``c，#include，#include，#include，#include，，int main() {， int serial_port = open("/dev/ttyS0", O_RDWR);， if (serial_port< 0) {， perror("Failed to open the serial port");， return 1;， }，， struct termios tty;， if (tcgetattr(serial_port, &tty) != 0) {， perror("Failed to get attributes of the serial port");， close(serial_port);， return 1;， }，， cfsetospeed(&tty, B9600);， cfsetispeed(&tty, B9600);，， tty.c_cflag &= ~PARENB; // No parity bit， tty.c_cflag &= ~CSTOPB; // 1 stop bit， tty.c_cflag &= ~CSIZE;， tty.c_cflag |= CS8; // 8 bits per byte， tty.c_cflag &= ~CRTSCTS;// No hardware flow control， tty.c_cflag |= CREAD | CLOCAL; // Turn on READ & ignore ctrl lines，， tty.c_lflag &= ~ICANON;， tty.c_lflag &= ~ECHO; // Disable echo， tty.c_lflag &= ~ECHOE; // Disable erasure， tty.c_lflag &= ~ECHONL; // Disable new-line echo， tty.c_lflag &= ~ISIG; // Disable interpretation of INTR, QUIT and SUSP，， tty.c_iflag &= ~(IXON | IXOFF | IXANY); // Turn off s/w flow ctrl， tty.c_iflag &= ~(IGNBRK|BRKINT|PARMRK|ISTRIP|INLCR|IGNCR|ICRNL); // Disable special handling of received bytes，， tty.c_oflag &= ~OPOST; // Prevent special interpretation of output bytes (e.g. newline chars)， tty.c_oflag &= ~ONLCR; // Prevent conversion of newline to carriage return/line feed，， tty.c_cc[VTIME] = 10; // Wait for up to 1s (10 deciseconds), returning as soon as any data is received.， tty.c_cc[VMIN] = 0;，， if (tcsetattr(serial_port, TCSANOW, &tty) != 0) {， perror("Failed to set attributes of the serial port");， close(serial_port);， return 1;， }，， char msg[] = "Hello, serial port!";， write(serial_port, msg, sizeof(msg));，， close(serial_port);， return 0;，}，``