[comp.binaries.ibm.pc.d] super high density formatters

ftw33616@uxa.cso.uiuc.edu (Frank T. Wang) (11/16/90)

has anyoe used those programs that can format a 1.44 meg disk to, say, 1.7 meg?
 and other such HIGH formats?  how unreliable are these?  i figured it'd be
as dangerous as formatting a DD disk HD.

					Frank

gordon@osiris.cso.uiuc.edu (John Gordon) (11/16/90)

	I don't think that the disk actually gets formatted to higher density,
rather an extra track gets formatted that is usually wasted.  I use an extra-
track formatter for my Atari ST and it has never given me any problems, and a
friend uses a similar program for his IBM-clone, but his is kind of a hassle
because you have to run a program to "tell" the BIOS to access the extra
track.  Aside from that, it works OK, I guess.

mig@cunixd.cc.columbia.edu (Meir I Green) (11/17/90)

I would like to try these super high density formatters.
I know that most of the HD disks are *really* rated for *2* megabytes!
It seems to be the drive that isn't capable of the format?
Can someone send me the whereabouts of these files so I can try them?

 * * * * * * *  ======================= Meir Green                           |
* * * * * * * * ======================= mig@cunixd.cc.columbia.edu           |
 * * * * * * *  ======================= N2JPG                                |

w8sdz@vela.acs.oakland.edu (Keith Petersen) (11/17/90)

mig@cunixd.cc.columbia.edu (Meir I Green) writes:
>I would like to try these super high density formatters.
>Can someone send me the whereabouts of these files so I can try them?

WSMR-SIMTEL20.ARMY.MIL [26.2.0.74]

Directory PD1:<MSDOS.DSKUTL>
 Filename   Type Length   Date    Description
==============================================
FDFORM16.ZIP  B   76080  901031  Format floppies for greater density/storage

This file is also available from Detroit Download Central.

Keith
--
Keith Petersen
Co-SysOp, Detroit Download Central 313-885-3956 (212/V22bis/HST/V32/V42bis)
Internet: w8sdz@vela.acs.oakland.edu,  w8sdz@eddie.mit.edu,  w8sdz@brl.mil
Uucp: uunet!umich!vela!w8sdz                         BITNET: w8sdz@OAKLAND

gordon@osiris.cso.uiuc.edu (John Gordon) (11/18/90)

mig@cunixd.cc.columbia.edu (Meir I Green) writes:

>I would like to try these super high density formatters.
>I know that most of the HD disks are *really* rated for *2* megabytes!
>It seems to be the drive that isn't capable of the format?
>Can someone send me the whereabouts of these files so I can try them?

	If you look closer (at least on some of the disks) it says "2.0
Megabytes *UNFORMATTED* Capacity".  Now, I may be stupid, but what the heck
good is it to be this way, you can't use it until it's been formatted!!
I've always wondered about this....

rb9a@watt.acc.Virginia.EDU (Raul Baragiola) (11/18/90)

In article <1990Nov18.020651.13744@ux1.cso.uiuc.edu> gordon@osiris.cso.uiuc.edu (John Gordon) writes:
>mig@cunixd.cc.columbia.edu (Meir I Green) writes:
>
>>I would like to try these super high density formatters.
>>I know that most of the HD disks are *really* rated for *2* megabytes!
>>It seems to be the drive that isn't capable of the format?
>>Can someone send me the whereabouts of these files so I can try them?
>
>	If you look closer (at least on some of the disks) it says "2.0
>Megabytes *UNFORMATTED* Capacity".  Now, I may be stupid, but what the heck
>good is it to be this way, you can't use it until it's been formatted!!
>I've always wondered about this....

To reasons for this. 1) the formatted capacity depends on the type of format.
2) the marketing guys will always give you the maximum possible number in
the specs.

