stm32f10x_encoder.c

ARM_CORTEX-M3应用实例开发详解光盘

/*******************************************************************************
* 文件名          : stm32f10x_encoder.c 
* 功能描述        : 编码器实现程序
*******************************************************************************/
/* 头文件 */
#include "stm32f10x.h"
#include "stm32f10x_encoder.h"
#include "stm32f10x_it.h"
#include "MC_Globals.h"
#include "stm32f10x_MClib.h"


#define COUNTER_RESET       (u16) ((((s32)(ALIGNMENT_ANGLE)*4*ENCODER_PPR/360)\
                                                              -1)/POLE_PAIR_NUM)
#define ICx_FILTER          (u8) 8 // 8<-> 670nsec

#define SPEED_SAMPLING_FREQ (u16)(2000/(SPEED_SAMPLING_TIME+1))

#define TIMx_PRE_EMPTION_PRIORITY 2
#define TIMx_SUB_PRIORITY 0

#define SPEED_SAMPLING_TIME   PID_SPEED_SAMPLING_TIME

// To avoid obvious initialization errors...
#if  ( (defined(TIMER2_HANDLES_ENCODER) && defined(TIMER3_HANDLES_ENCODER)) \
    || (defined(TIMER2_HANDLES_ENCODER) && defined(TIMER4_HANDLES_ENCODER)) \
    || (defined(TIMER3_HANDLES_ENCODER) && defined(TIMER4_HANDLES_ENCODER)))
  #error "Invalid encoder setup: 2 timers selected"
#endif

#ifdef ENCODER

// 编码器未连接提示信息
#ifndef TIMER2_HANDLES_ENCODER
#ifndef TIMER3_HANDLES_ENCODER
#ifndef TIMER4_HANDLES_ENCODER
#warning "Encoder not selected"
#endif
#endif
#endif
#endif  // ENCODER

/* Private functions ---------------------------------------------------------*/
s16 ENC_Calc_Rot_Speed(void);

/* Private variables ---------------------------------------------------------*/
static s16 hPrevious_angle, hSpeed_Buffer[SPEED_BUFFER_SIZE], hRot_Speed;
static u8 bSpeed_Buffer_Index = 0;
static volatile u16 hEncoder_Timer_Overflow;   //该变量指示UPDATE中断发生的个数，也就是说
											   //ENC每转一圈，CPU得到 4* PPR个脉冲，中断发生一次
											   //该变量+1.
static bool bIs_First_Measurement = TRUE;
static bool bError_Speed_Measurement = FALSE;

/*******************************************************************************
* 函数名  : ENC_Init
* 功能描述    : 通用定时器设置->编码器速度/位置感应.
* 输入         : 无
* 输出         : 无
* 返回         : 无
*******************************************************************************/

void ENC_Init(void)
{
  TIM_TimeBaseInitTypeDef  TIM_TimeBaseStructure;
  TIM_ICInitTypeDef TIM_ICInitStructure;
  
#if defined(TIMER2_HANDLES_ENCODER)   // 连接到TIM2, 4X模式
    
  GPIO_InitTypeDef GPIO_InitStructure;
  NVIC_InitTypeDef NVIC_InitStructure;
    
  /* TIM2时钟使能 */
  RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2, ENABLE);
  /* GPIOA时钟使能 */
  RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);
  
  GPIO_StructInit(&GPIO_InitStructure);
  /* 配置PA00,01作为编码器输入*/
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0 | GPIO_Pin_1 | GPIO_Pin_2;
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;
  GPIO_Init(GPIOA, &GPIO_InitStructure);
  
  /* 使能TIM2更新中断*/
  NVIC_InitStructure.NVIC_IRQChannel = TIM2_IRQn;
  NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = TIMx_PRE_EMPTION_PRIORITY;
  NVIC_InitStructure.NVIC_IRQChannelSubPriority = TIMx_SUB_PRIORITY;
  NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
  NVIC_Init(&NVIC_InitStructure);

