MFRC522_Init();

    /*--------------- Loop embarcado ---------------*/

    while (1)

    {

        UART_Write(0x11);

        {

        if( MFRC522_isCard( TagType ) )

            UART_Write(0xCC);

            if( MFRC522_ReadCardSerial( &UID ) )

            { 

                //sprintf(texto,"%lu",codigo_rfid);// lo pasa a unsigned long

                //LongIntToHex(codigo_rfid,texto);

                UART_Write(0xAA);

            }

        }

//conecci�n de modulo RFID   usando SPI pot software

#include "SPI-Flash.h"

//MF522 Command word

#define PCD_IDLE              0x00               //NO action; Cancel the current command

#define PCD_AUTHENT           0x0E               //Authentication Key

#define PCD_RECEIVE           0x08               //Receive Data

#define PCD_TRANSMIT          0x04               //Transmit data

#define PCD_TRANSCEIVE        0x0C               //Transmit and receive data,

#define PCD_RESETPHASE        0x0F               //Reset

#define PCD_CALCCRC           0x03               //CRC Calculate

// Mifare_One card command word

#define PICC_REQIDL          0x26               // find the antenna area does not enter hibernation

#define PICC_REQALL          0x52               // find all the cards antenna area

#define PICC_ANTICOLL        0x93               // anti-collision

#define PICC_SElECTTAG       0x93               // election card

#define PICC_AUTHENT1A       0x60               // authentication key A

#define PICC_AUTHENT1B       0x61               // authentication key B

#define PICC_READ            0x30               // Read Block

#define PICC_WRITE           0xA0               // write block

#define PICC_DECREMENT       0xC0               // debit

#define PICC_INCREMENT       0xC1               // recharge

#define PICC_RESTORE         0xC2               // transfer block data to the buffer

#define PICC_TRANSFER        0xB0               // save the data in the buffer

#define PICC_HALT            0x50               // Sleep

//And MF522 The error code is returned when communication

#define MI_OK                 0

#define MI_NOTAGERR           1

#define MI_ERR                2

//------------------MFRC522 Register---------------

//Page 0:Command and Status

#define     RESERVED00            0x00

#define     COMMANDREG            0x01

#define     COMMIENREG            0x02

#define     DIVLENREG             0x03

#define     COMMIRQREG            0x04

#define     DIVIRQREG             0x05

#define     ERRORREG              0x06

#define     STATUS1REG            0x07

#define     STATUS2REG            0x08

#define     FIFODATAREG           0x09

#define     FIFOLEVELREG          0x0A

#define     WATERLEVELREG         0x0B

#define     CONTROLREG            0x0C

#define     BITFRAMINGREG         0x0D

#define     COLLREG               0x0E

#define     RESERVED01            0x0F

//PAGE 1:Command

#define     RESERVED10            0x10

#define     MODEREG               0x11

#define     TXMODEREG             0x12

#define     RXMODEREG             0x13

#define     TXCONTROLREG          0x14

#define     TXAUTOREG             0x15

#define     TXSELREG              0x16

#define     RXSELREG              0x17

#define     RXTHRESHOLDREG        0x18

#define     DEMODREG              0x19

#define     RESERVED11            0x1A

#define     RESERVED12            0x1B

#define     MIFAREREG             0x1C

#define     RESERVED13            0x1D

#define     RESERVED14            0x1E

#define     SERIALSPEEDREG        0x1F

//PAGE 2:CFG

#define     RESERVED20            0x20

#define     CRCRESULTREGM         0x21

#define     CRCRESULTREGL         0x22

#define     RESERVED21            0x23

#define     MODWIDTHREG           0x24

#define     RESERVED22            0x25

#define     RFCFGREG              0x26

#define     GSNREG                0x27

#define     CWGSPREG              0x28

#define     MODGSPREG             0x29

#define     TMODEREG              0x2A

#define     TPRESCALERREG         0x2B

#define     TRELOADREGH           0x2C

#define     TRELOADREGL           0x2D

#define     TCOUNTERVALUEREGH     0x2E

#define     TCOUNTERVALUEREGL     0x2F

//PAGE 3:TEST REGISTER

#define     RESERVED30            0x30

#define     TESTSEL1REG           0x31

#define     TESTSEL2REG           0x32

#define     TESTPINENREG          0x33

#define     TESTPINVALUEREG       0x34

#define     TESTBUSREG            0x35

#define     AUTOTESTREG           0x36

#define     VERSIONREG            0x37

#define     ANALOGTESTREG         0x38

#define     TESTDAC1REG           0x39

#define     TESTDAC2REG           0x3A

#define     TESTADCREG            0x3B

#define     RESERVED31            0x3C

#define     RESERVED32            0x3D

#define     RESERVED33            0x3E

#define     RESERVED34            0x3F

static void MFRC522_Wr( char addr, char value )

