STM32电子齿轮实现方法试验

只看该作者 · 2014-5-22 15:01

最近几天一直在关注运动控制器的事，纠结这个电子齿轮是怎么实现的，就用STM32试了一下。
我的想法是捕获每个输入脉冲的周期，然后根据齿轮比计算输出脉冲的周期实现输出。测试程序贴在下面。其中用TIM2完成编码器四倍频的程序，同时捕获四倍频后单个脉冲的周期。TIM1实现通过比较输出的PWM模式1实现根据齿轮比换算后的脉冲输出。
我的编码器是600线，四倍频后是2400个脉冲每转，步进电机设定为1200步每转，这样为了编码器和步进电机同速度旋转，只要输出脉冲周期是输入脉冲周期的2倍就可以了，其他的齿轮比就是一个乘法，一个除法，计算也很快的。
目前的问题是，这样做速度基本可以说是同步了，但是位置并不能保证同步，不是严格意义上的电子齿轮。不知道现在的电子齿轮实际是怎么实现的，查了资料看应该是FPGA来实现，思路是这样吗？如果是我也试一下。希望大家多多指点。

#define PPSIN (GPIOA->IDR & 0x03)

u32 tempTIMIndex;
u32 tempTIM[4];

uint32_t ppState;
uint32_t ppState2;
const uint32_t ppStateTab[4] = {0x02, 0x00, 0x03, 0x01};
//const uint32_t ppStateTab[4] = {0x01, 0x03, 0x00, 0x02};

//编码器输入配置
void SSINInit(void)
{
RCC->APB2ENR |= RCC_APB2ENR_IOPAEN;//使能GPIOA的时钟
  RCC->APB1ENR |= RCC_APB1ENR_TIM2EN;//使能TIM2的时钟

  GPIOA->ODR |= GPIO_ODR_ODR0 + GPIO_ODR_ODR1;
GPIOA->CRL &= ~((GPIO_CRL_MODE0_0 * mode_reset) + (GPIO_CRL_MODE1_0 * mode_reset));
GPIOA->CRL |= ((GPIO_CRL_MODE0_0 * pull_in) + (GPIO_CRL_MODE1_0 * pull_in));

//时基模式
  TIM2->CNT = 0;
TIM2->PSC = 0;
TIM2->ARR = 0xffff;
TIM2->CR1 = TIM_CR1_CKD_1+TIM_CR1_URS;//边沿向上计数,选择更新源

  //信号输入、滤波
  TIM2->CCMR1 =  TIM_CCMR1_CC1S_0//IC1映射在TI1
               //+ TIM_CCMR1_IC1F_3//采样频率及滤波长度
               //+ TIM_CCMR1_IC1F_2
               //+ TIM_CCMR1_IC1F_1
               //+ TIM_CCMR1_IC1F_0
               + TIM_CCMR1_CC2S_0//IC2映射在IT2
               //+ TIM_CCMR1_IC2F_3//采样频率及滤波长度
               //+ TIM_CCMR1_IC2F_2
               //+ TIM_CCMR1_IC2F_1
               //+ TIM_CCMR1_IC2F_0
               ;
TIM2->CCER =  TIM_CCER_CC1E//捕获
            + TIM_CCER_CC2E
               //+ TIM_CCER_CC1P
               //+ TIM_CCER_CC2P
               ;
TIM2->SMCR =  TIM_SMCR_TS_0//配置从模式为复位模式
            + TIM_SMCR_TS_2
               + TIM_SMCR_SMS_2
               ;
//配置中断
  NVIC_SetPriority(TIM2_IRQn, 1);
NVIC_EnableIRQ(TIM2_IRQn);

//初始化并开启
  TIM2->EGR |= TIM_EGR_UG;//初始化缓冲寄存器
  TIM2->SR &= ~(TIM_SR_CC1IF + TIM_SR_CC2IF + TIM_SR_UIF);//清除CC1 CC2捕获中断标志、更新中断标志
  TIM2->DIER |= (TIM_DIER_CC1IE + TIM_DIER_CC2IE + TIM_DIER_UIE);//开启CC1 CC2捕获中断、更新中断
  TIM2->CR1 |= TIM_CR1_CEN;//开启TIM2
}

