利用STM8的PWM输入捕获测红外码程序

leixiaofeng · 发表于 2015-5-20 20:54:33

实例说明：
1、本实例是利用STM8单片机定时器TIM1的PWM输入捕获模式测量红外遥控码。

2、红外遥控码格式为NEC红外编码。
3、红外接收信号输入接PC1（TIM1输入通道1）。
4、采用外部晶振16M。
5、采用IAR FOR STM8开发环境。
6、程序代码如下：
//--------------------------------------------------------------------
#include "iostm8s105s4.h"

#define uchar unsigned char
#define uint unsigned int

uchar IrRecStep = 0;                            //接收步骤
uchar IrIndex = 0;                               //接收位数
uchar IrRecFlag = 0;                            //接收完标志
uchar IrRecBuff[4];                            //接收缓冲区
uchar IrRecAddr1;                               //红外地址码
uchar IrRecAddr2;
uchar IrRecData1;                               //红外数据码
uchar IrRecData2;
uint IrCycle = 0;                               //红外周期
uint IrHigh = 0;                                  //占空比
const uchar IrCode[8]={0x01,0x02,0x04,0x08,0x10,0x20,0x40,0x80};

//--------引导码低电平范围------------------
#define IrHeadLow_Max    2300          //2300*4 = 9200us
#define IrHeadLow_Min       2100          //2100*4 = 8400us
//--------引导码高电平范围------------------
#define IrHeadHigh_Max    1250          //1250*4 = 5000us
#define IrHeadHigh_Min    1050          //1050*4 = 4200us
//--------数据0的周期范围-------------------
#define IrData00_Max       300          //300*4 = 1200us
#define IrData00_Min       260          //260*4 = 1040us
//--------数据1的周期范围-------------------
#define IrData10_Max       580          //580*4 = 2320us
#define IrData10_Min       540          //540*4 = 2160us
//--------数据0的占空比(高电平)范围---------
#define IrData0_Max       160          //160*4 = 640us
#define IrData0_Min          120          //120*4 = 480us
//--------数据1的占空比(高电平)范围---------
#define IrData1_Max       440          //440*4 = 1760us
#define IrData1_Min          400          //400*4 = 1600us
//----------------------------------------------------------
#define REMOTE_CLK_DIV    63             //63+1=64----16Mh/64=4us
#define REMOTE_ICF_FILTER 0x30

//延时程序
void Delay_ms( uint ms )
{
  uint i,j;
  for( j=0; j<ms; )
{
for( i=0; i<1000; i++ )
{;}
  }
}

//红外接收端口初始化
void Ir_Init(void)
{
  PC_DDR_DDR1 = 0;    //PC1为输入
  PC_CR1_C11 = 1;
  PC_CR2_C21 = 0;
}

//使用TIM1的PWM输入捕获
void Ir_PWM_Init(void)
{
TIM1_PSCRH = 0;
TIM1_PSCRL = REMOTE_CLK_DIV;

  TIM1_CCER1 &= 0xee;//禁止输入捕获1，2
  TIM1_CCMR1 |= (REMOTE_ICF_FILTER + 0x01);// ch1到ti1fp1
  TIM1_CCER1 &= 0xec;//ch1 上升沿触发
  TIM1_CCMR2 |= (REMOTE_ICF_FILTER + 0x02);// ch2选择 ti1fp2上
  TIM1_CCER1 |= 0x20;//ch1 下降沿触发 ic2
  TIM1_SMCR |= 0x54;//选源触发源和触发方式复位
  TIM1_CCER1 |= 0x11;//使能输入捕获1，2
  TIM1_CR1 |= 0x05;
}

//红外接收程序
void Ir_Receive(void)
{
  switch(IrRecStep)
  {
  case 0:
      IrIndex = 0;
      if ((TIM1_SR1_CC1IF == 1)&&(TIM1_SR1_CC2IF == 1))
      {
         IrHigh = (uint)(TIM1_CCR2H);
         IrHigh = (IrHigh << 8) + TIM1_CCR2L;  //IrHigh占空比
         IrCycle = (uint)(TIM1_CCR1H);
         IrCycle = (IrCycle << 8) + TIM1_CCR1L;  //IrCycle周期
         //是否在引导码低电平范围内
         if (((IrCycle - IrHigh) < IrHeadLow_Max)&&((IrCycle - IrHigh) > IrHeadLow_Min))
         {
            IrRecStep = 1;
            TIM1_SR1_CC1IF = 0;
            TIM1_SR1_CC2IF = 0;
            TIM1_SR2_CC1OF = 0;
            TIM1_SR2_CC2OF = 0;
            TIM1_SR1_UIF = 0;

