| | |
| | | public Boolean isThisProtocolHead(byte[] bs) throws Exception{ |
| | | if(bs == null){ |
| | | return null ; |
| | | }else if(bs.length >= (ProtocolConstantV206V202404.ctrlIndex - 1) |
| | | }else if(bs.length >= ProtocolConstantV206V202404.ctrlIndex |
| | | && bs[0] == ProtocolConstantV206V202404.P_Head_Byte){ |
| | | if(bs[2] == ProtocolConstantV206V202404.P_Head_Byte){ |
| | | return true ; |
| | | if(bs[3] == (byte)0x80 || bs[3] == (byte)0x81){ |
| | | return true ; |
| | | }else{ |
| | | return false ; |
| | | } |
| | | }else if((byte)(bs[2] & 0xF8) == ProtocolConstantV206V202404.P_Head_Byte){ |
| | | //如果控制域、地址域、用户数据域(应用层)的字节总数大于255,则通过扩展第二个开始字符0x68的低3位作为长L的高位扩展 |
| | | //0xF8二进制: 11111000 |
| | | return true ; |
| | | if(bs[3] == (byte)0x80 || bs[3] == (byte)0x81){ |
| | | return true ; |
| | | }else{ |
| | | return false ; |
| | | } |
| | | }else{ |
| | | return false ; |
| | | } |
| | |
| | | } |
| | | } |
| | | |
| | | /** |
| | | * 检查头 |
| | | * @param bs 上行字节数组 |
| | | * @throws Exception 异常 |
| | | */ |
| | | public void checkHead(byte[] bs) throws Exception{ |
| | | if(bs.length < ProtocolConstantV206V202404.lenHead2Code |
| | | || bs[0] != ProtocolConstantV206V202404.P_Head_Byte){ |
| | | throw new Exception("上行数据帧头不正确!") ; |
| | | }else{ |
| | | if(bs.length >= ProtocolConstantV206V202404.lenHead2Code){ |
| | | if(bs[2] != ProtocolConstantV206V202404.P_Head_Byte |
| | | && (byte)(bs[2] & 0xF8) != ProtocolConstantV206V202404.P_Head_Byte){ |
| | | throw new Exception("上行数据帧头不正确!") ; |
| | | } |
| | | }else{ |
| | | throw new Exception("上行数据帧头不正确!") ; |
| | | } |
| | | } |
| | | } |
| | | |
| | | /** |
| | | * 检查尾 |
| | |
| | | public byte createCtrl(byte dir, byte funcCode){ |
| | | byte b = dir;//DIR = 1(0x80),表示此帧报文是由终端发出的上行报文; |
| | | b = (byte)(b | funcCode) ; |
| | | //DIV = 1(0x40),表示此报文已被拆分为若干帧 |
| | | //FCB = 1(0x08),表示只发一次 |
| | | b = (byte)(b |0x08) ; |
| | | //DIV = 1(0x20),表示此报文已被拆分为若干帧 |
| | | //FCB = 1(0x10),表示只发一次 |
| | | b = (byte)(b |0x10) ; |
| | | //DIR = 0 下行,则功能码采用0 |
| | | return b ; |
| | | } |