单片机学习笔记之4——编码器转速的获取

最近的学校电赛初赛有一个自控小车的题目，其中的编码器读取转速还是费了我一些时间学习的，这里把编码器的初始化等代码以及main函数的测试代码加了一些注释放出来作为参考。

  #include "encoder.h"
 
void encoder_left_Init(void)
{
    GPIO_InitTypeDef         GPIO_InitStructure; 
    TIM_TimeBaseInitTypeDef  TIM_TimeBaseStructure;
    TIM_ICInitTypeDef        TIM_ICInitStructure;
 
    RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM4,ENABLE);//开启TIM4时钟
    RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOD,ENABLE);//开启GPIOB时钟
  
    GPIO_PinAFConfig(GPIOD,GPIO_PinSource12,GPIO_AF_TIM4);//D12引脚复用
    GPIO_PinAFConfig(GPIOD,GPIO_PinSource13,GPIO_AF_TIM4);//D13引脚服用
 
    GPIO_InitStructure.GPIO_Pin = GPIO_Pin_12|GPIO_Pin_13; //GPIOD12,GPIOD13
    GPIO_InitStructure.GPIO_Mode  = GPIO_Mode_AF;
    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_100MHz;
    GPIO_InitStructure.GPIO_OType = GPIO_OType_OD;
    GPIO_InitStructure.GPIO_PuPd  = GPIO_PuPd_UP ;
    GPIO_Init(GPIOD,&GPIO_InitStructure); 
 
 
 
    TIM_TimeBaseStructure.TIM_Period = 65535; //设置下一个更新事件装入活动的自动重装载寄存器周期的值
    TIM_TimeBaseStructure.TIM_Prescaler = 0; //设置用来作为TIMx时钟频率除数的预分频值  不分频
    TIM_TimeBaseStructure.TIM_ClockDivision = 0; //设置时钟分割:TDTS = Tck_tim
    TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;  //TIM向上计数模式
    TIM_TimeBaseInit(TIM4, &TIM_TimeBaseStructure); 
 
   //设置定时器为编码器模式   IT1  IT2为上升沿和下降沿都计数四倍频
    TIM_EncoderInterfaceConfig(TIM4, TIM_EncoderMode_TI12,TIM_ICPolarity_BothEdge,TIM_ICPolarity_BothEdge);
    TIM_ICStructInit(&TIM_ICInitStructure);
    TIM_ICInitStructure.TIM_ICFilter = 0;  //输入滤波器
    TIM_ICInit(TIM4, &TIM_ICInitStructure);
    TIM_ClearFlag(TIM4, TIM_FLAG_Update);  //清楚所有标志位
    TIM_ITConfig(TIM4, TIM_IT_Update, ENABLE); //允许中断更新
    TIM4->CNT = 0;
    TIM_Cmd(TIM4, ENABLE);  //使能TIM4
}

 
void encoder_right_Init(void)
{
    GPIO_InitTypeDef         GPIO_InitStructure; 
    TIM_TimeBaseInitTypeDef  TIM_TimeBaseStructure;
    TIM_ICInitTypeDef        TIM_ICInitStructure;
 
    RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM3,ENABLE);//开启TIM3时钟
    RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOC,ENABLE);//开启GPIOC时钟
  
    GPIO_PinAFConfig(GPIOC,GPIO_PinSource6,GPIO_AF_TIM4);//PC6引脚复用
    GPIO_PinAFConfig(GPIOC,GPIO_PinSource7,GPIO_AF_TIM4);//PC7引脚服用
 
    GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6|GPIO_Pin_7; //GPIOC6,GPIOC7
    GPIO_InitStructure.GPIO_Mode  = GPIO_Mode_AF;
    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_100MHz;
    GPIO_InitStructure.GPIO_OType = GPIO_OType_OD;
    GPIO_InitStructure.GPIO_PuPd  = GPIO_PuPd_UP ;
    GPIO_Init(GPIOC,&GPIO_InitStructure); 
 
