Date: Wed, 21 Apr 2004 13:29:29 +0930 From: "Daniel O'Connor" <doconnor@gsoft.com.au> To: ticso@cicely.de Cc: freebsd-hackers@freebsd.org Subject: Re: Detecting 'floppy' like umass devices Message-ID: <200404211329.29681.doconnor@gsoft.com.au> In-Reply-To: <20040420085805.GA5279@cicely12.cicely.de> References: <200404192247.48015.doconnor@gsoft.com.au> <20040420085805.GA5279@cicely12.cicely.de>
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On Tue, 20 Apr 2004 18:28, Bernd Walter wrote: > > I am wondering if there is any way of telling if a given umass device is > > a floppy drive (or wants to look like one) - eg I have a USB FDD which > > I imagine should fall into the same basket. > > What do do you mean with "wants to look like one". > In which way does a floppy look different from other direct access > drives? > They all read and store direct access data. Partially to handle things like fdformat, and density selection, but also from a user point of view, ie it would be nice if it appeared as /dev/fdX. IMHO it's not obvious (and dangerous) to tell mtools that a: = /dev/da0 but that's what I have to do if I want to use my USB FDD with it. > > I note that you get wacky values from fdisk when you try and read > > partition table from them too.. > > > > On another note my USB floppy drive does 2k/sec in FreeBSD :( > > Sound like another instance of msdosfs does no clustering and drive > is too stupid to get speed without. > IIRC there were some work on this point, but I don't now the state. > Check the speed with dd and different blocksizes. This IS with dd :) I did a few tests.. Block Size | Speed ===========+=========== 0.5k | 2.2k/sec 1 k | 4.4k/sec 2 k | 8.0k/sec 4 k | 12.6k/sec 8 k | 17.7k/sec 16 k | 21.8k/sec 32 k | 23.9k/sec 64 k | 26.2k/sec Bleh :( > > I have a Dell Inspiron 8600 with a > > uhci0: <Intel 82801DB (ICH4) USB controller USB-A> port 0xbf80-0xbf9f irq > > 11 at device 29.0 on pci0 > > > > I have tried a USB flash card reader which gets ~500k/sec. > > If a drive doesn't preread blocks then each access has to wait for the > media - undoubly flash has a faster access time than floppies... Yeah, I just meant that "it's not my USB port" :) -- Daniel O'Connor software and network engineer for Genesis Software - http://www.gsoft.com.au "The nice thing about standards is that there are so many of them to choose from." -- Andrew Tanenbaum GPG Fingerprint - 9A8C 569F 685A D928 5140 AE4B 319B 41F4 5D17 FDD5
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