dannie@coplex.uucp (Dannie Gregoire) (02/16/91)
I have tried several times to get some answers to some hardware questions but have recieved NO replies. I would assume by the name of this group that there are at least a few hardware hacks out there. If so, PLEASE answer me this..... What are the hardware differences between 760K and 1.44M 3.5" floppy drives??? The limited information that I have tells me that there is no difference, but some experimentation tells me otherwise. If you know the answer to this, PLEASE respond. Thank You. +-------------------------------------------------------------------------+ | Dannie J. Gregoire \\\\//// dannie@coplex | | Copper Electronics Inc. ////\\\\ !uunet!coplex!dannie | +-------------------------------------------------------------------------+
rhaar@albert.cs.gmr.com (Robert L. Haar CS50) (02/16/91)
In article <1991Feb15.183139.1285@coplex.uucp>, dannie@coplex.uucp (Dannie Gregoire) writes: |> .... I would assume by the name |> of this group that there are at least a few hardware hacks out there. |> If so, PLEASE answer me this..... |> I don't think of myself as a hardware hacker in the IBM-PC world but I have some information. |> What are the hardware differences between 760K and 1.44M 3.5" |> floppy drives??? The limited information that I have tells me that there |> is no difference, but some experimentation tells me otherwise. |> There are differences, but you might not see them. Both 720K and 1.44M 3.5 diskettes use a very similar layout - same number of tracks,etc. The difference is in the density that data is stored on the disk. This results in the 1.44M drives having data transfer signal rates twice that of the 720K drives. That is why you cannot put a 1.44M drive on a 720K controller and expect it to work. Bob Haar InterNet : rhaar@albert.cs.gmr.com Computer Science Dept., G.M. Research Laboratories DISCLAIMER: Unless indicated otherwise, everything in this note is personal opinion, not an official statement of General Motors Corp.
lairdt@mist.CS.ORST.EDU (Tom Laird) (02/16/91)
Don't let it get to you... I've posted several questions about burning your own bios, and have yet to receive a reply. Other hardware questions have also gone unanswered - guess they're too hard for those reading the news.
pschwart@vms.macc.wisc.edu (Paul Schwartz) (02/16/91)
In article <1991Feb15.183139.1285@coplex.uucp>, dannie@coplex.uucp (Dannie Gregoire) writes... > > I have tried several times to get some answers to some hardware >questions but have recieved NO replies. I would assume by the name >of this group that there are at least a few hardware hacks out there. >If so, PLEASE answer me this..... > > What are the hardware differences between 760K and 1.44M 3.5" >floppy drives??? The limited information that I have tells me that there >is no difference, but some experimentation tells me otherwise. > >If you know the answer to this, PLEASE respond. Thank You. All right already, you've gotten my attention... 2 differences 1) the 1.44 drives have a sensor in them to detect if there is a little hole opposite the write-protect tab. High density disks having the little hole punched. 2) the read/write head on 1.44 drives can punch through a little bit more current, allowing it to affect the 700 ostreds of magnetic coercivity needed to read and write high density disks. (720k disks are at 600 ostreds) F.Y.I. 5 1/2 inch HD drives have a smaller head than the 360k drives and more current, but no little hole. - Z - +-----------------------------------------------------------------------------+ | PauL M SchwartZ | | | PSCHWART@macc.wisc.edu | The cream may rise to the top, | | PSCHWART@wiscmacc.BitNet | but the scum settles from above. | | (608)255-5702 | | +-----------------------------------------------------------------------------+
cs161fhn@sdcc10.ucsd.edu (Dennis Lou) (02/16/91)
In article <1991Feb15.211611.17034@lynx.CS.ORST.EDU> lairdt@mist.CS.ORST.EDU (Tom Laird) writes: >Don't let it get to you... I've posted several questions about burning >your own bios, and have yet to receive a reply. Other hardware questions >have also gone unanswered - guess they're too hard for those reading the news. I often think "This is an easy question, the guy probably already has a dozen answers." Other times, I just scan this newsgroup so quick I don't see them. (this group gets so bloomin' much traffic :-) E-mail me your question and I'll see if I can answer it. -- Dennis Lou || "But Yossarian, what if everyone thought that way?" dlou@ucsd.edu || "Then I'd be crazy to think any other way!" [backbone]!ucsd!dlou |+==================================================== dlou@ucsd.BITNET |Steve Jobs and Steve Wozniak went to my high school.
wkb@cbnews.att.com (Wm. Keith Brummett) (02/16/91)
In article <45196@rphroy.UUCP>, rhaar@albert.cs.gmr.com (Robert L. Haar CS50) writes: > ... Both 720K and 1.44M 3.5 diskettes use a very similar layout ... > The difference is ... > ... That is why you cannot put a 1.44M drive on a 720K controller > and expect it to work. Well, not quite. I have a 1.44M drive on my XT 720K controller, and it works fine. But only at 720K -- definitely not at 1.44M. -- Keith -- | W. Keith Brummett (614) 860-3187 AT&T, Room 3B-202 | | att!cblph!wkb or, 6200 East Broad St. | | w.k.brummett@cblph.ATT.COM Columbus, OH 43213-1550 | `----------------------------------------------------------------------'