Bought a retrode 2 2 weeks ago and try dumped a gameboy proto. now i compered it to the retail with a hex finder and its a couple of bits off. how can i see/know/find out what the difference is ?
Run the ROMs through a tile viewer like Tile Molester, look to see where the graphics are stored, and see if they look different between the two files. When checking the ROMs in something like Winhex, you might be able to find in-game text and compare. Other than that, the best way is probably to just play them side by side. If there are literally just a couple of bits different between the two ROMs, it might be really hard to find any non-graphical or non-text differences, assuming there are any actually perceivable differences.
You should look at the game checksum and header complement checksum first to see if you maybe introduced the differences during the dump through loose connections.
ROMCMP is a ROM comparison and validity checker written by Nicola Salmoria. It is included with MAME. It will compare two binary file images and tell you how closely they match each other. It will also tell you if there are potential problems with the ROM image, like stuck bits, duplicate data, etc. There's a Macintosh version, too.
