Inside Amiibo Touch & Play: Nintendo Classics Highlights (aka Amiibo Tap: Nintendo's Greatest Bits) there is a file called VcRomDataUs.szs which contains the ROMs for the game. Most are the standard Nintendo style NES ROMs (not iNES headered) and SNES SFROMs (different header + PCM audio) but there is one QD file in there for Super Mario Bros 2. Opening it up in a hex editor shows that apart from the first 30 bytes, it looks pretty similar to the QD files on the NES Classic (so checksums after every block) but on closer look it seems like there's additional data after side 1. Initially I thought this was an incorrectly formatted side 2 but Super Mario Bros 2 is only single sided.
Obviously this means that fdstool reports that it's not a valid QD file.
To make this QD file work with fdstool I have basically hacked up the QD file with just-about-educated guesses. First I removed the new 30 byte pre-header from the start of the file. I then stripped everything from the QD file after the end of side 1. Now when I run this through fdstool, it reports CRC errors throughout the file but seems to spit out a correct FDS file at the end.
fdstool works great for what it was created for (converting NES Classics QD to FDS) but I thought the above info might be useful for anybody else trying to convert this specific file.
Inside Amiibo Touch & Play: Nintendo Classics Highlights (aka Amiibo Tap: Nintendo's Greatest Bits) there is a file called VcRomDataUs.szs which contains the ROMs for the game. Most are the standard Nintendo style NES ROMs (not iNES headered) and SNES SFROMs (different header + PCM audio) but there is one QD file in there for Super Mario Bros 2. Opening it up in a hex editor shows that apart from the first 30 bytes, it looks pretty similar to the QD files on the NES Classic (so checksums after every block) but on closer look it seems like there's additional data after side 1. Initially I thought this was an incorrectly formatted side 2 but Super Mario Bros 2 is only single sided.
Obviously this means that fdstool reports that it's not a valid QD file.
To make this QD file work with fdstool I have basically hacked up the QD file with just-about-educated guesses. First I removed the new 30 byte pre-header from the start of the file. I then stripped everything from the QD file after the end of side 1. Now when I run this through fdstool, it reports CRC errors throughout the file but seems to spit out a correct FDS file at the end.
fdstool works great for what it was created for (converting NES Classics QD to FDS) but I thought the above info might be useful for anybody else trying to convert this specific file.