stty -F /dev/ttyO0 speed 115200
stty -F /dev/ttyO0 raw
stty -F /dev/ttyO0 speed 115200
stty -F /dev/ttyO0 -echo

#define TIOCGRS485      0x542e
#define TIOCSRS485      0x542f

struct serial_rs485 rs485conf;
if ((ttydev = open( argv[i + 1], O_RDWR | O_NOCTTY | O_NONBLOCK)) < 0)
    errOut( "\nERROR parsevil: TTY device could not be opened: %s\n\n", argv[i + 1]);

rs485conf.flags |= SER_RS485_ENABLED;
rs485conf.flags |= SER_RS485_RTS_ON_SEND;
if (ioctl (ttydev, TIOCSRS485, &rs485conf) < 0)
{
	printf("ioctrl Error handling. See errno. \n");
}else
{
	printf("set rs485 ok\n");
}