Setting non-standard baud rate to Serial Port

Using stty, we can only set standard baud rates such as 9600, 19200, 38400, 57600 and so on using the following command:

stty -F /dev/ttyUSB0 115200

stty does not allow us to set non-standard baud rate , for example 7667.

stty -F /dev/ttyUSB0 7667

We will get the following error: "stty: invalid argument '7667'

We can set a custom baud rate using new style termios2 struct with setting BOTHER flag in c_flag member of termios2 struct.

Sample Code for setting custom baud rate

#include <stdio.h>

#include <fcntl.h>

#include <errno.h>

#include <asm/termios.h>

int main()

{

    int fd, ret;

    struct termios2 config;

    fd = open("/dev/ttyUSB0", O_RDWR);

    if (fd < 0)

        printf("Failed to open /dev/ttyUSB0 - fd = %d\n", fd);

    // Set custom buad rate

    ret = ioctl(fd, TCGETS2, &config);

     if (!ret) {

        config.c_cflag &= ~CBAUD;

        config.c_cflag |= BOTHER;

        config.c_ispeed = 7667;

        config.c_ospeed = 7667;

        ret = ioctl(fd, TCSETS2, &config);

}

    close(fd);

    return ret;

}