{

        MFRC522_CS = 0;

        SPI_Write( ( addr << 1 ) & 0x7E );

        SPI_Write( value );

        MFRC522_CS = 1;

}

static uint8_t MFRC522_Rd( char addr )

{

        uint8_t value;

        MFRC522_CS = 0;

        SPI_Write( (( addr << 1 ) & 0x7E) | 0x80 );

        value = SPI_Read();

        MFRC522_CS = 1;

        return value;

}

static void MFRC522_Clear_Bit( char addr, char mask )

{

     MFRC522_Wr( addr, MFRC522_Rd( addr ) & (~mask) );

}

static void MFRC522_Set_Bit( char addr, char mask )

{

     MFRC522_Wr( addr, MFRC522_Rd( addr ) | mask );

}

void MFRC522_Reset()

{

        MFRC522_Wr( COMMANDREG, PCD_RESETPHASE );

}

void MFRC522_AntennaOn()

{

 MFRC522_Set_Bit( TXCONTROLREG, 0x03 );

}

void MFRC522_AntennaOff()

{

 MFRC522_Clear_Bit( TXCONTROLREG, 0x03 );

}

void MFRC522_Init()

{

     MFRC522_CS_Direction = 0;

     MFRC522_Rst_Direction = 0;

     MFRC522_CS = 1;

     MFRC522_Rst = 1;

     MFRC522_Reset();

     MFRC522_Wr( TMODEREG, 0x8D );      //Tauto=1; f(Timer) = 6.78MHz/TPreScaler

     MFRC522_Wr( TPRESCALERREG, 0x3E ); //TModeReg[3..0] + TPrescalerReg

     MFRC522_Wr( TRELOADREGL, 30 );

     MFRC522_Wr( TRELOADREGH, 0 );

     MFRC522_Wr( TXAUTOREG, 0x40 );

     MFRC522_Wr( MODEREG, 0x3D );

    //  MFRC522_Wr( TMODEREG, 0x8D );      //Tauto=1; f(Timer) = 6.78MHz/TPreScaler

    //  MFRC522_Wr( TPRESCALERREG, 0x3E ); //TModeReg[3..0] + TPrescalerReg

    //  MFRC522_Wr( TRELOADREGL, 30 );

    //  MFRC522_Wr( TRELOADREGH, 0 );

    //  MFRC522_Wr( TXAUTOREG, 0x40 );    //100%ASK

    //  MFRC522_Wr( MODEREG, 0x3D );      // CRC valor inicial de 0x6363

     //MFRC522_Clear_Bit( STATUS2REG, 0x08 );//MFCrypto1On=0

     //MFRC522_Wr( RXSELREG, 0x86 );      //RxWait = RxSelReg[5..0]

     //MFRC522_Wr( RFCFGREG, 0x7F );     //RxGain = 48dB

    UART_Write(0x99);

     MFRC522_AntennaOn();

    MFRC522_Wr( RFCFGREG, 0x50 );

}

char MFRC522_ToCard( char command, char *sendData, char sendLen, char *backData, unsigned *backLen )

{

  char _status = MI_ERR;

  char irqEn = 0x00;

  char waitIRq = 0x00;

  char lastBits;

  char n;

  unsigned i;

  switch (command)

  {

    case PCD_AUTHENT:       //Certification cards close

    {

      irqEn = 0x12;

      waitIRq = 0x10;

      break;

    }

    case PCD_TRANSCEIVE:    //Transmit FIFO data

    {

      irqEn = 0x77;

      waitIRq = 0x30;

      break;

    }

    default:

      break;

  }

  MFRC522_Wr( COMMIENREG, irqEn | 0x80 );

  MFRC522_Clear_Bit( COMMIRQREG, 0x80 );

  MFRC522_Set_Bit( FIFOLEVELREG, 0x80 );

  MFRC522_Wr( COMMANDREG, PCD_IDLE );

  //Writing data to the FIFO

  for ( i=0; i < sendLen; i++ )

  {

    MFRC522_Wr( FIFODATAREG, sendData[i] );

