
#include "dma.h"
#include "timer.h"

u16 flagTIMER = 0;
u16 flagDMA = 0;

int main(void)
{
  ADC_Config();
  DMA_Config();
  Timer_Init();
  while(1);
}