linux c 串口收发数据

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <fcntl.h>
#include <errno.h>
#include <termios.h>

int open_serial_port(const char *port) {
    int fd = open(port, O_RDWR | O_NOCTTY | O_NDELAY);
    if (fd == -1) {
        perror("open_serial_port: Unable to open port");
        return -1;
    }

    struct termios options;
    tcgetattr(fd, &options);
    cfsetispeed(&options, B9600); // 设置波特率
    cfsetospeed(&options, B9600);
    options.c_cflag |= (CLOCAL | CREAD); // 启用接收器并忽略本地回环
    options.c_cflag &= ~PARENB; // 无校验
    options.c_cflag &= ~CSTOPB; // 1个停止位
    options.c_cflag &= ~CSIZE;
    options.c_cflag |= CS8; // 8位数据位
    tcsetattr(fd, TCSANOW, &options);

    return fd;
}

void close_serial_port(int fd) {
    close(fd);
}

int read_serial_port(int fd, char *buffer, int length) {
    int n = read(fd, buffer, length);
    if (n < 0) {
        perror("read_serial_port: Unable to read from port");
        return -1;
    }
    return n;
}

int write_serial_port(int fd, const char *buffer, int length) {
    int n = write(fd, buffer, length);
    if (n < 0) {
        perror("write_serial_port: Unable to write to port");
        return -1;
    }
    return n;
}

int main() {
    int fd = open_serial_port("/dev/ttyS0"); // 打开串口设备
    if (fd == -1) {
        return 1;
    }

    char write_buffer[] = "Hello, Serial!";
    write_serial_port(fd, write_buffer, strlen(write_buffer));

    char read_buffer[256];
    int n = read_serial_port(fd, read_buffer, sizeof(read_buffer));
    if (n > 0) {
        read_buffer[n] = '\0';
        printf("Received: %s
", read_buffer);
    }

    close_serial_port(fd);
    return 0;
}