//编码器输入中断
void TIM2_IRQHandler(void)
{
if (TIM2->SR & TIM_SR_CC1IF)
{
   TIM2->SR &= ~TIM_SR_CC1IF;
   ppState = PPSIN;
   if (ppStateTab[ppState] == ppState2)
   {
   Y10 = !Y10;
   ppState2 = ppState;
   TIM2->CCER ^=  TIM_CCER_CC1P;//切换边沿
   TIM2->SMCR &=  ~TIM_SMCR_TS_0;//切换复位信号
   TIM2->SMCR |=  TIM_SMCR_TS_1;

   //totalCounter = ((TIM2OverCounter << 16) + TIM2->CCR1) / 72;
   //TIM2OverCounter = 0;

   tempTIMIndex++;
   if (tempTIMIndex > 3)
   {
      tempTIMIndex = 0;
   }
   tempTIM[tempTIMIndex] = TIM2->CCR1;
   totalCounter = (tempTIM[0] + tempTIM[1] + tempTIM[2] + tempTIM[3]) >> 2;

   TIM1->ARR = totalCounter << 1;
   TIM1->CCR1 = totalCounter;
   }
}
if (TIM2->SR & TIM_SR_CC2IF)
{
   TIM2->SR &= ~TIM_SR_CC2IF;
   ppState = PPSIN;
   if (ppStateTab[ppState] == ppState2)
   {
   Y10 = !Y10;
   ppState2 = ppState;
   TIM2->CCER ^=  TIM_CCER_CC2P;//切换边沿
   TIM2->SMCR &=  ~TIM_SMCR_TS_1;//切换复位信号
   TIM2->SMCR |=  TIM_SMCR_TS_0;

   //totalCounter = ((TIM2OverCounter << 16) + TIM2->CCR2) / 72;
   //TIM2OverCounter = 0;

   tempTIMIndex++;
   if (tempTIMIndex > 3)
   {
      tempTIMIndex = 0;
   }
   tempTIM[tempTIMIndex] = TIM2->CCR2;
   totalCounter = (tempTIM[0] + tempTIM[1] + tempTIM[2] + tempTIM[3]) >> 2;

   TIM1->ARR = totalCounter << 1;
   TIM1->CCR1 = totalCounter;
   }
}
if (TIM2->SR & TIM_SR_UIF)
{
   TIM2->SR &= ~TIM_SR_UIF;
   TIM2OverCounter++;
}
}

//脉冲输出配置
void PWMTimerInit(void)
{
RCC->APB2ENR|= RCC_APB2ENR_IOPAEN//使能GPIOA的时钟
               +RCC_APB2ENR_TIM1EN;//使能TIM1的时钟
  //端口配置
  GPIOA->CRH&=~(GPIO_CRH_MODE8_0*mode_reset);
GPIOA->CRH|= (GPIO_CRH_MODE8_0*afio_pp_10);//PA8 TIM1CH1 复用10M输出

  //时基模式
  TIM1->CNT = 0;
TIM1->PSC = 0;//
TIM1->ARR = 0xffff;//
TIM1->RCR = 0;
TIM1->CR1 = TIM_CR1_ARPE;//使用预装入，边沿向上计数

  //比较模式
  TIM1->CCR1 = 0x8000;//脉冲低电平宽度，，值加18宽度加1uS
TIM1->CCMR1 = TIM_CCMR1_OC1PE//OC1使能比较寄存器预加载
            +(TIM_CCMR1_OC1M_2+TIM_CCMR1_OC1M_1);//OC1使用PWM模式1

//使能输出
  TIM1->BDTR = TIM_BDTR_MOE;//TIM1主输出使能
  TIM1->CCER = TIM_CCER_CC1E;//OC1输出使能

  //配置中断
  //NVIC_SetPriority(TIM1_UP_IRQn,15);
//NVIC_EnableIRQ(TIM1_UP_IRQn);

//初始化并开启
  TIM1->EGR |= TIM_EGR_UG;//初始化缓冲寄存器
  //TIM1->SR &= ~TIM_SR_UIF;//清更新中断标志
  //TIM1->DIER |= TIM_DIER_UIE;//开启更新中断
  TIM1->CR1 |= TIM_CR1_CEN;//开启TIM1
}