现在贴出来供大家参考。

#include

/************************************/
#include
#include
#include
#include
#include
#include
#include
#include
/***********************************/
#include
#include

int argc;
char **argv;
int fd,rc,ii,ret;
char rbuf[8];
char wbuf[8]="12345";

/****************/
int file,size,len;
int tmp_id=0;
int id_count=0;//已经收到的ID,计数
/****************/
char *dev ="/dev/ttyS1"; //串口号 /dev/ttyS1 对应于串口1

int openport(char *Dev)
{
int fd = open( Dev, O_RDWR|O_NOCTTY|O_NDELAY );
if (-1 == fd)
{
perror("Can''t Open Serial Port");
return -1;
}
else
return fd;
}

int setport(int fd, int baud,int databits,int stopbits,int parity)
{
int baudrate;
struct termios newtio;
switch(baud)
{
case 300:
baudrate=B300;
break;
case 600:
baudrate=B600;
break;
case 1200:
baudrate=B1200;
break;
case 2400:
baudrate=B2400;
break;
case 4800:
baudrate=B4800;
break;
case 9600:
baudrate=B9600;
break;
case 19200:
baudrate=B19200;
break;
case 38400:
baudrate=B38400;
break;
default :
baudrate=B9600;
break;
}
tcgetattr(fd,&newtio);
bzero(&newtio,sizeof(newtio));
//setting c_cflag
newtio.c_cflag &=~CSIZE;
switch (databits) /*设置数据位数*/
{
case 7:
newtio.c_cflag |= CS7; //7位数据位
break;
case 8:
newtio.c_cflag |= CS8; //8位数据位
break;
default:
newtio.c_cflag |= CS8;
break;
}
switch (parity) //设置校验
{
case 'n':
case 'N':
newtio.c_cflag &= ~PARENB; /* Clear parity enable */
newtio.c_iflag &= ~INPCK; /* Enable parity checking */
break;
case 'o':
case 'O':
newtio.c_cflag |= (PARODD | PARENB); /* 设置为奇效验*/
newtio.c_iflag |= INPCK; /* Disnable parity checking */
break;
case 'e':
case 'E':
newtio.c_cflag |= PARENB; /* Enable parity */
newtio.c_cflag &= ~PARODD; /* 转换为偶效验*/
newtio.c_iflag |= INPCK; /* Disnable parity checking */
break;
case 'S':
case 's': /*as no parity*/
newtio.c_cflag &= ~PARENB;
newtio.c_cflag &= ~CSTOPB;break;
default:
newtio.c_cflag &= ~PARENB; /* Clear parity enable */
newtio.c_iflag &= ~INPCK; /* Enable parity checking */
break;
}
switch (stopbits)//设置停止位
{
case 1:
newtio.c_cflag &= ~CSTOPB; //1
break;
case 2:
newtio.c_cflag |= CSTOPB; //2
break;
default:
newtio.c_cflag &= ~CSTOPB;
break;
}
newtio.c_cc[VTIME] = 0;
newtio.c_cc[VMIN] = 0;
newtio.c_cflag |= (CLOCAL|CREAD);
newtio.c_oflag|=OPOST;
newtio.c_iflag &=~(IXON|IXOFF|IXANY);
cfsetispeed(&newtio,baudrate);
cfsetospeed(&newtio,baudrate);
tcflush(fd, TCIFLUSH);
if (tcsetattr(fd,TCSANOW,&newtio) != 0)
{
perror("SetupSerial 3");
return -1;
}
return 0;
}

int readport(int fd,char *buf,int len,int maxwaittime)//读数据，参数为串口，BUF，长度，超时时间
{
int no=0;int rc;int rcnum=len;
struct timeva l tv;
fd_set readfd;
tv.tv_sec=maxwaittime/1000; //SECOND
tv.tv_usec=maxwaittime%1000*1000; //USECOND
FD_ZERO(&readfd);
FD_SET(fd,&readfd);
rc=select(fd+1,&readfd,NULL,NULL,&tv);
if(rc>0)
{
while(len)
{
rc=read(fd,&buf[no],1);
if(rc>0)
no=no+1;
len=len-1;
}
if(no!=rcnum)
return -1; //如果收到的长度与期望长度不一样，返回-1
return rcnum; //收到长度与期望长度一样，返回长度
}
else
{
return -1;
}
return -1;
}

void writeport(int fd,char *buf,int len) //发送数据
{
write(fd,buf,len);
}