#elif defined(TIMER3_HANDLES_ENCODER) // 编码器连接TIM3, 4X 模式
  GPIO_InitTypeDef GPIO_InitStructure;
  NVIC_InitTypeDef NVIC_InitStructure;
  
  /* 使能TIM3时钟 */
  RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM3, ENABLE);
  /* 使能GPIOA时钟*/
  RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);
  
  GPIO_StructInit(&GPIO_InitStructure);
  /* 配置PA06,07作为编码器输入 */
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6 | GPIO_Pin_7;
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;
  GPIO_Init(GPIOA, &GPIO_InitStructure);
  
  /* 使能TIM3 更新中断 */
  NVIC_InitStructure.NVIC_IRQChannel = TIM3_IRQn;
  NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = TIMx_PRE_EMPTION_PRIORITY;
  NVIC_InitStructure.NVIC_IRQChannelSubPriority = TIMx_SUB_PRIORITY;
  NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
  NVIC_Init(&NVIC_InitStructure);

#elif defined(TIMER4_HANDLES_ENCODER) // 编码器连接到TIM4, 4X 模式
  GPIO_InitTypeDef GPIO_InitStructure;
  NVIC_InitTypeDef NVIC_InitStructure;
  
  /* 使能TIM4 */
  RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM4, ENABLE);
  /* 使能GPIOA*/
  RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB, ENABLE);
  
  GPIO_StructInit(&GPIO_InitStructure);
  /* 配置PB06,07编码器输入 */
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6 | GPIO_Pin_7;
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;
  GPIO_Init(GPIOB, &GPIO_InitStructure);
  
  /* 使能TIM4 更新中断 */
  NVIC_InitStructure.NVIC_IRQChannel = TIM4_IRQn;
  NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = TIMx_PRE_EMPTION_PRIORITY;
  NVIC_InitStructure.NVIC_IRQChannelSubPriority = TIMx_SUB_PRIORITY;
  NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
  NVIC_Init(&NVIC_InitStructure);
#endif

  /* 定时器配置成编码模式 */
  TIM_DeInit(ENCODER_TIMER);
  TIM_TimeBaseStructInit(&TIM_TimeBaseStructure);
  /* No prescaling ,可以改变编码器计数对于脉冲输入个数的倍数*/
  TIM_TimeBaseStructure.TIM_Prescaler = 0x0;  
  TIM_TimeBaseStructure.TIM_Period = (4*ENCODER_PPR)-1;  
  TIM_TimeBaseStructure.TIM_ClockDivision = TIM_CKD_DIV1;
  TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;   
  TIM_TimeBaseInit(ENCODER_TIMER, &TIM_TimeBaseStructure);
 
  TIM_EncoderInterfaceConfig(ENCODER_TIMER, TIM_EncoderMode_TI12, 
                             TIM_ICPolarity_Rising, TIM_ICPolarity_Rising);
  TIM_ICStructInit(&TIM_ICInitStructure);
  
  TIM_ICInitStructure.TIM_ICFilter = ICx_FILTER;
  TIM_ICInit(ENCODER_TIMER, &TIM_ICInitStructure);
  
  TIM_ICInitStructure.TIM_Channel = TIM_Channel_2;
  TIM_ICInit(ENCODER_TIMER, &TIM_ICInitStructure);
      
 /*清除所有挂起中断*/
  TIM_ClearFlag(ENCODER_TIMER, TIM_FLAG_Update);
  TIM_ITConfig(ENCODER_TIMER, TIM_IT_Update, ENABLE);
  /*复位计数器*/
  ENCODER_TIMER->CNT = COUNTER_RESET; 
  
