linux串口通信程序

/***************************** * 功能：设置串口函数 * 入口：（fd，波特率，数据位，奇偶校验，停止位） *****************************/ int set_opt(int fd,int nSpeed,int nBits,char nEvent,int nStop) { struct termios newtio,oldtio; /*保存测试现有串口参数设置，在这里如果串口号出错，会有相关的出错信息*/ if(tcgetattr(fd,&oldtio)!=0) { perror("SetupSerial 1"); return -1; } bzero(&newtio,sizeof(newtio)); /*步骤一：设置字符大小*/ newtio.c_cflag |= CLOCAL | CREAD; newtio.c_cflag &= ~CSIZE; /*设置停止位*/ switch(nBits) { case 7: newtio.c_cflag |= CS7; break; case 8: newtio.c_cflag |= CS8; break; } /*设置奇偶校验位*/ switch(nEvent) { case 'O': //奇数 newtio.c_cflag |= PARENB; newtio.c_cflag |= PARODD; newtio.c_iflag |= (INPCK | ISTRIP); break; case 'E': //偶数 newtio.c_iflag |= (INPCK | ISTRIP); newtio.c_cflag |= PARENB; newtio.c_cflag &= ~PARODD; break; case 'N': //无奇偶校验位 newtio.c_cflag &= ~PARENB; break; } /*设置波特率*/ switch (nSpeed) { case 2400: cfsetispeed(&newtio,B2400); cfsetospeed(&newtio,B2400); break; case 4800: cfsetispeed(&newtio,B4800); cfsetospeed(&newtio,B4800); break; case 9600: cfsetispeed(&newtio,B9600); cfsetospeed(&newtio,B9600); break; case 115200: cfsetispeed(&newtio,B115200); cfsetospeed(&newtio,B115200); break; case 460800: cfsetispeed(&newtio,B460800); cfsetospeed(&newtio,B460800); break; default : cfsetispeed(&newtio,B9600); cfsetospeed(&newtio,B9600); break; } /*设置停止位*/ if(nStop==1) { newtio.c_cflag &= ~CSTOPB; } else if (nStop==2) { newtio.c_cflag |= CSTOPB; } /*设置等待时间和最小接收字符*/ newtio.c_cc[VTIME]=0; newtio.c_cc[VMIN]=0; /*处理未接收字符*/ tcflush(fd,TCIFLUSH); /*激活新配置*/ if((tcsetattr(fd,TCSANOW,&newtio))!=0) { perror("COM set error/n"); return -1; } //printf("Set Done!/n"); return 0; } /***************************** * 功能：打开串口函数 *****************************/ int open_port(int fd,int comport) { char *dev[]={"/dev/ttyS0","/dev/ttyS1","/dev/ttyS2","/dev/ttyS3","/dev/ttyS4","/dev/ttyS5","/dev/ttyS6","/dev/ttyS7"}; long vdisable; fd=open(dev[comport-1],O_RDWR|O_NOCTTY|O_NDELAY); if(fd==-1) { perror("Can't Open Serial Port/n"); return -1; } /*恢复串口为阻塞状态*/ if(fcntl(fd,F_SETFL,0)<0) { printf("fcntl failed!/n"); } else printf("fcntl=%d/n",fcntl(fd,F_SETFL,0)); /*测试是否为终端设备*/ if(isatty(STDIN_FILENO)==0) { printf("standard input is not a terminal device/n"); } else printf("isatty success!/n"); printf("fd-open=%d/n",fd); return fd; } /***************************** * 功能：16进制ascii字符转数值 * [例]'A'转换后是0x0a *****************************/ char Hex2Char(char c) { if((c>='0')&&(c<='9')) return c-0x30; else if((c>='A')&&(c<='F')) return c-'A'+10; else if((c>='a')&&(c<='f')) return c-'a'+10; else return 0x10; }