gcw20877@uxa.cso.uiuc.edu (George Wang) (11/28/89)
I recently brought a Toshiba 3.5" 1.44 meg High Denisty drive in hope of being able to do a "trick" that is done on Toshiba laptops and IBM PS/2 computers... I wanted to do some high volume backups by using regular, low cost 720K generic disks and formatting them to 1.44 megs.. I heard that Toshiba drives are capable of doing this... I also have a Western Digital WD1006-RA2 controller which supports such "intelligent" drives.. I am also using Pheonix AT BIOS 3.10 However, I have not been able to format the disks at 1.44 megs.. It keeps on giving me invalid media/bad track 0... The funny thing is, is that I can use a legit 1.44 meg diskette, cover the high density hole and format the it at 1.44 megs even though technically the drive thinks it's a 720K disk... But this is ONLY if I use a REAL high density disk and not a fake 720K disk... My question is how can I get it to work.. Is it something with DOS or the BIOS..... I know Toshiba laptops and PS/2 can do this but I can't get mine to work.. (I am running PCDOS 3.2 by the way....) Any ideas? Please email as I don't keep up with the newsgroups... Thanks in advance, George -- George Wang University of Illinois gcw20877@uxa.cso.uiuc.edu
dillon@uhccux.uhcc.hawaii.edu (Ian Dillon) (11/28/89)
In article <1989Nov27.212809.7241@ux1.cso.uiuc.edu> gcw20877@uxa.cso.uiuc.edu (George Wang) writes: > >I wanted to do some high volume backups by using regular, >low cost 720K generic disks and formatting them to 1.44 megs.. In a related topic, are there any programs out there which will allow one to read a 720K disk which has been formatted to 1.44 Megs. using a non- PS2/Toshiba computer? Thanks in advance! Ian * All I really need to know | Ian Dillon * * I learned in kindergarden | * * | BITNET: dillon@uhccux.bitnet * * > R. Fulgham < | I-NET: dillon@uhccux.UHCC.HAWAII.EDU *
usenet@cps3xx.UUCP (Usenet file owner) (11/29/89)
In article <1989Nov27.212809.7241@ux1.cso.uiuc.edu> gcw20877@uxa.cso.uiuc.edu (George Wang) writes: >I wanted to do some high volume backups by using regular, >low cost 720K generic disks and formatting them to 1.44 megs.. >However, I have not been able to format the disks at 1.44 megs.. >It keeps on giving me invalid media/bad track 0... The funny >George Wang >University of Illinois >gcw20877@uxa.cso.uiuc.edu I suggest that you don't try to use 720k disks in a 1.44M format. The media is probably not good enough. The media for a 1.44M disk must be better quality than the media for a 720k disk. I suspect that the people who make these disks test them, and sort them into 3 bins: HD, DD, and rejects. I discourage use of 720k disks at 1.44M, even if they seem to work ok. Your data is probably has value to you! Don't take unnecessary risks. In the rare case that original ideas Kenneth J. Hendrickson N8DGN are found here, I am responsible. Owen W328, E. Lansing, MI 48825 Internet: kjh@pollux.usc.edu UUCP: ...!uunet!pollux!kjh
usenet@cps3xx.UUCP (Usenet file owner) (11/29/89)
In article <5560@uhccux.uhcc.hawaii.edu> dillon@uhccux.UUCP (Ian Dillon) writes: >In a related topic, are there any programs out there which will allow one >to read a 720K disk which has been formatted to 1.44 Megs. using a non- >PS2/Toshiba computer? If a soft-sectored disk has been formatted to 1.44M, then it is a 1.44M disk. It can only be used in the future in a 1.44M drive. I strongly discourage this for 720k media, for the reasons in my last post. In the rare case that original ideas Kenneth J. Hendrickson N8DGN are found here, I am responsible. Owen W328, E. Lansing, MI 48825 Internet: kjh@pollux.usc.edu UUCP: ...!uunet!pollux!kjh
gs940971@longs.LANCE.ColoState.Edu (glen sunada f84) (11/29/89)
