VGMPlay requires MSX-DOS2. The DOS2 features we depend on are the mapper support routines, as well as the DOS2 disk I/O function calls and abort handling.
This issue is about supporting MSX-DOS1 as well.
I’m not likely to work on this, because:
- DOS2 / Nextor is pretty widespread nowadays with the many mass storage interfaces available.
- VGM files are inconvenient to use on floppy disks due to their size and absence of directories.
- This will cost time and memory which I can better spend on other features.
Regarding mapper support routines; recently a 25-year old Japanese utility was uncovered: MU Mapper Support Routines for DOS1. This removes the need to implement DOS1 mapper routines in VGMPlay, leaving just the DOS2 disk I/O function calls. For the latter, maybe a small compatibility layer could be written which translates DOS2 calls to DOS1 calls. It would be even nicer if this could be done in a generic program external to VGMPlay, just like MU.