Multibooter Posted August 29, 2009 Author Posted August 29, 2009 (edited) Among the archived floppies, which I am re-formatting, I have come across a 5.25" floppy disk, marked as follows:"BASF1/9696 tpi certifiedone sided/double densitysectors softFlexyDisk 5.25""Many CP/M computers and some early IBM PC like computers used 80 track (96 TPI) 5.25 inch drives with double density format. This was sometimes called "quad density", as it was twice the data capacity of "double density" 40-track (48 TPI) drives. These drives, 40 or 80 track, rotated disks at 300 RPM. Later on, the PC compatibles went to "high density" 1.2M 5.25" drives and diskettes, with drives which were able to run at 360 RPM." http://retrotechnology.net/herbs_stuff/drive.html"If you do have any quad density disks, you can use them as good quality double density disks." http://www.britishtelephones.com/floppy1.htm"Format b: /1 /4 /u" formats the floppy Ok to 180K, but that's very little for a 96tpi floppy disk"Format b: /F:1.2 /u" formats the floppy Ok to 1.2MB, but with FMT v2.6 of the Disk Copy Plus utilites I got a bad sector (" 1 tries failed" [DOS format tries 3 times, therefore no bad sectors; FMT v2.6 marks the sector bad after only 1 try fails]). The 2nd side of the floppy is a little weak.With which DOS format parameters should this floppy be formatted on a 5.25" max.1.2MB floppy drive? Are there any special uses for this rare type of floppy disk? Edited August 29, 2009 by Multibooter
dencorso Posted August 29, 2009 Posted August 29, 2009 Try with Chris Hochstätter's freeware FDFORMAT, from true DOS. If the media is OK, I'm positive it'll be able to format it to 1.2 MB and even to 1.44 MB. I've done it on the first attempt with some MD2-HD 5.25" Maxcell flopies I still have, by using FDFormat.
Multibooter Posted August 30, 2009 Author Posted August 30, 2009 (edited) I've done it on the first attempt with some MD2-HD 5.25" Maxcell flopies I still have, by using FDFormat.Hi dencorso,Your MD2-HD 5.25" floppies are double-sided, but the floppy here is a single-sided one, I can't remember having seen one before.Thanks for mentioning FDFormat, but if I remember right, it requires the TSR FDRead to stay resident so that non-standard floppy formats can be read.I have kind of given up to format this floppy to more than 360kB, I'll just keep it as a curiosity."Format b: /T:80 /N:15 /U" (it does the same as "Format b: /F:1.2") formatted it Ok to 1.2MB, but subject to the weakness identified by FMT 2.6. Apparently the "/1" parameter [=format one side only] doesn't work with 5.25" floppies, only with 3.5" floppies.I have tried to test-format this 5.25" SS floppy with 22Disk to CP/M DEC Rainbow format (SS:DD:96tpi:5.25inch), but my max.1.2MB 5.25" floppy disk drive couldn't do it, just error messages.BTW, when I formatted a 3.5" floppy disk in a Win98 Dos window to this specific CP/M format, everything was Ok. No problem writing under Win98 files from the HDD to this CP/M floppy disk in the floppy drive of my Inspiron laptop, and then reading the CP/M floppy on another Win98 computer. Data files, however, get changed a little in the process of transferring from DOS format -> CP/M format -> DOS format: a whole bunch of Hex 1A characters (up to 40 maybe) gets appended to the end of a file. And then there is a little trick: only use 720kB 3.5" floppy disks for reading and writing in CP/M format under Win98, 1.44MB floppies don't work. Edited August 30, 2009 by Multibooter
dencorso Posted August 30, 2009 Posted August 30, 2009 Thanks for mentioning FDFormat, but if I remember right, it requires the TSR FDRead to stay resident so that non-standard floppy formats can be read.That's what the FDFORMAT.DOC says. But I've found out that it depends on the BIOS and the controller your computer has. With my ASUS K7V600-X, which FDD controler is inbuilt in its 8237A southbridge, I've never needed to use FDREAD.EXE, and have been able to read even the strangest formats directly, both in DOS and in Win 98SE!!! I have formatted MD2-HD 5.25" from 1.44 MB DS to 160 kB SS and have done the same to MF2-HD 3.5" floppies, from 1.78 MB DS to 160 kB SS, and they still work after more than two years! However, to be able to format MF2-HD 3.5" floppies to 760 kB or less, I found out it's necessary to close their high-density hole with any common adhesive sticker. Now, while those floppies can be read and written even by Win 98SE, I only succeeded at formatting them with the help of FDFormat (without FDRead, in my case).
