SIM808 (ATE0) echo problem

#include "p18f4580.h"
#include "xc.h"
#include "htc.h"
#include "stdio.h"
#include "string.h"
#include "stdlib.h"
// #include <delays.h>

#define FREQ 12000000
#define baud 9600
#define spbrg_value (((FREQ/64)/baud)-1)
#define rs LATAbits.LATA0
#define rw LATAbits.LATA1
#define en LATAbits.LATA2
#define lcdport LATD
#define _XTAL_FREQ 20000000

void tx_data(unsigned char);
unsigned char rx_data();
void lcd_ini();
void lcdcmd(unsigned char);
void lcddata(unsigned char);
void gsm_cmd(unsigned char *);
void led_blink(char * ,char *,char *);
void output(void);
 
 
 
int i=0,j=0,k,temp,flag,choice,id;
unsigned char *starting_text = "Welcome";
unsigned char *at_cmd = "AT";
unsigned char *echo_off = "ATE0&W";
unsigned char *imei_cmd = "AT+GSN";
unsigned char *sms_format = "AT+CMGF=1";
unsigned char *sms_inc = "AT+CNMI=\"1,1,0,0,0\""; // checks if message is received
unsigned char *sms_send = "AT+CMGS=\"xxxxxxxxxx\""; // 10-Digit Mobile Number
unsigned char *sms = "Hello  0x1A";
unsigned char *gps_on = "AT+CGPSPWR=1";
unsigned char *gps_rst = "AT+CGPSRST=2";
unsigned char *gps_sts ="AT+CGPSSTATUS?";
unsigned char *gps_inf = "AT+CGPSINF=0"; // to send command GPS info from pic to gsm
unsigned char *store_loc = "AT+CPMS=\"<SM,SM>\""; //Received msg location
unsigned char enter=0x0D; // carriage return
unsigned char l_feed=0x0A; // line feed
volatile unsigned char *data;
void main()
{
TRISA = 0;
LATA = 0;
TRISD = 0; //Set port D for LCD interface
LATD = 0;
TRISB = 0;// Set port B for LED interface/CAN interface(RB2 & RB3)
LATB = 0;
TRISCbits.TRISC6 = 0;
TRISCbits.TRISC7 = 1;
TXSTAbits.SYNC = 0; // Enable UART comm
SPBRG= spbrg_value; // Fill SPBRG register to set the baud rate
RCSTAbits.SPEN = 1; // To activate serial port (Tx and Rx pins)
TXSTAbits.TXEN = 1; // Activate Transmissiom
TXSTAbits.BRGH = 1; // high baud rate mode
RCSTAbits.CREN=1; // Activate Reception
PIE1bits.RCIE=1; // Enable Reception interrupt
INTCONbits.GIE=1; // Enable Global interrupt
INTCONbits.PEIE=1; // Enable Peripheral interrupt
char adr[30];
char strtype[10];
char stoloc[10];
char adr[30];
char strtype[10];
char stoloc[10];

lcd_ini();
k=0;
lcdcmd(0x80);
while(starting_text[k]!='\0')
{
    lcddata(starting_text[k]);
    k++;
}

    gsm_cmd(at_cmd);
    __delay_ms(1000);
    output();
    __delay_ms(1000);

    gsm_cmd(echo_off);
    __delay_ms(1000);
    output();
    __delay_ms(1000);


    gsm_cmd(imei_cmd);
    __delay_ms(1000);
    output();
    __delay_ms(1000);

    gsm_cmd(gps_on);
    __delay_ms(1000);
    output();
    __delay_ms(1000);

    gsm_cmd(gps_rst);
    __delay_ms(1000);
    output();

    check: gsm_cmd(gps_sts);
    if(strcmp(data,"+CGPSSTATUS:Location 2D Fix ")==0)
    {
        output();
        __delay_ms(1000);
    }
    else if(strcmp(data,"+CGPSSTATUS:Location 3D Fix")==0)
    {
        output();
        __delay_ms(1000);
    }
    else
    {
        goto check;
    }

    gsm_cmd(store_loc);
    output();
    __delay_ms(1000);

    gsm_cmd(sms_format);
    output();
    __delay_ms(1000);

    gsm_cmd(sms_send);
    output();
    __delay_ms(1000);

    if(RCREG=">")
    {
        gsm_cmd(sms);
        output();
        __delay_ms(1000);
    }

    gsm_cmd(sms_inc);
    output();
    __delay_ms(1000);

int k;
for(k=0;k<=300000;k++)
{
    if(strncmp(data,"+CMTI: \"SM\",",12)==0)
         break;
}
 strcpy(adr,data);
 strtok(adr, ",");
 strcpy(strtype, strtok(NULL, ","));
 strcpy(stoloc, strtok(NULL, ","));
 id= atoi(stoloc);

}
void gsm_cmd(unsigned char *string)
{
    i=0;j=0;
    while(string[i]!='\0')
    {
        if(string[i]==0x5C) // Not to send '\' character
            i++;
        tx_data(string[i]); // Send by serial communication
        i++;
    }
    tx_data(enter); // Send ASCII code for 'Enter' key
    tx_data(l_feed);
}

void output(void) // To print data on LCD
{
    lcdcmd(0x01);
    i=0;flag=0;
    while(i<j)
    {
        if(flag>1)
        {
            flag=0;
            __delay_ms(500);
            lcdcmd(0x01);
            lcdcmd(0x80);
        }
        if(data[i]==0x0A) // This condition is to avoid double Enter
                          // during execution of a command
        {
            flag++;
            lcdcmd(0xc0);
        }
        if(data[i]=='>'||data[i]=='"') // Not to print this character
        {
            i++;
            lcdcmd(0xc0);
        }
        if(data[i]!=0x0D&&data[i]!=0x0A&&data[i]!=0x1A) // Condition to print the data
                                                        // except 'Enter','New line' and 'Submit'
        {
            lcddata(data[i]);
            i++;
        }
        else
            i++;
            __delay_ms(300);
    }
 
j=0; // after reading set j=0
    lcdcmd(0x01);
}

void tx_data(unsigned char serial_data) // Transmit data function
{
    while(PIR1bits.TXIF==0);
    TXREG=serial_data;
}

void interrupt SerialRxPinInterrupt()
{
    while(!PIR1bits.RCIF);
    data[j]= RCREG;  // Store the data into array when Reception interrupt occurs
        j++;
}

void lcd_ini()
{
    lcdcmd(0x38); // Configure the LCD in 8-bit mode, 2 line and 5x7 font
    lcdcmd(0x0C); // Display On and Cursor Off
    lcdcmd(0x01); // Clear display screen
    lcdcmd(0x06); // Increment cursor
    lcdcmd(0x80); // Set cursor position to 1st line, 1st column
}

void lcdcmd(unsigned char cmdout)
{
    lcdport = cmdout; //Send command to lcdport=PORTB
    rs = 0;
    rw = 0;
    en = 1;
    __delay_ms(10);
    en =0;
}

void lcddata(unsigned char dataout)
{
    lcdport=dataout; //Send data to lcdport=PORTB
    rs = 1;
    rw = 0;
    en = 1;
    __delay_ms(10);
    en = 0;
}