I have two DOS Superfloppy Images:
- 25 MB MS-DOS FAT16 probed C/H/S = 25/64/32 - 51200 total sectors
- 15 MB FreeDOS FAT12 probed C/H/S = 15/64/32 - 30720 total sectors
For MS-DOS the message is: Invalid system disk.
For FreeDOS I get message: FreeDOS with flashing cursor.
All previous versions of grub4dos e.g. grub4dos-0.4.4-2008-09-29 and older are booting fine my DOS Superfloppy Images and using in menu.lst on HD or USB-stick with NTFS or FAT format:
title FREEDOS Image find --set-root /BTFRDOS.img map /BTFRDOS.img (fd0) map --hook chainloader (fd0)+1 rootnoverify (fd0)
By using about 10 different versions of grub4dos grldr from
and thanks to the ChangeLog_GRUB4DOS.txt
I can say that the origin of the problem is most likely this fix:
The small 2880 KB DOS floppy Images do NOT have such boot problem with recent GRUB4DOS versions.
2008-09-30 fixed a big bug in set_bootdev causing extra rawread executed and the geometry messed up.