/** Set the baud rate, where the baudrate is just the integer value
desired.
Returns non-zero on error.
**/
int
serial_set_baud (int fd, int baudrate)
{
struct termios tios;
#ifdef SUPPORT_HISPEED
struct serial_struct ser;
#endif
int baudratecode = serial_translate_baud (baudrate);
if (baudratecode > 0) {
// standard baud rate.
tcgetattr (fd, &tios);
cfsetispeed (&tios, baudratecode);
cfsetospeed (&tios, baudratecode);
tcflush (fd, TCIFLUSH);
tcsetattr (fd, TCSANOW, &tios);
#ifdef SUPPORT_HISPEED
ioctl (fd, TIOCGSERIAL, &ser);
ser.flags = (ser.flags&(~ASYNC_SPD_MASK));
ser.custom_divisor = 0;
ioctl (fd, TIOCSSERIAL, &ser);
#endif
}
else {
// non-standard baud rate.
#ifdef SUPPORT_HISPEED
// printf("Setting custom divisor\n");
if (tcgetattr (fd, &tios))
perror ("tcgetattr");
cfsetispeed (&tios, B38400);
cfsetospeed (&tios, B38400);
tcflush (fd, TCIFLUSH);
if (tcsetattr (fd, TCSANOW, &tios))
perror ("tcsetattr");
if (ioctl (fd, TIOCGSERIAL, &ser))
perror ("ioctl TIOCGSERIAL");
ser.flags = (ser.flags&(~ASYNC_SPD_MASK)) | ASYNC_SPD_CUST;
ser.custom_divisor = (ser.baud_base + baudrate/2)/baudrate;
ser.reserved_char[0] = 0; // what the hell does this do?
// printf("baud_base %i\ndivisor %i\n", ser.baud_base,ser.custom_divisor);
if (ioctl (fd, TIOCSSERIAL, &ser))
perror ("ioctl TIOCSSERIAL");
#endif
}
tcflush (fd, TCIFLUSH);
return 0;
}
/** Creates a basic fd, setting baud to 9600, raw data i/o (no flow
control, no fancy character handling. Configures it for blocking
reads.
Returns the fd, -1 on error
**/
int serial_open(const char *port, int baud, int blocking)
{
struct termios opts;
int flags = O_RDWR | O_NOCTTY;
if (!blocking)
flags |= O_NONBLOCK;
int fd=open(port, flags, 0);
if (fd==-1)
return -1;
if (tcgetattr(fd, &opts))
{
printf("*** %i\n",fd);
perror("tcgetattr");
return -1;
}
cfsetispeed(&opts, serial_translate_baud(9600));
cfsetospeed(&opts, serial_translate_baud(9600));
cfmakeraw(&opts);
// set one stop bit
opts.c_cflag &= ~CSTOPB;
if (tcsetattr(fd,TCSANOW,&opts)) {
perror("tcsetattr");
return -1;
}
tcflush(fd, TCIOFLUSH);
serial_set_baud(fd, baud);
return fd;
}
