comconfig.c

嵌入式 linux 扩展串口 驱动 测试程序

#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>

#define UART_RS485_CONFIG 0x5AA1

typedef unsigned char U8;
typedef unsigned short U16;
typedef unsigned long U32;

#define  CMSPAR 010000000000
void setTermios(struct termios * pNewtio, U16 uBaudRate)
{
        bzero(pNewtio, sizeof(struct termios)); /* clear struct for new port settings */

        //8N1
        //pNewtio->c_cflag = uBaudRate | CS8 |  CREAD | CLOCAL;
        //pNewtio->c_iflag = IGNPAR;

        //8E1
        //pNewtio->c_cflag = uBaudRate | CS8 |  CREAD | CLOCAL |PARENB;
        //pNewtio->c_iflag = 0;

        //8O1
        //pNewtio->c_cflag = uBaudRate | CS8 |  CREAD | CLOCAL |PARENB | PARODD;
        //pNewtio->c_iflag = 0;

        //8S1
        //pNewtio->c_cflag = uBaudRate | CS8 |  CREAD | CLOCAL |PARENB | CMSPAR;
        //pNewtio->c_iflag = 0;

        //8M1
        pNewtio->c_cflag = uBaudRate | CS8 |  CREAD | CLOCAL |PARENB | PARODD | CMSPAR;
        pNewtio->c_iflag = 0;

        pNewtio->c_oflag = 0;
        pNewtio->c_lflag = 0; //non ICANON
        /*
        initialize all control characters
        default values can be found in /usr/include/termios.h, and
        are given in the comments, but we don't need them here
        */
        pNewtio->c_cc[VINTR]    = 0;     /* Ctrl-c */
        pNewtio->c_cc[VQUIT]    = 0;     /* Ctrl-\ */
        pNewtio->c_cc[VERASE]   = 0;     /* del */
        pNewtio->c_cc[VKILL]    = 0;     /* @ */
        pNewtio->c_cc[VEOF]     = 4;     /* Ctrl-d */
        pNewtio->c_cc[VTIME]    = 5;     /* inter-character timer, timeout VTIME*0.1 */
        pNewtio->c_cc[VMIN]     = 0;     /* blocking read until VMIN character arrives */
        pNewtio->c_cc[VSWTC]    = 0;     /* '\0' */
        pNewtio->c_cc[VSTART]   = 0;     /* Ctrl-q */
        pNewtio->c_cc[VSTOP]    = 0;     /* Ctrl-s */
        pNewtio->c_cc[VSUSP]    = 0;     /* Ctrl-z */
        pNewtio->c_cc[VEOL]     = 0;     /* '\0' */
        pNewtio->c_cc[VREPRINT] = 0;     /* Ctrl-r */
        pNewtio->c_cc[VDISCARD] = 0;     /* Ctrl-u */
        pNewtio->c_cc[VWERASE]  = 0;     /* Ctrl-w */
        pNewtio->c_cc[VLNEXT]   = 0;     /* Ctrl-v */
        pNewtio->c_cc[VEOL2]    = 0;     /* '\0' */
}


int main(int argc, char **argv)
{
        int fd;
        int nCount,nTotal,i;
        struct termios oldtio,newtio;
        char *dev ="/dev/ttyS2";

        if ( (fd = open(dev,O_RDWR | O_NOCTTY ))<0)
        {
                printf("Can't Open Serial Port!\n");
                return -1;
        }

        tcgetattr(fd,&oldtio); /* save current serial port settings */
        setTermios(&newtio,B115200);

        tcflush(fd, TCIFLUSH);
        tcsetattr(fd,TCSANOW,&newtio);

        ioctl(fd,UART_RS485_CONFIG,0);

        tcsetattr(fd,TCSANOW,&oldtio);
    
        close(fd);
        return 0;
}