UART looping Back

Hello,
I am using rockpi s and trying to access UART1.
Able to send data properly but while receiving, data is getting looped back.
Not able to receive data.

struct termios ti;
int main()
{

int fd;
fd = open("/dev/ttyS1", O_RDWR | O_NOCTTY | O_SYNC);
    if (fd < 0) {
        perror("Can't open serial port");
        return -1;
    }
tcflush(fd, -TCIOFLUSH);

if (tcgetattr(fd, &ti) < 0) {
    perror("Can't get port settings");
    return -1;
}
// cfmakeraw(ti);
int flags = fcntl(fd, F_GETFL, 0);
    fcntl(fd, F_SETFL, flags | O_NONBLOCK);
    cfsetospeed(&ti,B9600 );
    cfsetispeed(&ti, B9600);
if (tcsetattr(fd, TCSANOW,&ti) < 0) {
    printf("Can't set speed\n");
    return -1;
}
ti.c_cflag |= PARENB;

ti.c_cflag &=~ CSTOPB;

char arr[]="abcdefg";
char readbuf[100];
memset(readbuf,0,10);

int count=write(fd, arr, sizeof(arr));

printf("Bytes transfered=%d\n",count);
while(1){
    int read_bytes=read(fd,readbuf,100);

    if (read_bytes>0)
    printf("%s",readbuf);
}

}
This is how i am trying to use UART.