#include<reg52.h>
#include<rc500.h>

idata struct TranSciveBuffer{uchar MfCommand;
                             uchar MfLength;
                             uchar MfData[19];
                            };

char PcdComTransceive(struct TranSciveBuffer *pi)
{
   bit recebyte=0;
   char status;
   uchar irqEn=0x00;
   uchar waitFor=0x00;
   uchar lastBits;
   uchar n;
   uint i;
   switch(pi->MfCommand)
   {
      case PCD_IDLE:
         irqEn = 0x00;
         waitFor = 0x00;
         break;
      case PCD_WRITEE2:
         irqEn = 0x11;
         waitFor = 0x10;
         break;
      case PCD_READE2:
         irqEn = 0x07;
         waitFor = 0x04;
         recebyte=1;
         break;
      case PCD_LOADCONFIG:
      case PCD_LOADKEYE2:
      case PCD_AUTHENT1:
         irqEn = 0x05;
         waitFor = 0x04;
         break;
      case PCD_CALCCRC:
         irqEn = 0x11;
         waitFor = 0x10;
         break;
      case PCD_AUTHENT2:
         irqEn = 0x04;
         waitFor = 0x04;
         break;
      case PCD_RECEIVE:
         irqEn = 0x06;
         waitFor = 0x04;
         recebyte=1;
         break;
      case PCD_LOADKEY:
         irqEn = 0x05;
         waitFor = 0x04;
         break;
      case PCD_TRANSMIT:
         irqEn = 0x05;
         waitFor = 0x04;
         break;
      case PCD_TRANSCEIVE:
         irqEn = 0x3D;
         waitFor = 0x04;
         recebyte=1;
         break;
      default:
         pi->MfCommand=MI_UNKNOWN_COMMAND;
         break;
   }
   if(pi->MfCommand!=MI_UNKNOWN_COMMAND)
   {
      WriteRC(RegPage,0x00);
      WriteRC(RegInterruptEn,0x7F);
      WriteRC(RegInterruptRq,0x7F);
      WriteRC(RegCommand,PCD_IDLE);
      SetBitMask(RegControl,0x01);
      WriteRC(RegInterruptEn,irqEn|0x80);
      for(i=0;i<pi->MfLength;i++)
      {
         WriteRC(RegFIFOData,pi->MfData[i]);
      }
      WriteRC(RegCommand,pi->MfCommand);
      i=0x2000;
      do
      {
         n=ReadRC(RegInterruptRq);
         i--;
      }
      while((i!=0)&&!(n&irqEn&0x20)&&!(n&waitFor));
      status=MI_COM_ERR;
      if((i!=0)&&!(n&irqEn&0x20))
      {
         if(!(ReadRC(RegErrorFlag)&0x17))
         {
            status=MI_OK;
            if(recebyte)
            {
              	n=ReadRC(RegFIFOLength);
              	lastBits=ReadRC(RegSecondaryStatus)&0x07;
                if(lastBits)
                {
                   pi->MfLength=(n-1)*8+lastBits;
                }
                else
                {
                   pi->MfLength=n*8;
                }
                if(n==0)
                {
                   n=1;
                }
                for(i=0;i<n;i++)
                {
                      pi->MfData[i]=ReadRC(RegFIFOData);
                }
            }
         }
      }
      else if(n&irqEn&0x20)
      {
          status=MI_NOTAGERR;
      }
      else
      {
          status=MI_COM_ERR;
      }
      WriteRC(RegInterruptEn,0x7F);
      WriteRC(RegInterruptRq,0x7F);
   }
   return status;
}