Hi Eric, this might be related to / the same as [1]. If it is, it should be fixed by [2]. Can you test with a current kernel?
[1]: https://github.com/FDOS/kernel/issues/144 [2]: https://github.com/FDOS/kernel/commit/c08313ab62ed236fc9a11f1c558cc335b93de30c Bernd > Am 01.06.2025 um 11:25 schrieb Eric Auer via Freedos-devel > <freedos-devel@lists.sourceforge.net>: > > > Hi! Zbigniew found out that with FreeDOS, > you first have to do something else with a > floppy before you can use it via INT 25/26. > > This could be for example opening a directory, > int 21.32 (get DPB) or switching to the drive > or changing the directory (CWD, CDS), I think. > > Those call media_check() or, in the case of > int 21.32, even do a full sequence of get_dpb, > flush_buffers ("unchecked") and media_check. > > With MS DOS, int 25/26 works even if you have > not touched the floppy in any way since boot. > > It seems that FreeDOS tries to init drive > status for all drives at boot, but does not > do enough for floppies? (I do not remember > if MS DOS would spin up floppies at boot?) > > Either way, in FreeDOS, the issue is: > > If you have not done anything to get in > touch with your current floppy since boot, > trying to use int 25/26 as the FIRST thing > to access it will mean that the get_dpb() > call in dskxfer in blockio.c will fail and > int 25/26 will return an error. > > With MS DOS 6.22, the interesting observation > of Zbigniew was that ax got set to 0201 but > carry did not get set, so he ignored ax and > indeed MS-DOS correctly accesses the floppy > even if you have not touched it before. > > This might mean that our DPB / CDS init code > does not behave as intended or that we might > want int 25 / 26 to check whether a floppy > has been inserted or changed before giving > up after a failed get_dpb() call? > > Regards, Eric > > PS: There might be an interaction with the > DJ mechanism, too. We have not checked that. > > > > _______________________________________________ > Freedos-devel mailing list > Freedos-devel@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/freedos-devel _______________________________________________ Freedos-devel mailing list Freedos-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/freedos-devel
