LED-Cube/Cube Control/helper/unixSerial.c

/*
 * POSIX compatible serial port library
 * Uses 8 databits, no parity, 1 stop bit, no handshaking
 * By: Thomas Buck <taucher.bodensee@gmail.com>
 * Visit: www.xythobuz.org
 */

#include <stdio.h>
#include <unistd.h>
#include <fcntl.h>
#include <termios.h>

#define BAUD B19200

int fd = -1;

// Open the serial port
int serialOpen(char *port) {
	struct termios options;

	if (fd != -1) {
		close(fd);
	}
	fd = open(port, O_RDWR | O_NOCTTY | O_NDELAY);
	if (fd == -1) {
		return -1;
	}
	
	fcntl(fd, F_SETFL, FNDELAY); // read() isn't blocking'
	tcgetattr(fd, &options);
	cfsetispeed(&options, BAUD); // Set speed
	cfsetospeed(&options, BAUD);
	options.c_cflag |= (CLOCAL | CREAD);
	
	options.c_cflag &= ~PARENB; // 8N1
	options.c_cflag &= ~CSTOPB;
	options.c_cflag &= ~CSIZE;
	options.c_cflag |= CS8;
	
	options.c_lflag &= ~(ICANON | ECHO | ECHOE | ISIG); // Raw input
	options.c_oflag &= ~OPOST; // Raw output
	options.c_iflag &= ~(IXON | IXOFF | IXANY); // No flow control

	tcsetattr(fd, TCSANOW, &options);

	return 0;
}

// Write to port. Returns number of characters sent, -1 on error
ssize_t serialWrite(char *data, size_t length) {
	return write(fd, data, length);
}

// Read from port. Return number of characters read, 0 if none available, -1 on error
ssize_t serialRead(char *data, size_t length) {
	return read(fd, data, length);
}

// Close the serial Port
void serialClose(void) {
	close(fd);
}