#include <fcntl.h>
#include <pty.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>
#include <unistd.h>

void tty_raw(int fd)
{
	struct termios raw;

	if (tcgetattr(fd, &raw) == -1)
	{
		fprintf(stderr, "tcgetattr\r\n");
		exit(1);
	}
	raw.c_iflag &= ~(BRKINT | ICRNL | INPCK | ISTRIP | IXON);
	raw.c_oflag &= ~(OPOST);
	raw.c_cflag |= (CS8);
	raw.c_lflag &= ~(ECHO | ICANON | IEXTEN | ISIG);
	raw.c_cc[VMIN] = 0;
	raw.c_cc[VTIME] = 0; /* immediate - anything       */
	if (tcsetattr(fd, TCSAFLUSH, &raw) < 0)
	{
		fprintf(stderr, "can't set raw mode\r\n");
		exit(1);
	}
}

int main(int argc, char** argv)
{
	int fd = open("/dev/ttyUSB0", O_RDWR);

	struct termios tty;
	memset(&tty, 0, sizeof tty);
	tcgetattr(fd, &tty);
	cfsetospeed(&tty, B460800);
	cfsetispeed(&tty, B460800);

	tcsetattr(fd, TCSANOW, &tty);

	tty_raw(fd);

	int i = 0;
	for (;;)
	{
		char d[100];
		int len = sprintf(d, "data %d", i++);
		write(fd, d, len + 1);
		usleep(300000);
	}
}