51掉電模式下，紅外頭，INT1外部中斷喚醒，需要遙控器按2次的問(wèn)題。

ID:70095 · 發(fā)表于 2014-12-7 17:08

單片機(jī)用的是STC12C5A60S2，晶振11.0592MHz。

進(jìn)入掉電模式的流程圖：

故障表現(xiàn)：進(jìn)入wile循環(huán)后，已經(jīng)進(jìn)入掉電模式后，液晶屏?xí)欢〞r(shí)自動(dòng)的出現(xiàn)輸出的字符"D"，或1分鐘，或5分鐘，或10分鐘(根據(jù)代碼會(huì)出現(xiàn)字符“D”是表示外部中斷喚醒，進(jìn)入失��？)。紅外遙控器按一次只會(huì)輸出一個(gè)“D”，無(wú)法完成整個(gè)解碼過(guò)程，連續(xù)按2次解碼正常。請(qǐng)問(wèn)這是什么問(wèn)題（下面有完整的電路圖，源代碼）？謝謝！

電路圖：點(diǎn)擊可放大

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C源代碼：

/*STC12C5A60S2 11.0592MHz*/
#include <reg52.h>
#include <intrins.h>
#define uchar unsigned char
#define uint unsigned int

sbit rs=P3^6; //1602數(shù)據(jù)/命令
sbit e=P3^7; //1602使能控制
sbit dyled=P0^0; //電源指示燈及用作測(cè)試
sbit j=P2^0; //繼電器
sbit IR_INPUT = P3^3; //1838紅外接收引腳

bit irflag = 0; //紅外接收標(biāo)志，收到一幀正確數(shù)據(jù)后置1

unsigned char ircode[4]; //紅外代碼接收
unsigned char disp[11];
unsigned char code Tab[16]="0123456789ABCDEF";

void InitInfrared()
{
IR_INPUT = 1;
TMOD &= 0X0F;
TMOD |= 0x10;
TR1 = 0;
ET1 = 0;
IT1 = 1;
EX1 = 1;
}
unsigned int GetHighTime()
{
TH1 = 0;
TL1 = 0;
TR1 = 1;
while(IR_INPUT)
{
      if(TH1 > 0x40)
      {
         break;
      }
}
TR1 = 0;

return(TH1 * 256 + TL1);
}

unsigned int GetLowTime()
{
TH1 = 0;
TL1 = 0;
TR1 = 1;
while(!IR_INPUT)
{
      if(TH1 > 0x40)
      {
         break;
      }
}
TR1 = 0;

return(TH1 * 256 + TL1);
}
void EXINT1_ISR() interrupt 2 //TNT1中斷紅外一體接收頭
{
unsigned char i, j;
unsigned int time;
unsigned char byt;

time = GetLowTime();
if((time <7833) || (time > 8755))
{
      IE1 = 0;
      return;
}

time = GetHighTime();
if((time<3686) || (time > 4608))
{
      IE1 = 0;
      return;
}

dyled=0; //遙控器按下按鍵，掉電喚醒后，程序到這里終止(喚醒后的一瞬間無(wú)晶起振或是起振不及時(shí)導(dǎo)致？)

for(i=0; i<4; i++)
{
      for(j=0; j<8; j++)
      {
         time = GetLowTime();
         if((time<313) ||(time >718))
         {
            IE1 = 0;
            return;
         }
         time = GetHighTime();
         if((time>313) && (time <718))
         {
            byt >>= 1;
         }
         else if((time>1345) && (time<1751))
         {
            byt >>= 1;
            byt |= 0x80;
         }
         else
         {
            IE1 = 0;
            return;
         }
      }
      ircode[ i] = byt;
}
irflag = 1;
IE1 = 0;
}

void delay_50us(uint t) //延時(shí)
{
uint j;
for(;t>0;t--)
for(j=6245;j>0;j--);
}

void write_com(uchar com) //液晶屏寫(xiě)指令
{
e=0;
rs=0;
P1=com;
delay_50us(10);
e=1;
delay_50us(20);
e=0;
}