            IrRecBuff[0] = 0;
            IrRecBuff[1] = 0;
            IrRecBuff[2] = 0;
            IrRecBuff[3] = 0;
         }
      }
      break;
  case 1:
      if ((TIM1_SR2_CC1OF==1) || (TIM1_SR2_CC2OF==1) || (TIM1_SR1_UIF==1))
      {
         IrRecStep = 0;
      }
      else
      {
         if ((TIM1_SR1_CC1IF == 1)&&(TIM1_SR1_CC2IF == 1))
         {
            IrHigh = (uint)(TIM1_CCR2H);
            IrHigh = (IrHigh << 8) + TIM1_CCR2L;
            IrCycle = (uint)(TIM1_CCR1H);
            IrCycle = (IrCycle << 8) + TIM1_CCR1L;
            //是否在引导码高电平范围内
            if ((IrHigh < IrHeadHigh_Max)&&(IrHigh > IrHeadHigh_Min))
            {
            IrRecStep = 2;
            }
         }
      }
      break;
  case 2:
      if ((TIM1_SR2_CC1OF==1) || (TIM1_SR2_CC2OF==1) || (TIM1_SR1_UIF==1))
      {
         IrRecStep = 0;
      }
      else
      {
         if ((TIM1_SR1_CC1IF == 1)&&(TIM1_SR1_CC2IF == 1))
         {
            IrHigh = (uint)(TIM1_CCR2H);
            IrHigh = (IrHigh << 8) + TIM1_CCR2L;
            IrCycle = (uint)(TIM1_CCR1H);
            IrCycle = (IrCycle << 8) + TIM1_CCR1L;
            //周期是否在数据0范围内
            if ((IrCycle > IrData00_Min)&&(IrCycle < IrData00_Max))
            {
            //高电平是否在数据0范围内
            if ((IrHigh > IrData0_Min)&&(IrHigh < IrData0_Max))
            {
               IrIndex++;
            }
            else
            {
               IrRecStep = 0;
            }
            }
            //周期是否在数据1范围内
            else if ((IrCycle > IrData10_Min)&&(IrCycle < IrData10_Max))
            {
            //高电平是否在数据1范围内
            if ((IrHigh > IrData1_Min)&&(IrHigh < IrData1_Max))
            {
               IrRecBuff[IrIndex >> 3] |= IrCode[IrIndex & 0x07];
               IrIndex++;
            }
            else
            {
               IrRecStep = 0;
            }
            }
            else
            {
            IrRecStep = 0;
            }
            if(IrIndex >= 32)
            {
            IrRecStep = 0;
            IrRecFlag = 1;
            }
         }
      }
      break;
  }
}

//时钟初始化
void CLK_Init(void)
{
  CLK_ECKR=0x03;//外部时钟寄存器外部时钟准备就绪，外部时钟开
  CLK_SWCR=0x02;//切换控制寄存器使能切换机制
  CLK_SWR=0xB4;//主时钟切换寄存器选择HSE为主时钟源*/

while (!(CLK_SWCR & 0x08));
CLK_CSSR=0x01;//时钟安全系统寄存器
}

//初始化
void Devices_Init(void)
{
  Delay_ms(200);
  CLK_Init();
  Ir_Init();
  Ir_PWM_Init();

}

//主程序
void main( void )
{
  Devices_Init();
  while(1)
  {
Ir_Receive();
if(IrRecFlag == 1)
{
   IrRecAddr1 = IrRecBuff[0];
   IrRecAddr2 = IrRecBuff[1];
   IrRecData1 = IrRecBuff[2];
   IrRecData2 = IrRecBuff[3];
   IrRecFlag = 0;
}
  }
}