Raul A. Baragiola                               \Internet: raul@virginia.edu
Dept. Nuclear Engnr. and Engnr. Physics          \Phone: (804)-982-2907
University of Virginia, Charlottesville, VA 22901 \ Fax: (804)-924-6270

jaapv@accucx.cc.ruu.nl (Jaap Verhage) (11/19/90)

In article <1990Nov16.035524.22022@ux1.cso.uiuc.edu> ftw33616@uxa.cso.uiuc.edu (Frank T. Wang) writes:
>
>has anyoe used those programs that can format a 1.44 meg disk to, say, 1.7 meg?
> and other such HIGH formats?  how unreliable are these?  i figured it'd be
>as dangerous as formatting a DD disk HD.
>
>					Frank
I've been using FDFORMAT 1.5 for quite some time now, and have had
no reliability problems. I'm formatting DSDD disks on a HD drive, 5
1/4", to 820 KB, same on 3 1/2". HD disks get formatted to 1.44 MB
and 1.72 MB, respectively. 


-- 
Regards, Jaap.

Jaap Verhage, Academic Computer Centre, State University at Utrecht, Holland.
jaapv@cc.ruu.nl      +<-*|*->+      I claim *every*thing and speak for myself

kdq@demott.COM (Kevin D. Quitt) (11/19/90)

In article <1990Nov18.020651.13744@ux1.cso.uiuc.edu> gordon@osiris.cso.uiuc.edu (John Gordon) writes:
>	If you look closer (at least on some of the disks) it says "2.0
>Megabytes *UNFORMATTED* Capacity".  Now, I may be stupid, but what the heck
>good is it to be this way, you can't use it until it's been formatted!!
>I've always wondered about this....


    Well, since there are "tricky" ways of putting more data on the disk
than "standard", what number should they list? 1.44MB because that's
standard, or 1.8MB because that's what you can get if you're lucky? The
point is that by saying 2MB unformatted, you can compare it to other
media of a similar type. 

-- 
 _
Kevin D. Quitt         demott!kdq   kdq@demott.com
DeMott Electronics Co. 14707 Keswick St.   Van Nuys, CA 91405-1266
VOICE (818) 988-4975   FAX (818) 997-1190  MODEM (818) 997-4496 PEP last

                96.37% of all statistics are made up.

walk@mrcnext.cso.uiuc.edu (Todd Walk) (11/21/90)

ftw33616@uxa.cso.uiuc.edu (Frank T. Wang) writes:


>has anyoe used those programs that can format a 1.44 meg disk to, say, 1.7 meg?
> and other such HIGH formats?  how unreliable are these?  i figured it'd be
>as dangerous as formatting a DD disk HD.

>					Frank


All programs for the IBM that do this add 1 extra sector per track (or 2 or 3..)At 1 extra sector per track, a 720K IBM disk (9 sec., 80 tracks) is increased
to 800K (about the most 1MB unformated disks can hold while formated).
With a 1.44MB disk you can squeeze on 2 or 3 extra sectors per track, giving	between 1.6-1.8MB.  As for the reliability of adding these extra sectors to the
tracks, that depends on the individual diskettes.  A value called the          
coercitivity determines the magnetic strength of the disk and is very important
in determining how much information can be put on it.  For 1MB 3.5" disks it
is about 600, 2MB 3.5" about 700.  The amount of coercitivity that a disk
actually has is a factor of the manufacturing process and can vary              significantly.  If it is lower than it is supose to be, the disk will be    
unreliable with the extra sectors.  Plus, old disks tend to lose their
coercitivity.

As for why you can't get 1MB of storage on a 1MB unformated disk       
(and 2MB on a 2MB...), disk manufacturers measure the amount of bytes that
can be reliably placed on the disk (of course you can get more bytes on the 
outside tracks than on the inside tracks).  Therefore, with a constant speed
disk drive (such as the ones on IBMs), you get much less than the unformated
density.

						Todd Walk
						walk@mrcnext.cso.uiuc.edu