int sendTo(char *portName, const unsigned char *message, size_t len) {
	struct termios tio;
	int tty_fd;
	fd_set rdset;

	memset(&tio,0,sizeof(tio));
	tio.c_iflag=0;
	tio.c_oflag=0;
	tio.c_cflag=CS8|CREAD|CLOCAL;           
	tio.c_lflag=0;
	tio.c_cc[VMIN]=1;
	tio.c_cc[VTIME]=5;
	printf("Open %s\n", portName);
	tty_fd=open(portName, O_RDWR | O_NOCTTY | O_NONBLOCK);
	if(tty_fd == -1) {
		perror("Port not open");
		return -1;
	}
	cfsetospeed(&tio,B38400);
	cfsetispeed(&tio,B38400);

	tcsetattr(tty_fd,TCSANOW,&tio);

	int result;
	do {
		result = write(tty_fd, message,len);
		if(result == -1) {
			perror("Error");
			close(tty_fd);
			return -1;
		}		
		message += result;
		len -= result;
	} while(len > 0);

	close(tty_fd);
	return 0;
}

#include <stdlib.h>
#include <stdio.h>

#include <unistd.h>
#include "rs232.h"

void printBytes(const unsigned char *ptStr, size_t len) {
	while(len--)
		printf("%0.2x ", *ptStr++);
	printf("\n");
}

int main(int argc, char *argv[]) {

	int bdrate=38400;
	int serialNum = 3;
	int serialAlt = 1;

	if(argc < 2) return -1;

	char buffer[256];

	//CMD Clear 		0x0f 0x01
	//CMD Set Cursor 	0x0f 0x80

	sprintf(buffer, "\x0f\x01\x0f\x80%s", argv[1]);

	OpenComport(serialNum, bdrate);

	printf("Send: ");
	printBytes(buffer, strlen(buffer));

	SendBuf(serialNum, buffer, strlen(buffer));
	//
	OpenComport(serialAlt, bdrate);
	SendBuf(serialAlt, "\x0", 1);
	CloseComport(serialAlt);
	//
	CloseComport(serialNum);

   printf("END\n");
   return 0;
}