香主能帮忙看看吗？---正交编码的问题

只看该作者 · 2008-11-16 16:52

我用的是KEIL，代码基本是抄自正交编码接口应用笔记,代码中只用了一个TIM3,没有开任何中断。

运行KEIL的Simulator (没有设置断点), 并在端口PA6（TIM3_CH1）和PA7(TIM3_CH2)上按如下顺序输入信号模拟正交编码器
PA6  1  1  0  0  1  1  0  0
PA7  0  1  1  0  0  1  1  0
或者逆序：
PA6  0  1  1  0  0  1  1  0
PA7  1  1  0  0  1  1  0  0
都没有得到TIM3计数器值(程序中是eCounter )的更新，但如果在程序中加入读取PA6和PA7的代码，是可以看到PA6和PA7是按上述顺序更新的。
大家帮忙看看是哪里出了问题。先谢谢了！

附注：
STM32F10xxx 正交编码器接口应用笔记链接如下 http://www.stmicroelectronics.com.cn/stonline/mcu/images/STM32F10xxx_Encoder_AN(CH).pdf

http://www.stmicroelectronics.com.cn/stonline/mcu/images/STM32F10xxx_Encoder_AN(CH).zip

俺的程序：

int main(void)
{

#ifdef DEBUG
  debug();
#endif

  /* Configure the system clocks */
  RCC_Configuration();

  /* NVIC Configuration */
  NVIC_Configuration();

  ENC_Init();

  eCounter = TIM3->CNT;
  eTemp =0;
  while(1)
  {
   eTemp++;
   if (eTemp==100000)
   {
   eTemp=0;
   eCounter = TIM3->CNT;
   //eCounter = TIM_GetCounter(TIM3);
   }
  }
}

void ENC_Init(void)
{
  TIM_TimeBaseInitTypeDef  TIM_TimeBaseStructure;
  TIM_ICInitTypeDef TIM_ICInitStructure;

  /* Encoder unit connected to TIM3, 4X mode */
  GPIO_InitTypeDef GPIO_InitStructure;
  NVIC_InitTypeDef NVIC_InitStructure;

  /* TIM3 clock source enable */
  RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM3, ENABLE);
  /* Enable GPIOA, clock */
  RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA|RCC_APB2Periph_AFIO, ENABLE);

  GPIO_StructInit(&GPIO_InitStructure);
  /* Configure PA.06,07 as encoder input */
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6 | GPIO_Pin_7;
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;
  GPIO_Init(GPIOA, &GPIO_InitStructure);

  /* Enable the TIM3 Update Interrupt */
// NVIC_InitStructure.NVIC_IRQChannel = TIM3_IRQChannel;
  //NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 1;
  //NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
// NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
// NVIC_Init(&NVIC_InitStructure);

  /* Timer configuration in Encoder mode */
  // TIM_DeInit(TIM3);
  //TIM_TimeBaseStructInit(&TIM_TimeBaseStructure);

  TIM_TimeBaseStructure.TIM_Prescaler = 0x0;  // No prescaling
  TIM_TimeBaseStructure.TIM_Period = (4*125)-1;
  TIM_TimeBaseStructure.TIM_ClockDivision = 0;
  TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
  TIM_TimeBaseInit(TIM3, &TIM_TimeBaseStructure);

  TIM_EncoderInterfaceConfig(TIM3, TIM_EncoderMode_TI12,
                             TIM_ICPolarity_Rising, TIM_ICPolarity_Rising);
  TIM_ICStructInit(&TIM_ICInitStructure);
  TIM_ICInitStructure.TIM_ICFilter = 6;
  TIM_ICInit(TIM3, &TIM_ICInitStructure);

  // Clear all pending interrupts
  //TIM_ClearFlag(TIM3, TIM_FLAG_Update);
  //TIM_ITConfig(TIM3, TIM_IT_Update, ENABLE);
  //Reset counter
  //TIM3->CNT = 0;

  //ENC_Clear_Speed_Buffer();

  TIM_Cmd(TIM3, ENABLE);
}