MSP430(F149)学习笔记——红外接收

用MSP430（F149）做红外接收比发送更为简单，我采用的红外传感器是HS0038B，这个原件在接收到38K红外时输出低电平，否则输出高电平，因此，我们就可以从这点开始编写程序了，由于HS0038B的电路图很多，我这里就不贴出来了，下面是具体的代码：

 

#include <msp430x14x.h>

#include "delay.h"



static unsigned short addr = 0x00;

static unsigned char ir_rx_buf[256];

static unsigned char ir_rx_w_offset = 0;

static unsigned char ir_rx_r_offset = 0;



void ir_tx_open(){

  P2DIR |= BIT2 | BIT3;//P2.2, P2.3输出

  P2SEL |= BIT3; //P2.2:IO P2.3:TA0

  P2SEL &= ~BIT2; //

  P2OUT &= ~(BIT2 | BIT3);

  

  //38K->P2.3

  CCR0 = (int)(26.3*8 + 0.5);

  CCTL1 = OUTMOD_6;

  CCR1 = (int)(13.15*8 + 0.5);



  TACTL = TASSEL_2 + MC_1;

}



void ir_set_addr(unsigned char addr){

  addr = (unsigned char)(0xff&addr);

}



static void ir_start(){

  P2OUT |= BIT2;

  delay_us(9000);

  

  P2OUT &= ~BIT2;

  delay_us(4500);

}



static void ir_next(){

  P2OUT |= BIT2;

  delay_us(9000);

  

  P2OUT &= ~BIT2;

  delay_us(2250);

}



static void ir_send_byte(unsigned char c){

  unsigned char i;

  

  for(i = 0; i != 8; ++i){

    P2OUT |= BIT2;

    delay_us(560);

    

    P2OUT &= ~BIT2;

    if(c&0x01){

      delay_us(1685);

    }

    else{

      delay_us(565);

    }

    

    c >>= 1;

  }

}



static void ir_end(){

  P2OUT |= BIT2;

  delay_us(300);

  P2OUT &= ~BIT2;

}



void ir_put_char(unsigned char c){

  ir_start();

  ir_send_byte(addr);

  ir_send_byte(~addr);

  ir_send_byte(c);

  ir_send_byte(~c);

  ir_end();

}



void ir_put_string(char* str){

  if(*str != '\0')

    ir_start();

  else

    return;

  while(1){

    ir_send_byte(addr);

    ir_send_byte(~addr);

    ir_send_byte(*str);

    ir_send_byte(~(*str));

    

    ++str;

    

    if(*str != '\0'){

      ir_next();

    }

    else{

      ir_end();

    }

  }

}



void ir_put_array(unsigned char* array, unsigned int length){

  unsigned int i;

  

  ir_start();

  

  for(i = 0; i != length; ++i){

    ir_send_byte(addr);

    ir_send_byte(~addr);

    ir_send_byte(array[i]);

    ir_send_byte(array[i]);

    

    if(i < length-1){

      ir_next();

    }

    else{

      ir_end();

    }

  }

}



void ir_tx_close(){

  P2SEL &- ~BIT3;

  P2DIR |= BIT3;

  P2OUT &= ~BIT3;

  TACTL = TACLR;

}



void ir_rx_open(){

  P2SEL &= ~BIT0; //I/O

  P2DIR &= ~BIT0; //Input

  P2IES |= BIT0;  //High->Low

  P2IE  |= BIT0;  //Enable interrupt

}



void ir_rx_close(){

  P2IE  &= ~BIT0;  //Disable interrupt

}



unsigned char ir_get(){

  while(ir_rx_r_offset == ir_rx_w_offset);

  return ir_rx_buf[ir_rx_r_offset++];

}



#pragma vector=PORT2_VECTOR

__interrupt void port2_handler(){

  static unsigned char ir_code[4];

  unsigned char i, j;

  unsigned short time;

  

  if(P2IFG&BIT0){

    P2IE &= ~BIT0;

    P2IFG &= ~BIT0;

    _EINT();

    

    time_start(9500);

    while(!time_out() && !(P2IN&BIT0));

    time = time_end();

    if(!time_out() && time > 8500){

      time_start(5000);

      while(!time_out() && (P2IN&BIT0));

      time = time_end();

      if(!time_out() && time > 4000){

        for(i = 0; i != 4; ++i){

          for(j = 0; j != 8; ++j){

            while(!(P2IN&BIT0));//等待高电平

            time_start(2000);   //计时高电平

            while(!time_out() && (P2IN&BIT0));

            time = time_end();

            ir_code[i] >>= 1;

            if(!time_out() && time > 1500){

              //uart_put(0x03);

              ir_code[i] |= 0x80;

            }

            else{

              //uart_put(0x04);

              ir_code[i] &= 0x7f;

            }

          }

        }

        

        if(ir_code[0] == addr && (0xff == ir_code[0] + ir_code[1])){

          if(0xff == ir_code[2] + ir_code[3]){

            ir_rx_buf[ir_rx_w_offset++] = ir_code[2];

          }

        }

      }

    }

    

    P2IE |= BIT0;;

  }

}

包含整理后的红外发送和接收，放在这里做个记录，有什么疑问欢迎留言讨论。