linux 串口编程

串口的头文件：

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <termios.h>
#include <errno.h>
#include <string.h>

串口的参数设置：

/* set the terminal parameter */
void m_setparms(int fd)
{
    struct termios tty;
    int spd = B115200;

    tcgetattr(fd, &tty);

    cfsetospeed(&tty, spd); //set the speed to 115200
    cfsetispeed(&tty, spd);

    tty.c_cflag = (tty.c_cflag & ~CSIZE) | CS8; // 8 bits data

    /* Set into raw, no echo mode */
    tty.c_iflag =  IGNBRK;
    tty.c_lflag = 0;
    tty.c_oflag = 0;
    tty.c_cflag |= CLOCAL | CREAD;

#ifdef _DCDFLOW
    tty.c_cflag &= ~CRTSCTS;
#endif

    tty.c_cc[VMIN] = 1;
    tty.c_cc[VTIME] = 5;

    tty.c_iflag &= ~(IXON|IXOFF|IXANY);

    tty.c_cflag &= ~(PARENB | PARODD);  // no parity
    tty.c_cflag &= ~CSTOPB;

    tcsetattr(fd, TCSANOW, &tty);
}

主函数打开串口：

int main(int argc, char **argv)
{
    int fd, i, len;
    struct timeval tv;
    char buf[1024];
    char *p;

    if (argc != 2) {
        printf("Usage: dcm board_type\n");
        exit(0);
    }
    for (i=0; i<2; i++) {
        //if (strcmp(
    }

    fd = open(DEV, O_RDWR | O_NDELAY | O_NOCTTY);
    if (fd < 0)
    {
        perror("Can't Open Serial Port");
        return -1;
    } else {
        i = fcntl(fd, F_GETFL, 0);
        fcntl(fd, F_SETFL, i & ~O_NDELAY);
        m_setparms(fd);
    }

    printf("Serial Port configure complete \n");
｝

串口的读写函数为：read/write