In article <5557@cps3xx.UUCP>, usenet@cps3xx.UUCP (Usenet file owner) writes: > In article <5560@uhccux.uhcc.hawaii.edu> dillon@uhccux.UUCP (Ian Dillon) writes: > >In a related topic, are there any programs out there which will allow one > >to read a 720K disk which has been formatted to 1.44 Megs. using a non- > >PS2/Toshiba computer? > > If a soft-sectored disk has been formatted to 1.44M, then it is a 1.44M > disk. It can only be used in the future in a 1.44M drive. I strongly > discourage this for 720k media, for the reasons in my last post. > > In the rare case that original ideas Kenneth J. Hendrickson N8DGN > are found here, I am responsible. Owen W328, E. Lansing, MI 48825 > Internet: kjh@pollux.usc.edu UUCP: ...!uunet!pollux!kjh This is especially true since the true 1.44 Meg formatted diskettes are now less than twice the price of the 720K formatted diskettes in bulk quatities. (i.e. you get what you pay for) The source I have found for thiis is: First Souce Express. I'm sorry that I do not have there address of phone number but they advertise regularly in the back of PC-WEEK. Glen U. Sunada E-MAIL to gs940971@longs.LANCE.ColoState.EDU in ARPA Internet (preferred) ...!ncar!boulder!ccncsu!longs.LANCE.ColoState.EDU!gs940971 (UUCP) We have only ignorence to fear.......
yap@me.utoronto.ca (Davin Yap) (11/29/89)
>mbt@bridge2.ESD.3Com.COM (Brad Turner) writes: >Why are you willing to spend the time to do a floppy disk backup >but aren't concerned about the media you backup on? Why bother >with the backup at all if you are knowingly going to use media >that is suspect to failure? I use Fastback Plus (2.08) to back-up my hard disk, using 720K disks as 1.44 Meg disks. I use both the compression and error-correction options. With compression, I get roughly 1.8 meg of data onto each disk. It is claimed that with the error-correction enabled, up to 8% (?) of the disk can be complete garbage, but your data is still recoverable. The only time I've seen the error-correction portion of Fastback "show its stuff" was recovering from disks that were not already formatted before Fastback got its hands on them. The error-correction works. However, I now pre-format the disks and have not encountered any problems since. Incidently, I regularly use 720K disks as 1.44 Meg disks in everyday use. In the past nine months, I've only encounted one problem disk out of some fifty odd. To me, the only truly important data is that which I create myself; this I place on disks formatted to their correct density. Perhaps I'm a 'slug', but that amounts to less than 720K, including my Masters thesis and a couple papers. FYI, the difference between 1.44 and 720K disks is much less than that between 1.2 and 360K disks. The coercivity of the media is as follows: Disk Type Coercivity (oersteds (sp?)) 360K 300 720K 600 1.2 Meg 600 1.44 Meg 700 These are averages, whether you can use a 720K disk in the HD format depends on the brand and perhaps even the batch. Personally, I use an 'el cheapo' no-name brand, $15/box of ten, and as I've stated before, only one out of fifty of these didn't work (couldn't write to one of the last few sectors on the disk, but most of it was fine). Regards, Davin _______________leave_nothing_to_the_imagination_of_those_without_______________ GOAL: To dance the light fan- |Davin Yap, Mechanical Engineering, U of Toronto tastic in the face of derision,| yap@me.toronto.edu yap@me.utoronto.bitnet from those bland at heart. | ...{pyramid,uunet}!utai!utme!yap
mbt@bridge2.ESD.3Com.COM (Brad Turner) (11/29/89)
