#include "../main/SystemInclude.h"

u8	isOldProtocol; 

__MB_Buf_TypeDef MBBuf;
/******************************************************************************/
u16 ModBusCRC(u8  *Data_Array , u8 DataLength)   //获取CRC
{
  u32 i, j;
  u16 CRCTemp;
  
  CRCTemp = 0xffff;
  for(i = 0; i<=DataLength; i++)
  {
    CRCTemp = CRCTemp ^ Data_Array[i];
    for(j=0; j<=7; j++)
    {
      if((CRCTemp & 0x0001)==0x0001) 
      {
        CRCTemp >>= 1;
        CRCTemp ^= 0xa001;
      }	
      else CRCTemp >>= 1;
    }
  }
  
  return  CRCTemp;
}

/******************************************************************************/
void ComputeTxdDataCRC(void)
{
  tempL.Word[0] = ModBusCRC(MBBuf.RxPointer, MBBuf.TxdLen-2);	//计算CRC
  MBBuf.RxPointer[MBBuf.TxdLen]   = tempL.Byte[1];
  MBBuf.RxPointer[MBBuf.TxdLen-1] = tempL.Byte[0]; 
  MBBuf.TxdLen++;
}

/******************************************************************************/
void ModBusErrorInfo(u8 ErrorCode)
{
  MBBuf.RxPointer[1] |= 0x80;				//返回执行错误
  MBBuf.RxPointer[2]  = 1;					//字节长度1	
  MBBuf.RxPointer[3]  = ErrorCode;	//返回详细错误代码：功能码错误 本设备不支持此功能
  MBBuf.TxdLen   = 5;
}

/******************************************************************************/
void ModBusReadMultiByte(void)
{  
  if(MBBuf.StartAddr < INT_PARAMETER_PROTOCOL)  UserReadDataProtocol();
  else                                          InternalReadParameterProtocol(); 
}

/******************************************************************************/
void ModBusWriteMultiByte(void)
{  
   if(MBBuf.StartAddr < INT_PARAMETER_PROTOCOL)  UserWriteDataProtocol();
   else   																			 InternalWriteParameterProtocol(); 
}

/******************************************************************************/
//ModBus数据处理
void ModBusDataProcessing(void)
{
  MBBuf.BusError = 0;
   switch(MBBuf.RxPointer[1])
  {
		case READ_HOLDING_REGISTERS: //0x03 读取保持寄存器---------------------------------------------
			MBBuf.StartAddr  = ((u16)MBBuf.RxPointer[2] << 8) | (u16)MBBuf.RxPointer[3]; 
			MBBuf.ByteNumber = ((u16)MBBuf.RxPointer[4] << 8) | (u16)MBBuf.RxPointer[5];
			
			if(MBBuf.ByteNumber > ENABLE_REG_MAX) {  
			  MBBuf.BusError = SLAVE_DEVICE_FAILURE;  
  			break; 
			}
			MBBuf.ByteNumber <<= 1;
			MBBuf.TxdLen       = MBBuf.ByteNumber;
			MBBuf.RxPointer[2] = MBBuf.TxdLen;//返回数据的字节数
			MBBuf.TxdLen      += 4;
			MBBuf.Index        = 3;
			ModBusReadMultiByte();//读操作
			break;
			
		case PRESET_SINGLE_REGISTER:	//0x06 写预置单寄存器---------------------------------------------
			MBBuf.StartAddr  = MBBuf.StartAddr  = ((u16)MBBuf.RxPointer[2] << 8) | (u16)MBBuf.RxPointer[3]; 
			MBBuf.EndAddr    = MBBuf.StartAddr + 1;
			MBBuf.TxdLen     = 7;
			MBBuf.ByteNumber = 2;
			MBBuf.Index      = 4;  // 接收到的数据有效起始
			ModBusWriteMultiByte();//写操作
			break;
			
