irm.c

基于Mini51板的数字示波器设计

#include "osc.h"
#include "irm.h"
#include "number.h"
#include "common.h"

unsigned char irm_code;//红外解码键值返回全局变量
bit  flag  ;// 上一位编码位


void extern2_init(void)
{
	EA = 1;
	IT2 = 1;//下降沿中断
	EX2 = 1;
}

static unsigned char check_bit(unsigned char bit_num)
{
    //最大检测7位    
	unsigned char irm_code0 = 0;
	unsigned char i ;
	unsigned int  count ;
	#define  ERROR	0x10;
	for(i=0;i<bit_num;i++)
	 {
	    count = 0 ;
		irm_code0 = irm_code0<<1 ;
	    if(flag)
		{
		   while(IRM_DQ)if(count++>10000) return ERROR;
		   if(count>150)
		   {
		      flag = 0  ;//  结束码为 10			  		  
		   }
		   else
		   {
		      flag = 1  ;//  结束码为 01
			  irm_code0 |= 0x01;
			  while(!IRM_DQ)if(count++>10000) return ERROR;
		   }
		}
		else   //  结束码为 10
		{
		   while(!IRM_DQ)if(count++>10000) return ERROR;
		   if(count>150)
		   {
		      flag = 1  ;//  结束码为 01
			  irm_code0 |= 0x01;
		   }
		   else
		   {
		      flag = 0  ;//  结束码为 10
			  while(IRM_DQ)if(count++>10000) return ERROR;			  
		   }
		}  
	  }       
	  return irm_code0  ;  //解码成功 ！！
}					  


//STC单片机特有的外部中断INT2实现红外解码
//解码结果由数据缓冲区返回
void IRMint(void) interrupt 6
{		
	unsigned int  count;
	unsigned char temp_code[2];
	
	EA = 0;/*解码过程禁止其它中断发生*/
    IRM_DQ = 1 ;
	/*跳过1.5bit 起始码*/	 
	{
	 count = 0;
	 while(!IRM_DQ)if(count++>1000) goto return_main;
	 count = 0;
	 while(IRM_DQ)if(count++>1000) goto return_main;
	}
	/*跳过1bit控制码和5bit用户码*/	
    {
	 flag = 0 ;  //起始码以10结束
	 temp_code[0] = check_bit(6);	 
	} 
	/*数据码*/
	 temp_code[1] = check_bit(6);	 
	irm_code = temp_code[1] ; //返回键值
	IE2 = 0 ;
	EX2 = 0;
	return_main:	
	EA = 1;	
}


/*按键扫描*/
void key_scan(void)
{	
	unsigned int code timeH [] = {111,254,253,248,241,183};//{50,5000,2500,1000,500,100};
	unsigned int code timeL [] = {255,143, 30,204,153,255};//{50,5000,2500,1000,500,100};

	if(irm_code!=0) {
		switch (irm_code)
		{
			case 30: acdc_flag ^= 0x01;	break;	
			case 31: run_flag  ^= 0x01;	break;	
			case 34: if(pointxA > 0      ) 			pointxA--; break;	
			case 35: if(pointxA < WIDTH-2) 			pointxA++; break;	
			case 42: if(pointxB > 0      ) 			pointxB--; break;	
			case 43: if(pointxB < WIDTH-2) 			pointxB++; break;	
			case 45: if(pointyA > ZEROY-HEIGHT+1)	pointyA--; break;	
			case 44: if(pointyA < ZEROY-2       )	pointyA++; break;
			case 47: if(pointyB > ZEROY-HEIGHT+1) 	pointyB--; break;	
			case 46: if(pointyB < ZEROY-2       ) 	pointyB++; break;
			case 48: if(val_tdiv > 0) val_tdiv--; break;	
			case 49: if(val_tdiv < 4) val_tdiv++; break;
			case 54: if(val_vdiv > 0) val_vdiv--; break;
			case 58: if(val_vdiv < 5) val_vdiv++; break;
			case 55: if(movx > -(WIDTH/2-1)) movx--; break;
			case 56: if(movx <  (WIDTH/2-1)) movx++; break;
			case 63: if(movy > -(HEIGHT/2)) movy--; break;
			case 57: if(movy <  (HEIGHT/2)) movy++; break;
			default: break;
		}
		
		RCAP2H = timeH[val_tdiv];
		RCAP2L = timeL[val_tdiv];		
  
		irm_code=0;
		BEEP_ON();
		disp_vdiv();
	   	disp_ypoint(); 
		delay_ms(200);
		BEEP_OFF();
		delay(10000);
		EX2 = 1;		
	}
}