receive.c

linux中串口通信程序。 有两个文件

#include     <stdio.h>      /*±ê׌ÊäÈëÊä³ö¶šÒå*/
#include     <stdlib.h>     /*±ê׌º¯Êý¿â¶šÒå*/
#include     <unistd.h>     /*Unix±ê׌º¯Êý¶šÒå*/
#include     <sys/types.h>  /**/
#include     <sys/stat.h>   /**/
#include     <fcntl.h>      /*ÎÄŒþ¿ØÖƶšÒå*/
#include     <termios.h>    /*PPSIXÖն˿ØÖƶšÒå*/
#include     <errno.h>      /*ŽíÎóºÅ¶šÒå*/

/***@brief  ÉèÖÃŽ®¿ÚÍšÐÅËÙÂÊ
*@param  fd     ÀàÐÍ int  Žò¿ªŽ®¿ÚµÄÎÄŒþŸä±ú
*@param  speed  ÀàÐÍ int  Ž®¿ÚËÙ¶È
*@return  void*/

#define TRUE 1
#define FALSE 0
#define MAX_MESSAGE 100
int speed_arr[] = { B38400, B19200, B9600, B4800, B2400, B1200, B300,
    B38400, B19200, B9600, B4800, B2400, B1200, B300,};
int name_arr[] = {38400,  19200,  9600,  4800,  2400,  1200,  300,
    38400,  19200,  9600, 4800, 2400, 1200,  300,};
void set_speed(int fd, int speed)
{
    int   i;
    int   status;
    struct termios   Opt;
    tcgetattr(fd, &Opt);
    for ( i= 0;  i < sizeof(speed_arr) / sizeof(int);  i++) {
        if (speed == name_arr[i]) {
            tcflush(fd, TCIOFLUSH);
            cfsetispeed(&Opt, speed_arr[i]);
            cfsetospeed(&Opt, speed_arr[i]);
            status = tcsetattr(fd, TCSANOW, &Opt);
            if (status != 0)
                perror("tcsetattr fd1");
            return;

        }
        tcflush(fd,TCIOFLUSH);
    }
}
/**
*@brief   ÉèÖÃŽ®¿ÚÊýŸÝλ£¬Í£Ö¹Î»ºÍЧÑéλ
*@param  fd     ÀàÐÍ  int  Žò¿ªµÄŽ®¿ÚÎÄŒþŸä±ú*
*@param  databits ÀàÐÍ  int ÊýŸÝλ   È¡Öµ Ϊ 7 »òÕß8*
*@param  stopbits ÀàÐÍ  int ֹͣλ   ȡֵΪ 1 »òÕß2*
*@param  parity  ÀàÐÍ  int  ЧÑéÀàÐÍ È¡ÖµÎªN,E,O,,S
*/
int set_Parity(int fd,int databits,int stopbits,int parity)
{
    struct termios options;
    if ( tcgetattr( fd,&options)  !=  0) {
        perror("SetupSerial 1");
        return(FALSE);
    }
    options.c_cflag &= ~CSIZE;
    switch (databits) { /*ÉèÖÃÊýŸÝλÊý*/
    case 7:
        options.c_cflag |= CS7;
        break;
    case 8:
        options.c_cflag |= CS8;
        break;
    default:
        fprintf(stderr,"Unsupported data size\n");
        return(FALSE);
    }
    switch (parity) {
    case 'n':
    case 'N':
        options.c_cflag &= ~PARENB;   /* Clear parity enable */
        options.c_iflag &= ~INPCK;     /* Enable parity checking */
        break;
    case 'o':
    case 'O':
        options.c_cflag |= (PARODD | PARENB);  /* ÉèÖÃΪÆæЧÑé*/ 
        options.c_iflag |= INPCK;             /* Disnable parity checking */
        break;
    case 'e':
    case 'E':
        options.c_cflag |= PARENB;     /* Enable parity */
        options.c_cflag &= ~PARODD;   /* ת»»ÎªÅŒÐ§Ñé*/  
        options.c_iflag |= INPCK;       /* Disnable parity checking */
        break;
    case 'S':
    case 's':  /*as no parity*/
        options.c_cflag &= ~PARENB;
        options.c_cflag &= ~CSTOPB;
        break;
    default:
        fprintf(stderr,"Unsupported parity\n");
        return(FALSE);
    }
    /* ÉèÖÃֹͣλ*/   
    switch (stopbits) {
    case 1:
        options.c_cflag &= ~CSTOPB;
        break;
    case 2:
        options.c_cflag |= CSTOPB;
        break;
    default:
        fprintf(stderr,"Unsupported stop bits\n");
        return(FALSE);
    }
    /* Set input parity option */
    if (parity != 'n')
        options.c_iflag |= INPCK;
    options.c_cc[VTIME] = 150; // 15 seconds
    options.c_cc[VMIN] = 0;

    tcflush(fd,TCIFLUSH); /* Update the options and do it NOW */
    if (tcsetattr(fd,TCSANOW,&options) != 0) {
        perror("SetupSerial 3");
        return(FALSE);
    }
    return(TRUE);
}
/**
*@breif Žò¿ªŽ®¿Ú
*/
int OpenDev(char *Dev)
{
    int fd = open( Dev, O_RDWR );         //| O_NOCTTY | O_NDELAY
    if (-1 == fd) { /*ÉèÖÃÊýŸÝλÊý*/
        perror("Can't Open Serial Port");
        return -1;
    } else
        return fd;

}

int SendData(int fd,char *str)
{
    //auto add the crlf
    char strbuf[1000];
    strcpy(strbuf, str);
    strcat(strbuf, "\r\n");
    write(fd, strbuf, strlen(strbuf));

    //printf("Send: <%s>\n", strbuf);
}

/**
*@breif 	main()
*/
int main(int argc, char **argv)
{
    int fd;
    int nread;
    char buff[512];
    char bufftemp[512];
    char *dev ="/dev/ttyS0";
    fd = OpenDev(dev);
    if (fd>0)
        set_speed(fd,9600);
    else {
        printf("Can't Open Serial Port!\n");
        exit(0);
    }

    if (set_Parity(fd,8,1,'N')== FALSE) {
        printf("Set Parity Error\n");
        exit(1);
    }
/*
    while (1) {
        int count =0;
        while (1) 
        {
            nread = 0;
            nread = read(fd,bufftemp,MAX_MESSAGE);
            memcpy(&buff[count],bufftemp,nread);
            count+=nread;
            if(count ==MAX_MESSAGE)
                break;
            else if(count>MAX_MESSAGE)
            {
                printf("strange! receive > send \n");
                break;
            }
        
        }
        //printf("\nLen %d\n",nread);
        buff[count]='\0';
        printf("\r\nRecv: <%s>\n",buff);
    }
*/
    while (1) 
    {
        memset(buff,0x0, MAX_MESSAGE);
        if((nread = read(fd,buff,MAX_MESSAGE))>0)
        {
           buff[nread]='\0';
            printf("\r\nRecv: <%s>\n",buff);
        }
    }
    close(fd);
    exit(0);
}