		case PRESET_MULTIPLE_REGISTERS : //0x010 写预置多寄存器----------------------------------------
			//if(RxdIndex < 11) return;
			MBBuf.StartAddr  = ((u16)MBBuf.RxPointer[2] << 8) | (u16)MBBuf.RxPointer[3]; 
			MBBuf.ByteNumber = ((u16)MBBuf.RxPointer[4] << 8) | (u16)MBBuf.RxPointer[5];
			if(MBBuf.ByteNumber > ENABLE_REG_MAX) {  
			  MBBuf.BusError = SLAVE_DEVICE_FAILURE;   
			  break; 
			}
			MBBuf.EndAddr = MBBuf.StartAddr + MBBuf.ByteNumber;
			MBBuf.ByteNumber <<= 1;
			//准备返回数据
			MBBuf.RxPointer[1] = 0x10;	 
			MBBuf.TxdLen = 7;
			MBBuf.Index  = 7;
			ModBusWriteMultiByte();//写操作
			break;
			
		case ERROR_TEST : //0x08 错误诊断-------------------------------------------------------------
			if (MBBuf.RxPointer[0] != 0x00) //如果不是广播地址 则回复 否则静默
				break;
			
		default: //功能码未识别-----------------------------------------------------------------------
			MBBuf.BusError = ILLEGAL_FUNCTION;
			break;
  }
  
  if(MBBuf.BusError != 0) ModBusErrorInfo(MBBuf.BusError); 
	//广播地址 静默
  if(MBBuf.RxPointer[0] == 0x00) { 
	  MBBuf.TxdLen = 0; 
	  return;
	} 
	
  if(MBBuf.TxdLen == 0) return;
  ComputeTxdDataCRC();
  memmove( (char *)MBBuf.TxPointer, (char *)MBBuf.RxPointer, MBBuf.TxdLen);
}

/******************************************************************************/
//检测是否符合Modbus协议帧
u8 ModBusProtocolDetection(void)
{
  u16 CRCTempRX, CRCTempCX;
  
  MBBuf.TxdLen = 0;             
  if(MBBuf.RxdLen < 5) return 0; 
  // 判断地址是否错误
  if(MBBuf.RxPointer[0] == localAddress) goto DetecteNext;	
  else if(MBBuf.RxPointer[0] == 0)       goto DetecteNext;
	else return 0;		
	
DetecteNext:
  //tempL.Byte[1] = MBBuf.RxPointer[MBBuf.RxdLen-1];
  //tempL.Byte[0] = MBBuf.RxPointer[MBBuf.RxdLen-2];
  //CRCTempRX = tempL.Word[0];
  CRCTempRX = ((u16)MBBuf.RxPointer[MBBuf.RxdLen-1] << 8) | (u16)MBBuf.RxPointer[MBBuf.RxdLen-2];
  CRCTempCX = ModBusCRC(MBBuf.RxPointer, MBBuf.RxdLen-3);	// 计算CRC
  if(CRCTempRX != CRCTempCX) return 0;                    // CRC错误
  else                       return 1;
}

/******************************************************************************/
//Modbus变量指针处理
u8 ModbusVariablePointerProcess(void)
{
  if(MBBuf.ByteNumber >= MBBuf.DataByte) MBBuf.ByteNumber -= MBBuf.DataByte;
  else                     return 1;  
  
  if(MBBuf.ByteNumber < 2) return 1; 	
	
  MBBuf.DataByte  >>= 1;
  MBBuf.StartAddr  += MBBuf.DataByte;      
  
  return 0;
}

/******************************************************************************/
u8 ModbusVariablePointerDec(void)
{
  if(MBBuf.ByteNumber < MBBuf.DataByte + 2) {
    MBBuf.ByteNumber = 0;
    return 1;
  }
 
  MBBuf.ByteNumber -= MBBuf.DataByte;    
  MBBuf.DataByte  >>= 1;
  MBBuf.StartAddr  += MBBuf.DataByte;    
  return 0;
}

///******************************************************************************/
void CopyDataAndJudgeComplete(void)
{
  u32 I;
  for(I=1; I<= MBBuf.DataByte; I++) MBBuf.RxPointer[MBBuf.Index++] = tempL.Byte[MBBuf.DataByte-I];
  
  ModbusVariablePointerDec();
}