Multibooter Posted August 30, 2009 Author Posted August 30, 2009 (edited) That's what the FDFORMAT.DOC says. But I've found out that it depends on the BIOS and the controller your computer has. Thanks dencorso. With FDFormat I could format on an old Toshiba 3200 portable, under DOS 6.22, this rare SS-HD 5.25" floppy disk to 600kb (half the capacity of DS-HD 5.25" floppies), without using FDRead.I used the following parameters: FDFormat b: t80 h1 s15 c1 d224No problems reading and writing under DOS 6.22 to the floppy disk formatted in this special format with the T3200. I could not test it under Win98, I am away from my dual-core desktop and don't have an external 5.25" floppy disk drive for my Inspiron 7500 laptop.However, to be able to format MF2-HD 3.5" floppies to 760 kB or less, I found out it's necessary to close their high-density hole with any common adhesive sticker.This confirms my experience that I can read, write and format 96tpi CP/M formats onto a taped 1440kB 3.5" floppy, from a DOS window under Win98 using 22Disk, but not onto an untaped 1440kB floppy. The internal floppy drive of my Inspiron 7500 laptop works better with taped 1440kB floppies than with original 720kB floppies when I read/write/format CP/M formatted 3.5" floppy disks under Win98.I have formatted MD2-HD 5.25" from 1.44 MB DS to 160 kB SS and have done the same to MF2-HD 3.5" floppies, from 1.78 MB DS to 160 kB SS, and they still work after more than two years!I just unsuccessfully tried to create a floppy disk image with DCF 5.3 of this specially formatted 600kB floppy. At track 66 I got an error message "Address mark not found". FDFormat did something during the formatting which DCF didn't like.I then checked this 600kB SS floppy with Anadisk, which produced the following messages:" This diskette has a DOS format [i.e. not CP/M, for example] but is not a standard type."" This is a single-sided DOS format, but both sides have data. Do you want to check both sides?" This means that formatting a floppy as single-side format with FDFormat will not delete the data on the unused side - a potential security risk. Then Anadisk displays "Track 66: Sector 5, ID but no data found". This message appears when I checked only one side and when I checked both sides. Since both DCF and Anadisk found something strange at track 66 of this floppy formatted with FDFormat, I would be careful. In the best case using a non-standard DOS format means that you cannot create a .dcf floppy image for archiving the floppy. In the worst case it may signal a potential data loss problem. Maybe you should consider moving the stuff from non-standard formatted floppies to floppies with a standard DOS format. Edited August 30, 2009 by Multibooter
dencorso Posted August 30, 2009 Posted August 30, 2009 I have images of them all, by now! Most were created with WinImage v. 8.10.8100 (or the previous version of it). Some, like the formats used by DOS 1.x, WinImage cannot handle, because it needs a BPB (which hadn't been invented yet, in DOS 1.x times!) to find out what the floppy format is. For those I used the excellent freeware DiskImage, by Mike Brutman (the whole of his PC Jr site is worthy of a visit too...). In all cases, I've favoured raw images (.IMA files), which I can browse with WinHex and boot from with grub4dos if I'm in the mood. After I learned how to boot from raw images, I have had little use for my oddly formatted diskettes, but I decided to keep them, just to see how long they would hold their strange formats. I have one MD2HD (5.25") formatted to 160 kB and 20+ MF2HD (3.5") formatted strangely, and they are now 2 years old or more and counting, and remain perfect. Isn't that great? I had always read everywhere that high-density floppies formatted to low density formats wouldn't hold the format for long... Now, these floppies were, all of them, new media, never used before. With used media I've had mixed results: they do not necessarily format perfectly, and bad sectors are a common finding.Later edit: for what it's worth, here's also a working direct download link to the trusty old Rundegren's Freeware Floppy Image 1.5.2.0 for Win (which, however, only supports 3.5" floppies).
