Today was my first time to split and merge roms. I do it, with the new Sony MSX rom sets.
1.) Merge files (roms)
As example you need to merge 2x 16K files into one 32K file: Command line copy 500pext.rom /b + 500pdisk.rom /b 500pext.ic47 500pext.rom 16K 500pdisk.rom 16K 500pext.ic47 32K
2.) Split files (roms)
As example you need to split one 32K file into 2x 16K files: Start a file splitter tool like Splitfile (Freeware) Choose the 32K file 55pbios.rom Set the needed size > 16384 (16K) Split the 32K file Rename the new 2x 16K files 55pbios.ic42 55pbios.ic43 If you get a checksum error ( MESS Audition ), use no CRC in tool (without CRC you can catenate any arbitrary files).