我用C52写的GSM发送短信息程序有数据发送但没回应？？？？

#include "reg52.h"
#include "string.h"
#include <intrins.h>
#define uchar unsigned char
#define uint unsigned int

uchar RsBuf[24];
uchar FlagRs = 0;

char code Init_Tc35i[] = "^SYSSTART";
char code AT_Tc35i[] = "AT+";           //连机
//char code Bps_Tc35[]="IPR=9600";
uchar code AT_CSCA[]="AT+CSCA=13800200500";
uchar code AT_CMGF[]="AT+CMGF=1";
char code Send_Tc35i[] = "CMGS=";       //发送信息
char code AT_Code[]="OK";
char code SK[]=">";
char code PhonNum[] = "13535058054";
char code Test[] = "test123";
bit fa=0;
//延时t毫秒
void Delay(uchar t)
{
uint i;
while(t--)
{
  for(i=0;i<125;i++)
  {}
}
}

//串口初始化
void InitCom(void)
{
SCON = 0x50;//串口方式1，8位UART
TMOD = 0x20;//定时器T1，工作方式2，8位重载
PCON = 0x00;//波特率加倍
TH1 = 0xfd;
TL1 = 0xfd;
TR1 = 1;     //T1开始
ES = 1;
}

//发送一个ASCII
void SendASC(uchar ASC)
{
bit es;
es = ES;
ES = 0;
TI = 0;
SBUF = ASC;
while(!TI);
TI = 0;
ES = es;
}

//发送命令到Tc35i
void SendComTc35i(uchar *p,uchar Long)
{
while(Long--)
{
  SendASC(*p++);
}
}

//  通讯中断接收程序
void Rs232_Rxd(void) interrupt 4 using 1
{
if(RI==1)
{
  RI=0;
  RsBuf[FlagRs++]=SBUF;
  if(FlagRs>=sizeof(RsBuf))
  {
   FlagRs=0;
  }                 
}
}

//搜索Tc35i
/*void Search_Tc35i(void)
{
uchar *p;
while(1)
{
  ES = 1;
  p = strstr(RsBuf,Init_Tc35i);
  if(p != NULL) break;
}
}*/

//清缓冲区
void ClrRsBuf()
{
uchar len;
len = strlen(RsBuf);
while(len--)
{
  RsBuf[FlagRs++] = 0;
}
}

// 发送AT连机命令
void Send_AT(void)
{
uchar *p;
while(1)
{
     ClrRsBuf();
     SendComTc35i(AT_Tc35i,2);    //"AT"
     SendASC(0x0d);
                              
     ES=1;                        //等待应答"OK"
     Delay(1000);
  Delay(1000);
     p=strstr(RsBuf,AT_Code);
     if(p!=NULL) break;
}
}

//发送bps连机命令
/*void Send_BPS(void)
{
SendComTc35i(AT_Tc35i,3);    //"AT+"
SendComTc35i(Bps_Tc35,sizeof(Bps_Tc35)-1);//"IPR=19200"
SendASC(0x0d);
}*/




//发送短信息
void SendMsgStart(void)
{
uchar *p,i=250;
SendComTc35i(AT_Tc35i,3);    //"AT+"
SendComTc35i(Send_Tc35i,sizeof(Send_Tc35i)-1);//"AT+CMGS="
SendASC(0x22);
SendComTc35i(PhonNum,sizeof(PhonNum)-1);         
SendASC(0x22);                                //"AT+CMGS="PhonNum""
SendASC(0x0d);
ES=1;
while(i--)
{
    Delay(1500);        //Get">"
    p=strstr(RsBuf,SK);//">"
    if(p!=NULL)
    {
      ClrRsBuf();
      Delay(1000);    //Get">"
      break;
  }
}
}


void main(void)
{
while(1)
{
if(fa==0)
{EA = 1;
InitCom();
Delay(1000);
/*Search_Tc35i();
Delay(1000);*/
Send_AT();
Delay(1000);
//Send_BPS();
//ES=1;
//Delay(1000);
//ClrRsBuf();
SendComTc35i(AT_CSCA,19);
SendASC(0x0d);
ES=1;
Delay(1000);
ClrRsBuf();
SendComTc35i(AT_CMGF,9);
SendASC(0x0d);
ES=1;
Delay(1000);
ClrRsBuf();
SendMsgStart();
Delay(1000);
SendComTc35i(Test,sizeof(Test)-1);
SendASC(0x1a);
fa=1;}
}
}