CCS/TM4C1294NCPDT: Receiving GPS data in PC serial port and ARDUINO UART Port also, but not receiving the GPS Data in TM4C1294NCPDT UART PORT

#include <stdio.h>
#include <string.h>
#include <stdbool.h>
#include <stdint.h>
#include "driverlib/sysctl.h"
#include "driverlib/gpio.h"
#include "driverlib/pin_map.h"
#include "inc/hw_gpio.h"
#include "inc/hw_memmap.h"
#include "inc/hw_types.h"
#include "utils/uartstdio.h"
#include "utils/uartstdio.c"
#include "driverlib/uart.h"
#include "inc/hw_uart.h"

/**
 * main.c
 */

uint8_t gps_data[1000],ch1[80],gps_data1[100],ch;
uint32_t ui32SysClkFreq,i=0;
void ON_OFF(void)                                                   // ON_OFF Pulse Generate
{

    SysCtlDelay(20000000);        
    GPIOPinWrite(GPIO_PORTP_BASE , GPIO_PIN_2 , GPIO_PIN_2);
    SysCtlDelay(20000000);        
    GPIOPinWrite(GPIO_PORTP_BASE , GPIO_PIN_2 , 0);
    SysCtlDelay(4000000);        
}
void GPS_Init(void)
{
	SysCtlPeripheralEnable(SYSCTL_PERIPH_UART2);
	SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOA);
	GPIOPinConfigure(GPIO_PA6_U2RX);
	GPIOPinConfigure(GPIO_PA7_U2TX);
	GPIOPinTypeUART(GPIO_PORTA_BASE, GPIO_PIN_6 | GPIO_PIN_7);
	UARTConfigSetExpClk(UART2_BASE, ui32SysClkFreq ,4800,(UART_CONFIG_WLEN_8 | UART_CONFIG_STOP_ONE | UART_CONFIG_PAR_NONE));
}

int main(void)
{
	ui32SysClkFreq = SysCtlClockFreqSet((SYSCTL_XTAL_25MHZ | SYSCTL_OSC_MAIN | SYSCTL_USE_PLL | SYSCTL_CFG_VCO_480), 120000000);
	GPS_Init();
	ON_OFF();
	while(1)
	{
    		 if(UARTCharsAvail(UART2_BASE))
    		    	gps_data[i++]  = UARTCharGet(UART2_BASE);
	
		if(i==1000)
			i = 0;

	}
}