初学stm32外部计数模式，请指教

只看该作者 · 2013-11-26 14:10

最近两天在做外部计数，用的芯片stm32f107，希望采集100K~500K频率，之前没做过，网上好多例子只有部分代码没有说明，很郁闷。话不多说，这个程序总是不能出来数据。使用PA.0引脚来采集，用串口2，PA02 PA03输出信息，不知道哪里错了，希望大神能指正，最好能详细点，感激不尽
int main(void)
{
u16 i_Loop;
int n=0;

  RCC_Configuration();  // System Clocks Configuration

NVIC_Configuration();  // NVIC configuration

GPIO_Configuration();  // Configure the GPIO ports

USART1_Config();

Tim2_config();

while (1)
   {
   for(i_Loop = 0; i_Loop < 100; i_Loop ++)
  {
n = IC2Value;
  GPIO_SetBits(GPIOB, GPIO_Pin_0);
  Delay(10);
  GPIO_ResetBits(GPIOB, GPIO_Pin_0);
  Delay(10);
printf(" %d \n",n);

  }

}

}

void Tim2_config(void)
{
TIM_TimeBaseInitTypeDef  TIM_TimeBaseStructure;
//--------------设置------------------------

TIM_DeInit(TIM2);
// Time base configuration
TIM_TimeBaseStructure.TIM_Period = 0xFFFF;
TIM_TimeBaseStructure.TIM_Prescaler = 0x00;
TIM_TimeBaseStructure.TIM_ClockDivision = 0x0;
   //TIM_TimeBaseStructure.TIM_channel = TIM_Channel_1;
TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;

TIM_TimeBaseInit(TIM2, &TIM_TimeBaseStructure);

TIM_ETRClockMode2Config(TIM2, TIM_ExtTRGPSC_OFF, TIM_ExtTRGPolarity_NonInverted, 0);
//--------------测试---------------------------------------

TIM_SetCounter(TIM2, 0);
TIM_Cmd(TIM2, ENABLE);

}