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我无法通过串口读取字节 0x11 和 0x13。资源：

    int fd; /* File descriptor for the port */
    fd = open(PORT_PATH, O_RDWR | O_NOCTTY);// ); | O_NDELAY
    if (fd == -1){//Could not open the port.
        fprintf(stderr, "open_port: Unable to open %s - %s\n", PORT_PATH, strerror(errno));
        return fd;
    }

    struct termios settings;
    tcgetattr(fd, &settings);
    cfsetispeed(&settings, B38400); // baud rate
    cfsetospeed(&settings, B38400); // baud rate
    settings.c_cflag &= ~PARENB; // no parity
    settings.c_cflag &= ~CSTOPB; // 1 stop bit
    settings.c_cflag &= ~CSIZE;
    settings.c_cflag &= ~CRTSCTS;
    settings.c_cflag |= (CS8 | CLOCAL | CREAD);
    settings.c_cc[VMIN] = 1;
    settings.c_cc[VTIME] = 0;
    tcflush(fd, TCIOFLUSH);
    tcsetattr(fd, TCSANOW, &settings);// apply the settings

    char data, rcv;
    data = 0x10;
    write(fd, &data, 1);
    read(fd, &rcv, 1);
    printf("rcv_data = 0x%02X\n", rcv);

    data = 0x12;
    write(fd, &data, 1);
    read(fd, &rcv, 1);
    printf("rcv_data = 0x%02X\n", rcv);

    data = 0x88;
    write(fd, &data, 1);
    read(fd, &rcv, 1);
    printf("rcv_data = 0x%02X\n", rcv);

    data = 0x13;
    write(fd, &data, 1);
    read(fd, &rcv, 1);
    printf("rcv_data = 0x%02X\n", rcv);

    data = 0x11;
    write(fd, &data, 1);
    read(fd, &rcv, 1);
    printf("rcv_data = 0x%02X\n", rcv);

    close(fd);

Tx 和 Rx 已连接。在控制台输出中：

rcv_data = 0x10
rcv_data = 0x12
rcv_data = 0x88

没有更多了。无法接收传输的字节 0x13。在示波器上我看到传输的 0x13，但我不明白为什么这个字节没有接收到。与 0x11 字节相同。其他字节没问题。

4

1 回答 1

2

0x11和0x13是XON/XOFF 流控制字符（Control-Q和Control-S）。如果您希望能够发送和接收这些字符，您将需要禁用 XON/XOFF 流控制，例如

setting.c_iflag &= ~(IXOFF | IXON);
于 2014-06-09T10:05:12.257 回答