Multibooter Posted August 31, 2009 Author Posted August 31, 2009 (edited) Problem converting boot sectors to a different floppy formatI have come across a little monster among the floppies to be archived:It is a 5.25" 360kB bootable floppy which boots into IBM DOS 2.00 (German) of 9-Aug-1983. I can create a 5.25" floppy image from it Ok, the 5.25" floppy re-created from the image file boots fine into IBM DOS 2.00 (German).But I cannot convert this 5.25" 360kB floppy image correctly to 3.5" 720kB format, so that I can boot into IBM DOS 2.00 (German) on my Inspiron 7500 laptop, which has only a 3.5" floppy drive (laptops don't come with 5.25" floppy drives). I have tried both WinImage under Win98 and the "Convert" selection of Disk Copy Plus under DOS 6.22. The converted 3.5" 720kB floppy does NOT boot anymore. When booting from the "converted" 3.5" floppy, I get the error message:" Falscher/fehl.Befehlsinterpreter" = "wrong/missing command interpreter".During the conversion of the floppy format, DCP displays that the orignal 5.25" 360kB floppy had 12 sectors used by the system, while the resulting 3.5" 720kB floppy has 14 sectors used by the system. WinImage does not display any conversion information.When I compared with Anadisk the original 5.25" floppy and the "converted" 3.5" floppy, there were 2 changes:- the media byte changed from "fd" to "f9"- the original 5.25" floppy had 2 sectors/FAT, while the "converted" 3.5" floppy had 3 sectors/FAT, which may explain why command.com could not be found.This little monster shows that one cannot trust the converted image files of bootable floppies created by WinImage or DCP. After conversion one should always test: does the converted floppy really boot?Both WinImage and DCF can write Ok without format conversion the 5.25" floppy onto a 3.5" floppy, but the trouble is that this non-standard floppy (i.e. a 3.5" floppy pretending to be a 5.25" floppy) boots fine on a Toshiba T3200 (80286), but when trying to boot from it on an Inspiron 7500 (Pentium 3), the system hangs during the boot process.Is there a tool which can properly convert the boot sector from a 5.25" floppy to a standard 3.5" floppy?P.S.:Same problem when booting with a 3.5" 720kB "IBM PC-DOS v2.10 (German)" floppy converted from 5.25" 360kB format (err msg: Fehler:DSKT,Platte/Kein System)Same problem when booting with a 3.5" 720kB "IBM PC-DOS v2.10 (US)" floppy converted from a 5.25" 180kB format (err msg: Non-System disk or disk error) Edited August 31, 2009 by Multibooter
dencorso Posted August 31, 2009 Posted August 31, 2009 (edited) Support for 1.2 MB MD2HD (5.25") floppies was added with PC-DOS 3.00 and support for 720 kB MF2HD (3.5") floppies arrived only with PC-DOS/MS-DOS 3.20. Older versions will refuse to boot from these formats, no matter what. Thus PC-DOS 2.xx will boot at most from 360 KB floppies (or images), PC-DOS 1.10 and MS-DOS 1.25 will boot at most from 320 KB floppies (or images) and PC-DOS 1.00 will only boot from 160 KB floppies (or images).So I suggest you:1)Use FDFormat to format a common MF2HD (3.5") to 360 kB (with the high-density tab taped)! 2)Use DiskImage or WinImage to collect a raw image from the 5.25" floppy.3)Use WinImage to transfer without formatting the raw image to the 360 kB 3.5" floppy you've just prepared! This works in my machine, so it's worth giving it a shot on yours. Good luck!Now, in case your hardware does not accept the MF2HD (3.5") 360 kB created with FDFormat (which lets you produce a floppy perfectly within the original specs), then the best ideia is to boot MS-DOS 7.10 from a floppy, run Grub4DOS and boot the image of the PC-DOS 2.00 from it. In case you decide to go this way I can provide you a more detailed how to (and so can jaclaz who first interested me on the *fantastic* Grub4DOS ).@jaclaz: DCOPY seems interesting, no doubt, and I shall give it some testing shortly. The programs I'm talking about, however, are those that, at lest for me, are proven to work well with those really old versions of DOS, which are very picky as to formatting detail, although they may be tricked into using 3.5" floppies, as long as the FDD plays along. Edited August 31, 2009 by dencorso Added a lot of info
