linux+串口调试+源代码

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

int set_interface_attribs(int fd, int speed, int parity) {
    struct termios tty;
    memset(&tty, 0, sizeof(tty));
    if (tcgetattr(fd, &tty) != 0) {
        return -1;
    }

    cfsetospeed(&tty, speed);
    cfsetispeed(&tty, speed);

    tty.c_cflag = (tty.c_cflag & ~CSIZE) | CS8;     // 8-bit chars
    tty.c_iflag &= ~(IXON | IXOFF | IXANY);          // disable s/w flow ctrl
    tty.c_cflag = (tty.c_cflag & ~(PARENB | PARODD)) | parity; // set parity
    tty.c_cflag |= (CLOCAL | CREAD);                // ignore modem controls, enable reading
    tty.c_cflag &= ~(CSTOPB);                        // 1 stop bit
    tty.c_cc[VTIME] = 10;                            // 0.1 seconds timeout (deciseconds)
    tty.c_cc[VMIN] = 0;                              // no min chars to wait for

    if (tcsetattr(fd, TCSANOW, &tty) != 0) {
        return -1;
    }
    return 0;
}

void set_blocking(int fd, int should_block) {
    struct termios tty;
    memset(&tty, 0, sizeof(tty));
    if (tcgetattr(fd, &tty) != 0) {
        return;
    }

    tty.c_cc[VTIME] = should_block ? 10 : 0;
    tty.c_cc[VMIN] = should_block ? 1 : 0;

    if (tcsetattr(fd, TCSANOW, &tty) != 0) {
        return;
    }
}

int main() {
    char *portname = "/dev/ttyUSB0";
    int fd = open(portname, O_RDWR | O_NOCTTY | O_SYNC);
    if (fd < 0) {
        perror("error %d opening %s: %s", fd, portname, strerror(errno));
        return -1;
    }

    set_interface_attribs(fd, B9600, 0); // set speed to 9600 baud, 8N1 (no parity)
    set_blocking(fd, 0);                // set non-blocking

    char buf[100];
    memset(buf, '\0', sizeof(buf));
    read(fd, buf, sizeof(buf) - 1);     // read up to 100 characters if ready
    printf("Received: %s\n", buf);

    const char *msg = "Hello, Serial Port!";
    write(fd, msg, strlen(msg));        // send the message

    close(fd);
    return 0;
}