void enc624j600UpdateMacConfig(NetInterface *interface)
{
   uint16_t duplexMode;

   //Determine the new duplex mode by reading the PHYDPX bit
   duplexMode = enc624j600ReadReg(interface, ENC624J600_REG_ESTAT) & ESTAT_PHYDPX;

   //Full-duplex mode?
   if(duplexMode)
   {
      //Configure the FULDPX bit to match the current duplex mode
      enc624j600WriteReg(interface, ENC624J600_REG_MACON2, MACON2_DEFER |
         MACON2_PADCFG2 | MACON2_PADCFG0 | MACON2_TXCRCEN | MACON2_R1 | MACON2_FULDPX);
      //Configure the Back-to-Back Inter-Packet Gap register
      enc624j600WriteReg(interface, ENC624J600_REG_MABBIPG, 0x15);
   }
   //Half-duplex mode?
   else
   {
      //Configure the FULDPX bit to match the current duplex mode
      enc624j600WriteReg(interface, ENC624J600_REG_MACON2, MACON2_DEFER |
         MACON2_PADCFG2 | MACON2_PADCFG0 | MACON2_TXCRCEN | MACON2_R1);
      //Configure the Back-to-Back Inter-Packet Gap register
      enc624j600WriteReg(interface, ENC624J600_REG_MABBIPG, 0x12);
   }
}
The product receives input or data, but it does
        not validate or incorrectly validates that the input has the
        properties that are required to process the data safely and
        correctly.