STM32L TIM 外部时钟模式不计数（STM32L-Discovery板子），什么问

只看该作者 · 2013-10-31 15:53

本帖最后由 god_carl 于 2013-10-31 15:56 编辑

GPIO_InitTypeDef  GPIO_InitStructure;
RCC_ClocksTypeDef RCC_ClockFreq;
TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;

GPIO_InitStructure.GPIO_Pin = GPIO_Pin_2;//
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_OUT;//_FLOATING; //
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_40MHz; //
GPIO_Init(GPIOA, &GPIO_InitStructure);

GPIO_InitStructure.GPIO_Pin = GPIO_Pin_2;//|GPIO_Pin_5|GPIO_Pin_15;//
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN;//_FLOATING; //
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_10MHz; //

      // GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
      //GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL;

GPIO_Init(GPIOD, &GPIO_InitStructure);
GPIO_PinAFConfig(GPIOD,GPIO_Pin_2,GPIO_AF_TIM3);



SystemInit();//??system_stm32f10x.c??,????????,????RCC???.
RCC_GetClocksFreq(&RCC_ClockFreq);

RCC_AHBPeriphClockCmd(RCC_AHBPeriph_GPIOA, ENABLE);
RCC_AHBPeriphClockCmd(RCC_AHBPeriph_GPIOD, ENABLE);

RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM3, ENABLE);

TIM_DeInit(TIM3);
TIM_TimeBaseStructure.TIM_Period = 0xFFFF;
TIM_TimeBaseStructure.TIM_Prescaler = 0x01;
TIM_TimeBaseStructure.TIM_ClockDivision = 0x0;
TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
TIM_TimeBaseInit(TIM3, &TIM_TimeBaseStructure); // Time base configuration

TIM_ETRClockMode2Config(TIM3, TIM_ExtTRGPSC_OFF, TIM_ExtTRGPolarity_NonInverted, 0);

TIM_SetCounter(TIM3, 100);
//TIM_ITConfig(TIM3, TIM_IT_Update, ENABLE);
TIM_Cmd(TIM3, ENABLE);

while(1)
{
   for(i_Loop = 0; i_Loop < 100; i_Loop ++)
   {
      GPIO_SetBits(GPIOA, GPIO_Pin_2);
      Delay(2);
      GPIO_ResetBits(GPIOA, GPIO_Pin_2);
      Delay(2);
   }

}
}

只看该作者 · 2013-10-31 16:22

换成TIM2 也不行  外部PA0，PA5，PA15管脚都试了，还是不计数，寄存器里可以看到这几个脚的电平变化，就是计数器不计数。下面是换TIM2的代码
  GPIO_InitTypeDef  GPIO_InitStructure;
RCC_ClocksTypeDef RCC_ClockFreq;
TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;

GPIO_InitStructure.GPIO_Pin = GPIO_Pin_2;//
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_OUT;//_FLOATING; //
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_40MHz; //
GPIO_Init(GPIOA, &GPIO_InitStructure);

GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0|GPIO_Pin_5|GPIO_Pin_15;//
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN;//_FLOATING; //
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_10MHz; //

      // GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
      // GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL;

GPIO_Init(GPIOA, &GPIO_InitStructure);
//GPIO_PinAFConfig(GPIOA,GPIO_Pin_2,GPIO_AF_TIM2);



SystemInit();//??system_stm32f10x.c??,????????,????RCC???.
RCC_GetClocksFreq(&RCC_ClockFreq);

RCC_AHBPeriphClockCmd(RCC_AHBPeriph_GPIOA, ENABLE);
//RCC_AHBPeriphClockCmd(RCC_AHBPeriph_GPIOD, ENABLE);

RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2, ENABLE);

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

TIM_ETRClockMode2Config(TIM2, TIM_ExtTRGPSC_OFF, TIM_ExtTRGPolarity_NonInverted, 0);

TIM_SetCounter(TIM2, 100);
TIM_ITConfig(TIM2, TIM_IT_Update, ENABLE);
TIM_Cmd(TIM2, ENABLE);

while(1)
{
   for(i_Loop = 0; i_Loop < 100; i_Loop ++)
   {
      GPIO_SetBits(GPIOA, GPIO_Pin_2);
      Delay(2);
      GPIO_ResetBits(GPIOA, GPIO_Pin_2);
      Delay(2);
   }

}
}

只看该作者 · 2013-10-31 16:24

没有人知道么？

1万 · 2013-10-31 21:36

芯片参考手册的定时器一章，有专门段落讲如何使用外部引脚上的信号作为计数器的时钟，【external clock source mode1】和【external clock source mode2】。

不是没人知道，只是这么大段代码贴上来，高兴看的估计不多。还是自己对照手册里描述的寄存器配置检查吧。