Ok, let's try it

Current limitations:
- HxC need to be installed as drive A&B (this is the default HxC setting), autodetection and mixed HxC and real floppy drive mode will come later.
- only FAT32 formatted SDCard is supported (the latest HxC firmware added the FAT12/FAT16 support), others coming later.
- card can be formatted without MBR, or if MBR exists then first partition entry is used (as the HxC)
- EP64 is currently not supported because the video memory is too slow to run WD177x routines

Keys:
Joy Up/Down: file cursor
Joy Left/Right: Prev/Next page
A/B: set the active drive
Enter: enter directory, or set the selected file to the current drive
F1: Start the disk in current drive: firstly try to execute EXDOS.INI then load START file. If these are not found then jump to ENTERPRISE logo screen.
STOP: exit program, jump to the ENTERPRISE logo screen.
In directory list the total meaningless . entry has been replaced with \ so now it's easy to go back to the root directory from any sub-sub.. directory.
The default drive is asked from EXDOS at the start.
The future ROM version will be the most comfortable version.
But now for the loadable version I suggest keeping the HxC manager disk in drive A: and replacing disk images in drive B:
The attached HFE disk image prepared with EXDOS.INI for this method.
Note: this is first public beta version, don't store any important data on the SDCard!
But I hope no any critical bug
