Date: Thu, 03 Jul 1997 15:32:37 +0100 From: Matthias Paul Subject: Re: Win95 and OpenDOS: an experiement. To: opendos AT delorie DOT com Reply-to: Matthias DOT Paul AT post DOT rwth-aachen DOT de Message-id: <1971BD508C4@reze-1.rz.rwth-aachen.de> Organization: Rechenzentrum RWTH Aachen Content-transfer-encoding: 7BIT Precedence: bulk Hi. While updating and enhancing COD's IBMBIO.COM, I also tried to make it a bit more compatible with MS Windows95. Though we have e.g. LOADER (checked this with a version from DR/Novell and with CCI's version from Multiuser DOS) running Novell DOS, OpenDOS, and Windows95/MS-DOS/PC-DOS piecefully together on the same hard disk partition (using the undocumented SYS /DR:ext), I thought it was great, if we could force Windows95 start menu to load OpenDOS via the "'old' DOS version" item, where it normally complains about "wrong version of MS-DOS". I tracked this problem down to Windows peeking a few bytes in IBMBIO.COM to retrieve it's version. After patching our IBMBIO.COM to have the same magic numbers at the same places, Windows actually lauched our IBMBIO.COM. Unfortunately, our IBMBIO.COM crashed soon after this. I'm sure this is manageable, since - at this moment - we don't need any Windows code any more (Windows has just played being a 'boot sector'). However, there must be some difference (register values, loading position of the code, etc.) compared to our own boot sector code. To avoid length debugging sessions, does anybody having ad-hoc knowlegde of these details? BTW, does anybody know the details on the differences between DRVSPACE from MS-DOS 7 and DRVSPACE from MS-DOS 6.22 (internal version numbers etc.). My updated IBMBIO.COM now also works with DRVSPACE from MS-DOS 6.22, but refuses to load DRVSPACE from MS-DOS 7, although MS-DOS 6.22 does load MS-DOS 7' DRVSPACE... Any DRVSPACE expert having in-deep knowlegde in this area? Matthias -------------------------------------------------------------------- Snail mail: Matthias Paul, Ubierstrasse 28, D-50321 Bruehl, Germany New eMail : Web : URL: http://www.rhrz.uni-bonn.de/~uzs180/mpdokeng.html --------------------------------------------------------------------