  }

  //Execute the command

  MFRC522_Wr( COMMANDREG, command );

  if (command == PCD_TRANSCEIVE )

  {

    MFRC522_Set_Bit( BITFRAMINGREG, 0x80 ); //StartSend=1,transmission of data starts

  }

    //UART_Write(MFRC522_Rd(FIFODATAREG));

  //Waiting to receive data to complete

  //i according to the clock frequency adjustment, the operator M1 card maximum waiting time 25ms???

  i = 25;

  do

  {

    __delay_ms(1);

    //CommIrqReg[7..0]

    //Set1 TxIRq RxIRq IdleIRq HiAlerIRq LoAlertIRq ErrIRq TimerIRq

    n = MFRC522_Rd( COMMIRQREG );

    i--;

  }

  while ( i && !(n & 0x01) && !( n & waitIRq ) );

  MFRC522_Clear_Bit( BITFRAMINGREG, 0x80 );    //StartSend=0

  UART_Write(MFRC522_Rd(RFCFGREG));

 UART_Write(0x78);

  UART_Write(MFRC522_Rd(STATUS2REG));

  UART_Write(0x22);

  UART_Write(i);

  UART_Write(0x33);

  UART_Write(n);

  if (i != 0)

  {

    if (!(MFRC522_Rd(ERRORREG) & 0x1B)) //BufferOvfl Collerr CRCErr ProtecolErr

    {

      _status = MI_OK;

      if (n & irqEn & 0x01)

      {

        _status = MI_NOTAGERR; //??

      }

      if (command == PCD_TRANSCEIVE)

      {

        n = MFRC522_Rd(FIFOLEVELREG);

        lastBits = MFRC522_Rd(CONTROLREG) & 0x07;

        if (lastBits)

        {

          *backLen = (n - 1) * 8 + lastBits;

        }

        else

        {

          *backLen = n * 8;

        }

        if (n == 0)

        {

          n = 1;

        }

        if (n > 16)

        {

          n = 16;

        }

        //Reading the received data in FIFO

        for (i = 0; i < n; i++)

        {

          backData[i] = MFRC522_Rd(FIFODATAREG);

        }

        backData[i] = 0;

      }

    }

    else

    {

      _status = MI_ERR;

    }

  }

  //MFRC522_Set_Bit( CONTROLREG, 0x80 );

  //MFRC522_Wr( COMMANDREG, PCD_IDLE );

  return _status;

}

char MFRC522_Request(char reqMode, char *TagType)

{

  char _status;

  unsigned backBits; //The received data bits

  MFRC522_Wr(BITFRAMINGREG, 0x07); //TxLastBists = BitFramingReg[2..0]   ???

  TagType[0] = reqMode;

  _status = MFRC522_ToCard(PCD_TRANSCEIVE, TagType, 1, TagType, &backBits);

  if ((_status != MI_OK) || (backBits != 0x10))

  {

    _status = MI_ERR;

  }

  return _status;

}

void MFRC522_CRC(char *dataIn, char length, char *dataOut)

{

  char i, n;

  MFRC522_Clear_Bit(DIVIRQREG, 0x04);

  MFRC522_Set_Bit(FIFOLEVELREG, 0x80);

  //Escreve dados no FIFO

  for (i = 0; i < length; i++)

  {

    MFRC522_Wr(FIFODATAREG, *dataIn++);

  }

  MFRC522_Wr(COMMANDREG, PCD_CALCCRC);

  i = 0xFF;

  //Espera a finaliza��o do Calculo do CRC

  do

  {

    n = MFRC522_Rd(DIVIRQREG);

    i--;

  } while (i && !(n & 0x04)); //CRCIrq = 1

  dataOut[0] = MFRC522_Rd(CRCRESULTREGL);

  dataOut[1] = MFRC522_Rd(CRCRESULTREGM);

}

char MFRC522_SelectTag(char *serNum)

{

  char i;

  char _status;

  char size;

  unsigned recvBits;

  char buffer[9];

  //MFRC522_Clear_Bit( STATUS2REG, 0x08 );   //MFCrypto1On=0

  buffer[0] = PICC_SElECTTAG;

  buffer[1] = 0x70;

  for (i = 2; i < 7; i++)

  {

    buffer[i] = *serNum++;

  }

  MFRC522_CRC(buffer, 7, &buffer[7]);

  _status = MFRC522_ToCard(PCD_TRANSCEIVE, buffer, 9, buffer, &recvBits);

  if ((_status == MI_OK) && (recvBits == 0x18))

