void setup()
{
  Serial.begin( 115200 );

  char str[] = "AABBC DD EE F";

  char * pstr = str;
  uint8_t value;
  size_t count;

  while ( *pstr != '\0' && sscanf( pstr, "%2x%n", &value, &count ) == 1 )
  {
    Serial.println( value, HEX );
    pstr += count;
  }
}

void loop()
{
}