十六进制串口发送

字符串转化为十六进制，让串口发送数据：

int hexdata, lowhexdata;unsigned short int hexdatalen = 0;unsigned char hexdatalenH8, hexdatalenL8;int len;int i;len = strlen ( str );if(len == 0){MessagePopup ("提示信息!","发送内容不能为空！");return 0;}        char senddata[len];for(int i = 0; i < len; ){char lstr,hstr = str[i];if(hstr == ' '){i++;continue;//学会使用此关键字}i++;if(i >= len)break;lstr = str[i];hexdata = ConvertHexChar ( hstr );lowhexdata = ConvertHexChar ( lstr );if((hexdata == 16)||(lowhexdata == 16))break;else       hexdata = hexdata * 16 + lowhexdata;i++;senddata[hexdatalen] = (char)hexdata;hexdatalen++;       }   ComWrt (comNum,senddata, hexdatalen);