  TIM_Cmd(ENCODER_TIMER, ENABLE);
}

/*******************************************************************************
* 函数名  : ENC_Get_Electrical_Angle
* 功能描述    : 返回转子电角度 
* Input       : 无
* 输出        : 无
* 返回        : 转子电角度: 0 -> 0 度, 
*               S16_MAX-> 180 度, 
*               S16_MIN-> -180 度
*******************************************************************************/
s16 ENC_Get_Electrical_Angle(void)
{
  s32 temp;
  
  temp = (s32)(TIM_GetCounter(ENCODER_TIMER)) * (s32)(U32_MAX / (4*ENCODER_PPR));         
  temp *= POLE_PAIR_NUM;  
  return((s16)(temp/65536)); // s16结果值
}

/*******************************************************************************
* 函数名  : ENC_Get_Mechanical_Angle
* 功能描述    : 返回转子机械角度 
* 输入          : 无
* 输出          : 无
* 返回          : 转子机械角度: 0 -> 0 度, 
*               S16_MAX-> 180 度, 
*               S16_MIN-> -180 度
*******************************************************************************/
s16 ENC_Get_Mechanical_Angle(void)
{
  s32 temp;
  
  temp = (s32)(TIM_GetCounter(ENCODER_TIMER)) * (s32)(U32_MAX / (4*ENCODER_PPR)) ;
  return((s16)(temp/65536)); // s16 result
}

/*******************************************************************************
* 函数名  : ENC_ResetEncoder
* 功能描述    : 写编码器计数器值
* 输入          : 无
* 输出          : 无
* 返回          : 无
*******************************************************************************/
void ENC_ResetEncoder(void)
{
  //Reset counter
  TIM2->CNT = COUNTER_RESET;   
}

             
/*******************************************************************************
* 函数名  : ENC_Clear_Speed_Buffer
* 功能描述    : 清速度缓存区  
* 输入          : 无
* 输出          : 无
* 返回          : 无
*******************************************************************************/
void ENC_Clear_Speed_Buffer(void)
{   
  u32 i;

  for (i=0;i<SPEED_BUFFER_SIZE;i++)
  {
    hSpeed_Buffer[i] = 0;
  }
  bIs_First_Measurement = TRUE;
}

/*******************************************************************************
* 函数名  : ENC_Calc_Rot_Speed
* 功能描述    : 返回最后速度测量值 
* 输入          : 无 
* 输出          : s16
* 返回          : 
*******************************************************************************/
s16 ENC_Calc_Rot_Speed(void)
{   
  s32 wDelta_angle;
  u16 hEnc_Timer_Overflow_sample_one, hEnc_Timer_Overflow_sample_two;
  u16 hCurrent_angle_sample_one, hCurrent_angle_sample_two;
  signed long long temp;
  s16 haux;
  
  if (!bIs_First_Measurement)
  {
    // 1st reading of overflow counter    
    hEnc_Timer_Overflow_sample_one = hEncoder_Timer_Overflow;  //马达旋转圈数。
    // 1st reading of encoder timer counter
    hCurrent_angle_sample_one = ENCODER_TIMER->CNT;			 //当前马达位置
    // 2nd reading of overflow counter
    hEnc_Timer_Overflow_sample_two = hEncoder_Timer_Overflow;  
    // 2nd reading of encoder timer counter
    hCurrent_angle_sample_two = ENCODER_TIMER->CNT;      

    // Reset hEncoder_Timer_Overflow and read the counter value for the next
    // measurement
    hEncoder_Timer_Overflow = 0;
    haux = ENCODER_TIMER->CNT;   	  //马达不会转的如此之快，在执行完这个指令后就又转了一圈。？？
    
    if (hEncoder_Timer_Overflow != 0) 
    {
      haux = ENCODER_TIMER->CNT; 
      hEncoder_Timer_Overflow = 0;            
    }
     
    if (hEnc_Timer_Overflow_sample_one != hEnc_Timer_Overflow_sample_two)
    { //Compare sample 1 & 2 and check if an overflow has been generated right 
      //after the reading of encoder timer. If yes, copy sample 2 result in 
      //sample 1 for next process