Linux下串口编程入门（二）

/**
*@brief 设置串口通信速率
*@param fd 类型 int 打开串口的文件句柄
*@param speed 类型 int 串口速度
*@return void
*/
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(fd1, TCSANOW, &Opt); 
 if (status != 0) { 
 perror("tcsetattr fd1"); 
 return; 
 } 
 tcflush(fd,TCIOFLUSH); 
 } 
 }
}

/**
*@brief 设置串口数据位，停止位和效验位
*@param fd 类型 int 打开的串口文件句柄
*@param databits 类型 int 数据位 取值 为 7 或者8
*@param stopbits 类型 int 停止位 取值为 1 或者2
*@param parity 类型 int 效验类型 取值为N,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) /*设置数据位数*/
 { 
 case 7: 
 options.c_cflag |= CS7; 
 break;
 case 8: 
 options.c_cflag |= CS8;
 break; 
 default: 
 fprintf(stderr,"Unsupported data sizen"); 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); /* 设置为奇效验*/ 
 options.c_iflag |= INPCK; /* Disnable parity checking */ 
 break; 
 case 'e': 
 case 'E': 
 options.c_cflag |= PARENB; /* Enable parity */ 
 options.c_cflag &= ~PARODD; /* 转换为偶效验*/ 
 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 parityn"); 
 return (FALSE); 
 } 
/* 设置停止位*/ 
switch (stopbits)
{ 
 case 1: 
 options.c_cflag &= ~CSTOPB; 
 break; 
 case 2: 
 options.c_cflag |= CSTOPB; 
 break;
 default: 
 fprintf(stderr,"Unsupported stop bitsn"); 
 return (FALSE); 
} 
/* Set input parity option */ 
if (parity != 'n') 
 options.c_iflag |= INPCK; 
tcflush(fd,TCIFLUSH);
options.c_cc[VTIME] = 150; /* 设置超时15 seconds*/ 
options.c_cc[VMIN] = 0; /* Update the options and do it NOW */
if (tcsetattr(fd,TCSANOW,&options) != 0) 
{ 
 perror("SetupSerial 3"); 
 return (FALSE); 
} 
return (TRUE); 
}

options.c_lflag &= ~(ICANON | ECHO | ECHOE | ISIG); /*Input*/
options.c_oflag &= ~OPOST; /*Output*/