新人求问

#include <reg52.h>
#include <intrins.h>
#include <string.h>
#include <stdio.h>
#define uint unsigned int
#define uchar unsigned char
sbit red_1=P1^0;
sbit red_2=P1^1;
sbit red_3=P1^2;
sbit red_4=P1^3;
sbit red_5=P1^4;
sbit led_1=P0^7;
#define MAXCHAR 81
uchar aa[MAXCHAR];
code uchar ATE0[]="ATE0\r\n";
code uchar CREG_CMD[]="AT+CREG?\r\n";
code uchar SMS_send[]="AT+CMGS=18\r\n";
code uchar ATCN[]="AT+CNMI=2,1\r\n";
code uchar CMGF0[]="AT+CMGF=0\r\n";
code uchar CMGF1[]="AT+CMGF=1\r\n";
code uchar CMGR[12]="AT+CMGR=1\r\n";
code uchar CMGD[12]="AT+CMGD=1\r\n";
#define CALL_YOU_TELNUMBER "ATD18113974162;\r\n"
#define SEND_MESSA_TO_YOUR "at+cmgs=\"18113974162\"\r\n"
#define SEND_MESSA_CONTENT "warning"
uchar a,j=0,flag=0;
int g_timeout=0;
void delay(uint ms)
{
uchar i;
while(ms--)
{
for(i=0;i<120;i++);
}
}
Print_Char(uchar ch)
{
SBUF=ch;
while(TI!=1);
TI=0;
}
Print_Str(uchar *str)
{
while(*str!='\0')
{
Print_Char(*str);
delay(2);
str++;
}
}
Ini_UART(void)
{
SCON = 0x50 ;
TMOD |= 0x20 ;
PCON |= 0x80 ;
TH1 = 0xFA ;
TL1=0xFA;
IE |= 0x90 ;
TR1 = 1 ;
TI=1;
ES=1;
EA=1;
EX0=0;
IT0=0;
}
void clearBuff(void)
{
for(j=0;j<MAXCHAR;j++)
{
aa[j]=0x00;
}
j=0;
}
void led(int i)
{
P0 |= i;
delay(20);
P0 &= ~i;
delay(20);
P0 |= i;
delay(20);
P0 &= ~i;
}
int Hand()
{
delay(10);
if(strstr(aa,"OK")!=NULL)
{
g_timeout=0;
return 1;
}
if(g_timeout>50)
{
g_timeout=0;
return -1;
}
g_timeout++;
return 0;
}
void AT(void)
{
clearBuff();
Print_Str(ATE0);
delay(50);
while(strstr(aa,"OK")==NULL)
{
delay(50);
led(0x01);
clearBuff();
Print_Str(ATE0);
}
led(0x02);
Print_Str(ATCN);
delay(50);
while(1)
{
clearBuff();
Print_Str(CREG_CMD);
delay(50);
if(((aa[9]=='0')&&(aa[11]=='1'))||((aa[9]=='0')&&(aa[11]=='5')))
{
clearBuff();
led(0x08);
break;
}
else
{
clearBuff();
led(0x04);
delay(50);
}
}
}
void send_english()
{
P0=0XFF;
clearBuff();
Print_Str(CMGF1);
delay(100);
led(0x01);
Print_Str(SEND_MESSA_TO_YOUR);
delay(300);
led(0x02);
Print_Str(SEND_MESSA_CONTENT);
delay(10);
Print_Char(0x1A);
delay(10);
led(0x04);
clearBuff();
delay(3000);
delay(3000);
}
void send_call()
{
clearBuff();
delay(100);
Print_Str(CALL_YOU_TELNUMBER);
clearBuff();
delay(3000);
delay(3000);
}
void main()
{
Ini_UART();
AT();
delay(10);
clearBuff();
Print_Str(CMGD);
delay(50);
while(Hand()==0);
clearBuff();
Print_Str(CMGF1);
delay(30);
Print_Str(ATCN);
delay(30);
send_english();
while(1)
{
if(strstr(aa,"+CMTI")!=NULL)
{
clearBuff();
Print_Str(CMGF1);
delay(50);
while(Hand()==0);
clearBuff();
Print_Str(CMGR);
delay(100);
if(strstr(aa,"1")!=NULL)
{
EX0=1;
}
else if(strstr(aa,"2")!=NULL)
{
EX0=0;
}
clearBuff();
Print_Str(CMGD);
delay(50);
while(Hand()==0);
clearBuff();
}
}
}
void ser() interrupt 4
{
if(RI==1)
{ aa[j]=SBUF;
RI=0;
j++;
}
}
主函数里while之前都能很快运行，到while了，给信号几乎要3分钟才会有响应，这是怎么回事啊