gcw20877@uxa.cso.uiuc.edu (George Wang) writes: >I wanted to do some high volume backups by using regular, >low cost 720K generic disks and formatting them to 1.44 megs.. Why are you willing to spend the time to do a floppy disk backup but aren't concerned about the media you backup on? Why bother with the backup at all if you are knowingly going to use media that is suspect to failure? Wouldn't it be more more prudent to spend the additional $$ and have an archive that is not as likely to fail? It is your data to do with as you please, but wouldn't be more sensible to make your archives with the appropriate media? -brad- -- v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v Brad Turner |2081 Shoreline Blvd.|(415) 969-2099 ext 217 | I speak for myself 3Com Corp. |Mtn. View, CA 94043 |mbt@bridge2.ESD.3Com.Com| NOT for my employer
batman@watsci.uwaterloo.ca (Marcell Stoer) (11/30/89)
I've failed to see any satisfactory explanation of what the difference is between a 720K and a 1.44M 3.5" floppy (besides labelling). If you look at a 1.44M floppy, you'll notice there is an extra notch across from the write protect notch that the 720K floppy doesn't have. Most 1.44M drives look for this notch to determine if you have a 1.44 or 720K floppy. Some don't. You can cut the equivalent hole into the 720K disk, but you'd risk contaminating the disk media. There are some companies that sell a converting tool, that does exactly this. I don't recommend it, however, there is no physical difference between a DD and a so to speak HD floppy (besides the notch). The price you pay for your diskettes usually reflects their quality. Marcell Stoer CMBLC :wq
usenet@cps3xx.UUCP (Usenet file owner) (11/30/89)
In article <89Nov28.223437est.19733@me.utoronto.ca> yap@me.utoronto.ca (Davin Yap) writes: >FYI, the difference between 1.44 and 720K disks is much less than that >between 1.2 and 360K disks. The coercivity of the media is as follows: >Disk Type Coercivity (oersteds (sp?)) >360K 300 >720K 600 >1.2 Meg 600 >1.44 Meg 700 I am not familiar with the units of oersteds, or the idea of coercivity. I do know, however, that a very important parameter is #bits/area. Consider: we are all familiar with the increase in quality of audio or video tape when the tape travels at a faster speed. The reason for this is that a larger AREA is used to store the information. Higher signal/noise ratios, and wider frequency response are achieved using this technique. Now, lets compare areas. The area of a 5+1/4" disk has an area of 21.65 sq. in., with a center of radius 1.1" that is not available for use. The area of this center section is 3.80 sq. in. Thus the total area of a 5+1/4" disk which is available for use is 17.85 sq. in. The area of a 3.5" disk is 9.62 sq. in., with a center of radius 0.8" that is not available for use. The area of this center section is 2.01 sq. in. Thus the total area of a 3.5" disk which is available for use is 7.61 sq. in. Some thoughts: Size Area(sq.in.) Bytes/sq.in. $/byte (mail order) ---- ------------ ------------ ------------------- 360k 17.85 20.2 * 10^3 .694 * 10^-6 (@$.25) 1.2M 17.85 67.2 * 10^3 .417 * 10^-6 (@$.50) 720k 7.61 94.6 * 10^3 1.04 * 10^-6 (@$.75) 1.44M 7.61 189.2 * 10^3 1.28 * 10^-6 (@$1.85) The 360k media is the most mature technology. The 1.2M media is the most affordable. The 1.44M media is the most expensive. The minimum quality of a 1.2M disk should be 3.33x better than the minimum quality of a 360k disk, since there is 3.33x the data stored on the same area. The minimum quality of a 1.2M disk only needs to be 0.71x as good as the minimum quality of a 720k disk, since there is 1.67x the data stored on 2.34x the area. The minimum quality of a 1.44M disk should be 9.38x as good as the minimum quality of a 360k disk, since there is 4x the data stored on 0.43x the area. The minimum quality of a 1.44M disk should be 2x better than the minimum quality of a 720k disk, since there is 2x the data stored on the same area. The minimum quality of a 1.44M disk should be 2.79x better than the minimum quality of a 1.2M disk, since there is 1.2x the data stored on 0.43x the area. You can figure out the rest. I think at this point I might be rambling. In the rare case that original ideas Kenneth J. Hendrickson N8DGN are found here, I am responsible. Owen W328, E. Lansing, MI 48825 Internet: kjh@pollux.usc.edu UUCP: ...!uunet!pollux!kjh
