如何在Linux上正确设置串口通信

但是,C方似乎存在问题.我一直在使用一些测试向量来测试FPGA是否正在输出正确的信息.我注意到了一些事情：

>设备有时无法正确打开
>终端属性有时无法检索或设置.
>读取有时是非阻塞的,并且不会检索正确的值.

下面是我如何设置终端和文件描述符选项.其中大部分来自这里：http://slackware.osuosl.org/slackware-3.3/docs/mini/Serial-Port-Programming

关于程序可能失败的任何建议或意见将非常有帮助.

#include <stdio.h>   // Standard input/output definitions
#include <string.h>  // String function definitions
#include <unistd.h>  // UNIX standard function definitions
#include <fcntl.h>   // File control definitions
#include <errno.h>   // Error number definitions
#include <termios.h> // POSIX terminal control definitions

int open_port(void){

    int fd;    // File descriptor for the port
    fd = open("/dev/ttyUSB0",O_RDWR | O_NOCTTY);

    if (fd == -1){
        fprintf(stderr,"open_port: Unable to open /dev/ttyUSB0 %sn",strerror(errno));
        exit(EXIT_FAILURE);
    }

    return (fd);
}

int main(void){

    int fd = 0;              // File descriptor
    struct termios options;  // Terminal options

    fd = open_port();    // Open tty device for RD and WR

    fcntl(fd,F_SETFL);            // Configure port reading
    tcgetattr(fd,&options);       // Get the current options for the port
    cfsetispeed(&options,B230400);    // Set the baud rates to 230400
    cfsetospeed(&options,B230400);

    options.c_cflag |= (CLOCAL | CREAD);    // Enable the receiver and set local mode
    options.c_cflag &= ~PARENB;             // No parity bit
    options.c_cflag &= ~CSTOPB;             // 1 stop bit
    options.c_cflag &= ~CSIZE;              // Mask data size
    options.c_cflag |=  CS8;                // Select 8 data bits
    options.c_cflag &= ~CRTSCTS;            // Disable hardware flow control  

    // Enable data to be processed as raw input
    options.c_lflag &= ~(ICANON | ECHO | ISIG);

    // Set the new attributes
    tcsetattr(fd,TCSANOW,&options);

    ////////////////////////////////////
    // Simple read and write code here//
    ////////////////////////////////////

    // Close file descriptor & exit
    close(fd)
    return EXIT_SUCCESS
}

UPDATE
我根据第一个答案修改了我的代码.这就是我现在拥有的：

#include <errno.h>      // Error number definitions
#include <stdint.h>     // C99 fixed data types
#include <stdio.h>      // Standard input/output definitions
#include <stdlib.h>     // C standard library
#include <string.h>     // String function definitions
#include <unistd.h>     // UNIX standard function definitions
#include <fcntl.h>      // File control definitions
#include <termios.h>    // POSIX terminal control definitions

// Open usb-serial port for reading & writing
int open_port(void){

    int fd;    // File descriptor for the port
    fd = open("/dev/ttyUSB0",strerror(errno));
        exit(EXIT_FAILURE);
    }

    return fd;
}

int main(void){

    int              fd = 0;     // File descriptor
    struct termios   options;    // Terminal options
    int              rc;         // Return value

    fd = open_port();            // Open tty device for RD and WR

    // Get the current options for the port
    if((rc = tcgetattr(fd,&options)) < 0){
        fprintf(stderr,"failed to get attr: %d,%sn",fd,strerror(errno));
        exit(EXIT_FAILURE);
    }

    // Set the baud rates to 230400
    cfsetispeed(&options,B230400);

    // Set the baud rates to 230400
    cfsetospeed(&options,B230400);

    cfmakeraw(&options);
    options.c_cflag |= (CLOCAL | CREAD);   // Enable the receiver and set local mode
    options.c_cflag &= ~CSTOPB;            // 1 stop bit
    options.c_cflag &= ~CRTSCTS;           // Disable hardware flow control
    options.c_cc[VMIN]  = 1;
    options.c_cc[VTIME] = 2;

    // Set the new attributes
    if((rc = tcsetattr(fd,"failed to set attr: %d,strerror(errno));
        exit(EXIT_FAILURE);
    }

    ////////////////////////////////
        // Simple Read/Write Code Here//
        ////////////////////////////////

    // Close file descriptor & exit
    close(fd);
    return EXIT_SUCCESS;
}

为了澄清,接收器和发送器使用8个数据位,1个停止位,没有奇偶校验位.