Need help... sending sms through gsm900 with PIC18F4550

[Veeramani.T]

dear friends,
i used pic18f4550 for sending sms through gsm900.
i got the at commands correctly in hyper terminal.
the problem is ......
manually i send the AT commands from hyperterminal to gsm900, the module is sending the sms to my mobile.
but, gsm module is connected to PIC MC , i could not get the sms.
and my hardware connections are correct ( checked it)
i dont know what is happening?

my code is ...

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#include<xc.h>
#include<usart.h>
 
#pragma config PLLDIV = 4, CPUDIV = OSC1_PLL2, FOSC = HS, FCMEN = OFF, IESO = OFF, PWRT = OFF, BOR = ON, BORV = 3, WDT = OFF, WDTPS = 32768
#pragma config MCLRE = ON, LPT1OSC = OFF, PBADEN = ON, CCP2MX = ON, STVREN = ON, LVP = OFF, XINST = OFF, VREGEN = OFF, ICPRT = OFF, DEBUG = ON
#pragma config CP0 = OFF, CP1 = OFF, CP2 = OFF, CP3 = OFF, CPB = OFF, CPD = OFF, WRT0 = OFF, WRT1 = OFF, WRT2 = OFF, WRT3 = OFF
#pragma config WRTB = OFF, WRTC = OFF, WRTD = OFF, EBTR0 = OFF, EBTR1 = OFF, EBTR2 = OFF, EBTR3 = OFF, EBTRB = OFF
 
void string(unsigned char *s);
unsigned int i=0,j;
unsigned char serial_data;
 
#define FREQ 20000000 // Frequency = 20MHz
#define baud 9600
#define spbrg_value (((FREQ/64)/baud)-1) 
 
 
void string(unsigned char *s)
{
while(*s!=0x0)
{
TXREG=*s;
for (j=0;j<100;j++);
while(PIR1bits.TXIF==0)
{
}
PIR1bits.TXIF==0;
s++;
}
}
 
void tx_data(unsigned char data1)
{
TXREG=data1; 
while(PIR1bits.TXIF==0); 
PIR1bits.TXIF=0;
}
 
void d1(void)
{
for (j=0;j<60000;j++);
for (j=0;j<60000;j++);
for (j=0;j<60000;j++);
for (j=0;j<60000;j++);
for (j=0;j<60000;j++);
for (j=0;j<60000;j++);
for (j=0;j<60000;j++);
for (j=0;j<60000;j++);
for (j=0;j<60000;j++);
for (j=0;j<60000;j++);
for (j=0;j<60000;j++);
for (j=0;j<60000;j++);
for (j=0;j<60000;j++);
for (j=0;j<60000;j++);
}
 
void main(void)
{
TXSTAbits.SYNC=0;
BAUDCONbits.BRG16=0;
TXSTAbits.BRGH=0;
 
SPBRG=spbrg_value; 
RCSTAbits.SPEN=1; 
TXSTAbits.TXEN=1; 
RCSTAbits.CREN=1; 
while(1)
{
string("AT\r\n");
d1(); d1(); d1(); d1(); 
 
string("AT+CMGF=1\r\n");
d1(); d1(); d1(); d1();
 
string("AT+CMGS=\"+91xxxxxxxxxx\"\r\n");
d1(); d1(); d1(); d1();
 
string("This is my test msg");
d1(); d1(); d1(); d1();
 
tx_data(0x1A);
d1(); d1(); d1(); d1();
 
}
}

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