LINUX环境,串口通讯案例源代码参考.doc

LINUX环境，串口通讯案例源代码参考 #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 #include sys/time.h #include mysql/mysql.h #include math.h #include sys/io.h #define FALSE -1 #define TRUE 1 int my_write(int fd,void *buffer,int length) { int bytes_left; int written_bytes; char *ptr; ptr=buffer; bytes_left=length; while(bytes_left0) { written_bytes=write(fd,ptr,bytes_left); if(written_bytes0) { if(errno==EINTR) written_bytes=0; else return(-1); } bytes_left-=written_bytes; ptr+=written_bytes; } return(0); } // 16位crc校验 void checksum(unsigned char *data,unsigned char *check,int n){ long temp=0; int i; for(i=0;in;i++){ temp=temp+data[i]; } temp=(~temp)+0x01; check[0]=((temp8)0xff); check[1]=(temp0xff); } void lchecksum(unsigned char lenid,char *lenth){ // 16位crc校验 *(lenth+3)=lenid0x0f; *(lenth+2)=(lenid4)0x0f; *(lenth+1)=(lenid8)0x0f; *lenth=(~(((*(lenth+3))+(*(lenth+2))+(*(lenth+1)))%16)+1)0x0f; } //定义内核bott常量对照表 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, }; //定义bott率 void set_speed(int fd, int speed) { int i,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); } } //定义其他串口参数 in