From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1KfvUN-0007ha-H5 for qemu-devel@nongnu.org; Wed, 17 Sep 2008 07:46:31 -0400 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1KfvUL-0007gx-Sk for qemu-devel@nongnu.org; Wed, 17 Sep 2008 07:46:30 -0400 Received: from [199.232.76.173] (port=41020 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1KfvUL-0007gc-JP for qemu-devel@nongnu.org; Wed, 17 Sep 2008 07:46:29 -0400 Received: from mailout.artfiles.de ([80.252.97.80]:46225) by monty-python.gnu.org with esmtps (TLS-1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.60) (envelope-from ) id 1KfvUK-00017o-WA for qemu-devel@nongnu.org; Wed, 17 Sep 2008 07:46:29 -0400 Received: from [87.185.154.200] (helo=bttr-software.de) auth=rr@bttr-software.de by mailout.artfiles.de with esmtpa (Exim 4.69) id 1KfvUB-0005Iy-Rd for qemu-devel@nongnu.org; Wed, 17 Sep 2008 13:46:20 +0200 Message-ID: <48D0EE05.574440C9@bttr-software.de> Date: Wed, 17 Sep 2008 13:46:13 +0200 From: Robert Riebisch MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Subject: [Qemu-devel] Problem with `change' monitor command Reply-To: qemu-devel@nongnu.org List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Hi! I'm using QEMU 0.9.1 and SVN on Win32 to emulate an x86 PC environment. With `change floppy0 foo.img' I'm able to use another floppy image on the fly, but this will only work, if the new floppy image is of the same size as the old one. Switching from, e.g., 1.44M to 2.88M is not recognized by the guest OS. Even rebooting the VM doesn't help, because CMOS value 0x10 ("Floppy Drive Type") won't be adjusted. (http://www.brl.ntt.co.jp/people/takehiko/interrupt/CMOS.LST.txt) This is also a big problem when you omit "-fda bar.img" from the command line. You can still change the image file in QEMU monitor, but guest OS (here: DOS) will never recognize it, because CMOS value 0x10 still holds "0" (= "none" for floppy0 and floppy1). Btw: It would be more consistently to also change command-line option "-fda" to "-floppy0". For demonstration I quickly wrote a minimal DOS tool using free Turbo Pascal 5.5 to decode this value. Just tell me, if anyone is interested in the binary and source code (very simple). I could also provide a bootable disk image (FreeDOS + my tool). Robert Riebisch -- BTTR Software http://www.bttr-software.de/