jaclaz Posted August 31, 2009 Posted August 31, 2009 @dencorsoI'll try again re-submitting (pushing ) DCOPY:http://users.telenet.be/jbosman/applications.htmlDCOPY is a single pass floppy disk copy program. It makes use ofextended memory, hard disk, or conventional memory. It is capable ofmaking more copies of the same disk, without re-reading the disk. Itcan copy a variety of floppy formats, including those formatted withFDFORMAT. It can copy non-DOS disks, sush as Linux disks, thanks toan autodetect function. It's also possible to make/restore diskimages to/from a file. Another possibility is to format a disk, verifyand compare a disk.You must use DCOPY as follows: DCOPY source target [options]source: This can be a drive (A: or B:) or a file (a disk image)target: This can be a drive (A: or B:) or a file (a disk image) - You cannot specify a disk image for both source as target. - You can specify wildcards with source disk image names. - When you create a disk image with .ZIP extension, the disk image is automatically compressed with PKZIP. - When you restore a disk image with .ZIP extension, the disk image is automatically uncompressed with PKUNZIP. The zip file must contain a file with the same name, but with extension .IMGoptions: /s : Use a swap file instead of extended memory. /c : Use conventional memory instead of extended memory or swap file. With this options enabled, the copy process must be done in multiple passes. /v : Verify if data is written correctly. The data is read again and compared with the original data. /f : Always format target disk the same as the source disk. /vo : Verify only a disk, do not copy. A target drive is not necessary. /fo : Format only a disk, do not copy. A target drive is not necessary. /f:x : Use a predefined disk format, this can be 160,180,320,360,720,800,1200,1440,1600,1722 Every format indicates the capacity of the disk in Kbytes. /a : Autodetect the disk format, this is done automatically if the disk is a non-DOS disk. When used with the /fo option, the disk is formatted at the highest possible capacity. (You will need a TSR like FDREAD that enables you to read the disk) /a1 : Autodetect the number of sectors per track at every track. This is usefull for some forms of copy protection, where the disk is formatted with a different number of sectors at some tracks. /a:x : Retry to read/write a track x times in case of a read/write error. /sk : Skip all read/write errors. /t:x : Use x tracks. /n:x : Use x sectors per track. /s:x : Use x sides. /qm : Quiet mode, does not make the silly beeps. /i:x : Use an interleave of x. /ss:c: Use Sector Spinning of x. Changing this number may speed up/slow down the copy process. /hs:x: Use a head settle time of x. If your drive reports read errors, you can try setting this value to at least 25. /fs : Do not use FAT selection. /x:n : Make/Restore n disk images. Dcopy will create or restore n disk images from/to disk. The images have the name you specified as first or second argument with the extension .001 to .n /co : Compare two disks. Reads the first disk and compares it with a second disk. You can also compare disks with a disk image. /fdr : Creates an executable called fdread.exe on the target disk. This program allows you to read the extra high density diskettes. This option is only used with the /fo option. /q : Does a quick format. Writes only the logical information, does not really format the disk. This option is only used with the /fo option.jaclaz