userDAR@mts.ucs.UAlberta.CA (David Ross) (12/01/89)
In article <5556@cps3xx.UUCP>, usenet@cps3xx.UUCP (Usenet file owner) writes: >In article <1989Nov27.212809.7241@ux1.cso.uiuc.edu> gcw20877@uxa.cso.uiuc.edu (George Wang) writes: >>I wanted to do some high volume backups by using regular, >>low cost 720K generic disks and formatting them to 1.44 megs.. >>However, I have not been able to format the disks at 1.44 megs.. >>It keeps on giving me invalid media/bad track 0... The funny >>George Wang >>University of Illinois >>gcw20877@uxa.cso.uiuc.edu > >I suggest that you don't try to use 720k disks in a 1.44M format. The ... >DD, and rejects. I discourage use of 720k disks at 1.44M, even if they >seem to work ok. Your data is probably has value to you! Don't take >unnecessary risks. > YES! I agree completely with Ken above. DO NOT use 720K disks formatted at 1.44M!!!! I can almost guarantee that you will have Data errors popping up all over the place. I work in an area that offers a laser- printing service and we very often get people coming in with DD disks formatted at 1.44M and we find our machines can't read their files. We can't help them. Don't risk your information for the sake of a few bucks. ---- David A. Ross, Programmer/Analyst | Internet: david_ross@mts.ucs.UAlberta.CA University Computing Systems | Bitnet: userdar@ualtamts.BITNET 352 Gen Serv Bldg, Univ of Alberta | Uucp: ..!alberta!uqv-mts!david_ross Edmonton, Alberta, Can. T6G 2H1 | Phone: 1-403-492-2462
gcw20877@uxa.cso.uiuc.edu (George Wang) (12/01/89)
In article <1989Nov27.212809.7241@ux1.cso.uiuc.edu> gcw20877@uxa.cso.uiuc.edu (George Wang) writes: >I recently brought a Toshiba 3.5" 1.44 meg High Denisty >drive in hope of being able to do a "trick" that is done >on Toshiba laptops and IBM PS/2 computers... > >I wanted to do some high volume backups by using regular, >low cost 720K generic disks and formatting them to 1.44 megs.. >I heard that Toshiba drives are capable of doing this... Hi all! Just wanted to thanks everyone for the prompt replys... A call to Toshiba Technical Support after Thanksgiving weekend revealed that all that needed to be done was to change a jumper on the drive itself... By default it comes at MEDIA SELECT LOGIC and it needed to be changed to HOST SELECT LOGIC... Now I can format the 720K disks to 1.44 megs like a charm! No need to punch holes or solder!! True, it is a bit risky but for my application of temporary second backups (I mean backups to backups!!) it's fine... Thanks again for the quick replys! George -- George Wang University of Illinois gcw20877@uxa.cso.uiuc.edu
tmurphy@wpi.wpi.edu (Tom [Chris] Murphy) (12/05/89)
In article <236@watserv1.waterloo.edu> batman@watsci.UUCP (Marcell Stoer) writes: >companies that sell a converting tool, that does exactly this. I don't >recommend it, however, there is no physical difference between a DD and a so >to speak HD floppy (besides the notch). The price you pay for your diskettes >usually reflects their quality. While not sure what the difference means, I have seen a visual difference in the material used to make DD and HD disks. The HD disks are noticably more translucent, which would indicate to me a difference in either coating or substrate. ------------------------------------------------------------------------------- Thomas C. Murphy Worcester Polytechnic Institute CAD Lab Internet: tmurphy@wpi.wpi.edu tmurphy@zaphod.wpi.edu BITNET: TMURPHY@WPI BIX: tmurphy CompuServe: 73766,130 If the Universe is constantly expanding, why can't I ever find a parking space?
gt3070b@prism.gatech.EDU (Jeff Watkins) (12/07/89)
Well, about this 720k vs 1.44Meg thing...