  {

    size = buffer[0];

  }

  else

  {

    size = 0;

  }

  return size;

}

//hibernation

void MFRC522_Halt()

{

  unsigned unLen;

  char buff[4];

  buff[0] = PICC_HALT;

  buff[1] = 0;

  MFRC522_CRC( buff, 2, &buff[2] );

  MFRC522_Clear_Bit( STATUS2REG, 0x80 );

  MFRC522_ToCard( PCD_TRANSCEIVE, buff, 4, buff, &unLen );

  MFRC522_Clear_Bit( STATUS2REG, 0x08 );

}

char MFRC522_Auth( char authMode, char BlockAddr, char *Sectorkey, char *serNum )

{

  char _status;

  unsigned recvBits;

  char i;

  char buff[12];

  //Verify the command block address + sector + password + card serial number

  buff[0] = authMode;

  buff[1] = BlockAddr;

  for ( i = 2; i < 8; i++ )

  {

    buff[i] = Sectorkey[i-2];

  }

  for ( i = 8; i < 12; i++ )

  {

    buff[i] = serNum[i-8];

  }

  _status = MFRC522_ToCard( PCD_AUTHENT, buff, 12, buff, &recvBits );

  if ( ( _status != MI_OK ) || !( MFRC522_Rd( STATUS2REG ) & 0x08 ) )

  {

    _status = MI_ERR;

  }

  return _status;

}

char MFRC522_Write( char blockAddr, char *writeData )

{

  char _status;

  unsigned recvBits;

  char i;

  char buff[18];

  buff[0] = PICC_WRITE;

  buff[1] = blockAddr;

  MFRC522_CRC( buff, 2, &buff[2] );

  _status = MFRC522_ToCard( PCD_TRANSCEIVE, buff, 4, buff, &recvBits );

  if ( (_status != MI_OK) || (recvBits != 4) || ( (buff[0] & 0x0F) != 0x0A) )

  {

    _status = MI_ERR;

  }

  if (_status == MI_OK)

  {

    for ( i = 0; i < 16; i++ )                //Data to the FIFO write 16Byte

    {

      buff[i] = writeData[i];

    }

    MFRC522_CRC( buff, 16, &buff[16] );

    _status = MFRC522_ToCard( PCD_TRANSCEIVE, buff, 18, buff, &recvBits );

    if ( (_status != MI_OK) || (recvBits != 4) || ( (buff[0] & 0x0F) != 0x0A ) )

    {

      _status = MI_ERR;

    }

  }

  return _status;

}

char MFRC522_Read( char blockAddr, char *recvData )

{

  char _status;

  unsigned unLen;

  recvData[0] = PICC_READ;

  recvData[1] = blockAddr;

  MFRC522_CRC( recvData, 2, &recvData[2] );

  _status = MFRC522_ToCard( PCD_TRANSCEIVE, recvData, 4, recvData, &unLen );

  if ( (_status != MI_OK) || (unLen != 0x90) )

  {

    _status = MI_ERR;

  }

  return _status;

}

char MFRC522_AntiColl( char *serNum )

{

  char _status;

  char i;

  char serNumCheck = 0;

  unsigned unLen;

  MFRC522_Wr( BITFRAMINGREG, 0x00 );                //TxLastBists = BitFramingReg[2..0]

  serNum[0] = PICC_ANTICOLL;

  serNum[1] = 0x20;

  MFRC522_Clear_Bit( STATUS2REG, 0x08 );

  _status = MFRC522_ToCard( PCD_TRANSCEIVE, serNum, 2, serNum, &unLen );

  if (_status == MI_OK)

  {

    for ( i=0; i < 4; i++ )

    {

      serNumCheck ^= serNum[i];

    }

    if ( serNumCheck != serNum[4] )

    {

      _status = MI_ERR;

    }

  }

  return _status;

}

//0x0044 = Mifare_UltraLight

//0x0004 = Mifare_One (S50)

//0x0002 = Mifare_One (S70)

//0x0008 = Mifare_Pro (X)

//0x0344 = Mifare_DESFire

char MFRC522_isCard( char *TagType )

{

    if (MFRC522_Request( PICC_REQALL, TagType ) == MI_OK)

        return 1;

    else

        return 0;

}

char MFRC522_ReadCardSerial( char *str )

{

char _status;

 _status = MFRC522_AntiColl( str );

 str[5] = 0;

 if (_status == MI_OK)

  return 1;

 else

  return 0;

}