public int handler(int offset) {
            /*
             Protection (slammasters):
	
             The code does a checksum on an area of memory. I have no idea what
             this memory is. I have no idea whether it is RAM based or hard-wired.
	
             The code adds the low bytes of 0x415 words starting at 0xf0e000
	
             The result is ANDed with 0xffffff00 and then multiplied by 2. This
             value is stored and used throughout the game to calculate the
             base offset of the source scroll ROM data.
	
             The sum of the low bytes of the first 0x415 words starting at
             address 0xf0e000 should be 0x1df00
	
             In the absence of any real data, a rough calculation will do the
             job.
             */

            if (offset < (0x411 * 2)) {
                /*
                 0x411 * 0x76 = 0x1dfd6  (which is close enough)
                 */
                return 0x76;
            } else {
                return 0;
            }
        }