 
 
    TIM_TimeBaseStructure.TIM_Period = 65535; //设置下一个更新事件装入活动的自动重装载寄存器周期的值
    TIM_TimeBaseStructure.TIM_Prescaler = 0; //设置用来作为TIMx时钟频率除数的预分频值  不分频
    TIM_TimeBaseStructure.TIM_ClockDivision = 0; //设置时钟分割:TDTS = Tck_tim
    TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;  //TIM向上计数模式
    TIM_TimeBaseInit(TIM3, &TIM_TimeBaseStructure); 
 
   //设置定时器为编码器模式   IT1  IT2为上升沿和下降沿都计数四倍频
    TIM_EncoderInterfaceConfig(TIM3, TIM_EncoderMode_TI12,TIM_ICPolarity_BothEdge,TIM_ICPolarity_BothEdge);
    TIM_ICStructInit(&TIM_ICInitStructure);
    TIM_ICInitStructure.TIM_ICFilter = 0;  //输入滤波器
    TIM_ICInit(TIM3, &TIM_ICInitStructure);
    TIM_ClearFlag(TIM3, TIM_FLAG_Update);  //清楚所有标志位
    TIM_ITConfig(TIM3, TIM_IT_Update, ENABLE); //允许中断更新
    TIM4->CNT = 0;
    TIM_Cmd(TIM3, ENABLE);  //使能TIM3
}



void TIM4_IRQHandler(void)
{                         
  if(TIM4->SR&0X0001)//溢出中断
  {                                 
  }          
  TIM4->SR&=~(1<<0);//清除中断标志位       
}

void TIM3_IRQHandler(void)
{                         
  if(TIM3->SR&0X0001)//溢出中断
  {                                 
  }          
  TIM3->SR&=~(1<<0);//清除中断标志位       
}

//参数说明：左边：3，右边：4
int Read_Encoder(u8 TIMX)
{
    int Encoder_TIM;    
   switch(TIMX)
     {
        case 2:  Encoder_TIM= (short)TIM2 -> CNT;  TIM2 -> CNT=0;break;
        case 3:  Encoder_TIM= (short)TIM3 -> CNT;  TIM3 -> CNT=0;break;    
        case 4:  Encoder_TIM= (short)TIM4 -> CNT;  TIM4 -> CNT=0;break;    
        default:  Encoder_TIM=0;
     }
        return Encoder_TIM;
}

#include "sys.h"
#include "usart.h"
#include "delay.h"
#include "led.h"
#include "encoder.h"
#include "lcd.h"

int pwm(int percentage,GPIO_TypeDef* GPIOx, uint16_t GPIO_Pin);


int main(void)
{
	int encoder_left=0;//编码器数值存储
	int encoder_right=0;//编码器数值存储
	char printstr[30]={0};//屏幕字符串输出暂存
	NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2);//设定中断分组
	delay_init(168);//延迟初始化
	uart_init(115200);//串口初始化
	LCD_Init();  //LCD屏幕初始化
	POINT_COLOR=BLUE;  //设定画笔颜色为蓝色
	LCD_Clear(WHITE);//屏幕背景设为蓝色
	encoder_left_Init();//左侧编码器初始化
	encoder_right_Init();//右侧编码器初始化
	while(1)
	{
		encoder_left=Read_Encoder(3);//读取左侧编码器数值
		encoder_right=Read_Encoder(4);//读取右侧编码器数值
		sprintf(printstr,"Left encoder value is:%d",encoder_left);//生成输出字符串
		LCD_ShowString(30,50,200,16,16,printstr);//屏幕数据显示
		sprintf(printstr,"Right encoder value is:%d",encoder_right);//同上
		LCD_ShowString(30,70,200,16,16,printstr);
		delay_ms(100);//延时0.1秒
		LCD_Clear(WHITE);//清屏
	}
}