File content as of revision 21:00c94aeb533e:

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#include "RomId.hpp"


//--------------------------------------------------------------------------
// Calculate the CRC8 of the byte value provided with the current 
// global 'crc8' value. 
// Returns current global crc8 value
//
std::uint8_t RomId::calculateCRC8(std::uint8_t crc8, std::uint8_t data)
{
   int i; 

   // See Application Note 27
   crc8 = crc8 ^ data;
   for (i = 0; i < 8; ++i)
   {
      if (crc8 & 1)
         crc8 = (crc8 >> 1) ^ 0x8c;
      else
         crc8 = (crc8 >> 1);
   }

   return crc8;
}

std::uint8_t RomId::calculateCRC8(const std::uint8_t * data, std::size_t data_len, std::uint8_t crc)
{
  for (std::size_t i = 0; i < data_len; i++)
    crc = calculateCRC8(crc, data[i]);
  return crc;
}