void write_data(uchar dat) //液晶屏寫(xiě)數(shù)據(jù)
{
e=0;
rs=1;
P1=dat;
delay_50us(10);
e=1;
delay_50us(20);
e=0;
}

void init() //液晶屏初始化
{
delay_50us(300);
write_com(0x38);
delay_50us(100);
write_com(0x38);
delay_50us(100);
write_com(0x38);
delay_50us(100);
write_com(0x38);
write_com(0x38);
write_com(0x08);
write_com(0x01);
write_com(0x06);
write_com(0x0c);
}

void main(void)
{
EA = 1; //開(kāi)總中斷
InitInfrared(); //初始化紅外功能
init(); //液晶屏初始化
while (1)
{
      if (irflag)  //接收到紅外數(shù)據(jù)時(shí)刷新顯示
      {
         irflag = 0;

         write_com(0x01); //清屏
         delay_50us(10);

         write_com(0x80); //定位寫(xiě)出位置

         disp[0]=Tab[ircode[0]/16]; //二進(jìn)制到十六進(jìn)制賦值給紅外碼數(shù)組
         disp[1]=Tab[ircode[0]%16];
         disp[2]='-';
         disp[3]=Tab[ircode[1]/16];
         disp[4]=Tab[ircode[1]%16];
         disp[5]='-';
         disp[6]=Tab[ircode[2]/16];
         disp[7]=Tab[ircode[2]%16];
         disp[8]='-';
         disp[9]=Tab[ircode[3]/16];
         disp[10]=Tab[ircode[3]%16];

         write_data(disp[0]); //disp紅外碼數(shù)組，輸出到1602液晶屏
         delay_50us(5);
         write_data(disp[1]);
         delay_50us(5);
         write_data(disp[2]);
         delay_50us(5);
         write_data(disp[3]);
         delay_50us(5);
         write_data(disp[4]);
         delay_50us(5);
         write_data(disp[5]);
         delay_50us(5);
         write_data(disp[6]);
         delay_50us(5);
         write_data(disp[7]);
         delay_50us(5);
         write_data(disp[8]);
         delay_50us(5);
         write_data(disp[9]);
         delay_50us(5);
         write_data(disp[10]);
         delay_50us(5);

         write_com(0x80+0x40);
         delay_50us(5);
         write_data(disp[4]);
         delay_50us(5);

         if((disp[0] == '4') && (disp[4] == 'C') && (disp[6] == '1') && (disp[7] == '4'))
         {
            dyled=~dyled;
            j=~j; //繼電器響應(yīng)紅外按鍵信號(hào)
         }
      }
      dyled=1;
      PCON = 0X02; //掉電模式
      _nop_();_nop_();_nop_();_nop_();_nop_();
      _nop_();_nop_();_nop_();_nop_();_nop_();
      _nop_();_nop_();_nop_();_nop_();_nop_();

      delay_50us(5);
      write_data(' ');
      delay_50us(5);
      write_data('D'); //已經(jīng)進(jìn)入掉電模式后，液晶屏?xí)欢〞r(shí)出現(xiàn)輸出的字符"D"，或5秒或7秒或20秒(進(jìn)入失��？)
      dyled=1;
      //delay_50us(50);
}
}

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STC12C5A60S2官方的掉電模式代碼：

#include "reg51.h"
#include "intrins.h"

//External interrupt0 service routine
void exint1() interrupt 2          //(location at 0013H)
{
}

void main()
{
IT1 = 1;                      //set INT1 int type (1:Falling 0:Low level)
EX1 = 1;                      //enable INT1 interrupt
EA = 1;                      //open global interrupt switch

while (1)
{
      INT1 = 1;                //ready read INT1 port
      while (!INT1);             //check INT1
      _nop_();
      _nop_();
      PCON = 0x02;             //MCU power down
      _nop_();
      _nop_();
      P1++;
}
}