text: #ifndef __AUTH_H__
  #define __AUTH_H__
  
  #include "cards.h"
  
  // private variables
  
  // private functions
  static bool auth_compareToStoredCard(int i);
  
  // public functions
  static bool authCheckLocal()
  {
  	for (int i = 0; i < numOfCards; ++i)
  		if (auth_compareToStoredCard(i))
  			return true; 
  	return false;
  }
  
  // private implementation
  static bool auth_compareToStoredCard(int i)
  {
  	char* addr = (char*)pgm_read_word(cards + i);
  	return strncmp_P(readerCardNumber, addr, LENGTH) == 0;
  }
  
  #endif
  