With the following equipment & materials I modified my 1.44Meg 3.5" drive
to ignore the presence or absence of a small hole on the left side of a disk:
1 small standard screwdriver.
4" of telephone wire (from an old modular cable)
1 mini toggle switch (available at good old radio shack)
less than 1" of solder
1 soldering iron.
1 knife.
First, I removed the spring driven physical sensor with the small standard
screwdriver. I then soldered two short wires from the terminals of the toggle
switch to the two terminals of the sensor. With the knife, I drilled a small
hole, large enough for the toggle and thread, in a 3.5" drive cover just below
the actual drive.
The only draw back in this approach is that you must physically switch
between 720k and 1.44Meg sizes. With an extra switch, it is probably possible
to set it up so that there is a auto-sense mode and a manual-set mode.
Mind you, I don't suggest trying this at home... but well, everything is up
to you, your conscience, and your pocketbook. There is a slim chance that
you may turn your drive into a permanent 1.44Meg drive, if you can't solder
well.
As to media performance... I purchase 100 generic 3.5" 720k disks, and have
had problems formatting about 4 of them, these I throw out because they
more than likely wont format as 720k either. I haven't had a 1.44Meg formatted
in my "1.44Meg" drive ever fail.
Any way, enough useless talk....
Jeff
--
Jeff Watkins
Georgia Tech (Internet: gt3070b@prism.gatech.edu)
Access Radio (Office: (407)334-5000 Fax: (407)334-3445)brs@unix.cis.pitt.edu (Stupar R Brian) (12/12/89)
In article <4180@hydra.gatech.EDU> gt3070b@prism.gatech.EDU (Jeff Watkins) writes: > >Well, about this 720k vs 1.44Meg thing... > With the following equipment & materials I modified my 1.44Meg 3.5" drive >to ignore the presence or absence of a small hole on the left side of a disk: Another solution to your problem is to find a copy of PcTools' disk formatter (pcformat.exe). Pcformat.exe will format a disk to whatever parameters are given, regardless of whether the disk has one or two holes. This is the procedure that I use, and I have never had any problems with it. My 720K disks format to 1.44Meg every time, without sacrificing reliability. This may be a solution worth considering before you decide to rewire your drive. ------------------------------------------------------------------------------ Brian Stupar "When things are at their darkest, BRS@PITTVMS it's a brave man who can brs@unix.cis.pitt.edu kick back and party." ------------------------------------------------------------------------------
leonard@bucket.UUCP (Leonard Erickson) (12/18/89)
brs@unix.cis.pitt.edu (Stupar R Brian) writes: <In article <4180@hydra.gatech.EDU> gt3070b@prism.gatech.EDU (Jeff Watkins) writes: <> <>Well, about this 720k vs 1.44Meg thing... <> With the following equipment & materials I modified my 1.44Meg 3.5" drive <>to ignore the presence or absence of a small hole on the left side of a disk: <Another solution to your problem is to find a copy of PcTools' <disk formatter (pcformat.exe). Pcformat.exe will format a disk <to whatever parameters are given, regardless of whether the disk <has one or two holes. This is the procedure that I use, and I <have never had any problems with it. My 720K disks format to <1.44Meg every time, without sacrificing reliability. This <may be a solution worth considering before you decide to <rewire your drive. Sorry, but the inability to format 1.44meg disks (under DOS 3.3 or later) is *totally* hardware controlled. If the jumper on the drive is set to check for the second hole, then you will get a hardware error report from the drive if you try to use a 720k disk as a 1.44M. But it shouldn't require re-wiring. On Toshiba drives I *know* that it is controlled by a jumper on the drive (3 positions: software select, hardware select, *reverse* hardware select[!!]). I don't have docs for the Teac drive I'm about to install, but I'll be experimenting with jumper settings... if that fails, I'll get a copy of the docs. -- Leonard Erickson ...!tektronix!reed!percival!bucket!leonard CIS: [70465,203] "I'm all in favor of keeping dangerous weapons out of the hands of fools. Let's start with typewriters." -- Solomon Short