Multibooter Posted September 4, 2009 Author Posted September 4, 2009 (edited) So I suggest you:1)Use FDFormat to format a common MF2HD (3.5") to 360 kB (with the high-density tab taped)! 2)Use DiskImage or WinImage to collect a raw image from the 5.25" floppy.3)Use WinImage to transfer without formatting the raw image to the 360 kB 3.5" floppy you've just prepared! This works in my machine, so it's worth giving it a shot on yours. Good luck!Converting DOS 2 boot floppies from 5.25" -> 3.5" mediaThanks, dencorso, it worked fine on my old Inspiron 7500 laptop. I used DCF instead of DiskImage or WinImage.Under DOS 6.22 I pre-formatted a taped 1.44MB floppy disk with FDFormat: "FDFormat A: /4"Then, in a DOS window under Win98, I extracted with DCF on top of this pre-formatted floppy a .dcf image of the DOS 2.10 boot floppy, with the options: Format=OFF and Fast=ON.I was able to boot from this special 3.5" floppy into DOS 2.10, both with my Inspiron 7500 laptop (2000) and with an older Toshiba T3200 (1987)Under Win98 the files on this specially-formatted 3.5" floppy displayed Ok, but I was not able to read from or to write to it without a blue screen + disk error msg. In any case, it's nice to know that one could boot into DOS 2.1 on a laptop without a 5.25" floppy drive, if ever the need came up. Edited September 16, 2009 by Multibooter
CharlotteTheHarlot Posted September 9, 2009 Posted September 9, 2009 @Multibooter ...FYI, Svend Olaf Mikkelsen also developed a method for live booting from floppy images a few years back. I won't bother explaining it since he has it pretty thoroughly documented on this page The Boot Floppy.It is 9x based (well, FATxx actually).I meant to mention this a while ago, sorry I got busy elsewhere!
jaclaz Posted September 9, 2009 Posted September 9, 2009 FYI, Svend Olaf Mikkelsen also developed a method for live booting from floppy images a few years back. I won't bother explaining it since he has it pretty thoroughly documented on this page The Boot Floppy.Nice. Just for the record, grub4dos or Syslinux/memdisk can map a floppy image to (fd0) (please read as A:\) allright.As long as the OS inside the floppy is a "protected mode" one and there are no programs that use undocumented ways to access the floppy, it will work allright.jaclaz
dencorso Posted September 10, 2009 Posted September 10, 2009 For what's worth, here is my MENU.LST for loading the good old classics with Grub4DOS:default 2 timeout 3 title CP/M-86 1.1 (1983)map --mem /CPM86_11.IMA (fd0)map --hookrootnoverify (fd0)chainloader --force (fd0)+1title PC-DOS 1.00 (1981)#image is 160kB map --mem --heads=1 --sectors-per-track=8 /PCD100.IMA (fd0)map --hookrootnoverify (fd0)chainloader --force (fd0)+1title PC-DOS 1.10 (1982)#image is 320kB map --mem --heads=2 --sectors-per-track=8 /PCD110.IMA (fd0)map --hookrootnoverify (fd0)chainloader --force (fd0)+1This runs OK from a common 1.44 MB bootable MS-DOS 7.10 floppy.Besides the usual DOS files, grub.exe, menu.lst and the raw floppy images, of course, are needed.DRVSPACE.BIN can be removed, and a one line CONFIG.SYS, containing just "INSTALL=GRUB.EXE" should be added.
Multibooter Posted September 10, 2009 Author Posted September 10, 2009 (edited) Data recovery problemOne of my 720kB floppies to be archived has a very nasty CRC error in track 0. WinImage reports "Disk Error on track 0, head 0. Floppy Error". DCF gives the msg "Diskette bad. CRC read error" on Track 0. BadCopy is of no help either ("No file found in rescue Mode #1, you may try Mode #2", and under Mode#2 it recovered garbage into File1.EXE ). Similar story with EaseUS Data Recovery Wizard under WinXP.AnaDisk reports:Track 0, Side 0: Sector 8 data error, Sector 9 ID but no data foundTrack 0, Side 1: Sector 5 data errorall other tracks were OkVga-Copy v5.3 was able to recover correctly, in a Win98 DOS window under SlowDown v1.01, with a regular 3.5" floppy disk drive, about 50% of the files on the floppy, with their correct file names and correct content. I had selected the maximum of 99 retries; Vga-Copy was then reading for about 45 minutes the bad and weak sectors of track 0.LS-120 floppy drives are much better at reading bad floppies than regular floppy drives. Vga-Copy unfortunately does not work with LS-120 floppy drives, it accesses the floppy controller directly.AnaDisk v2.10, DiskDupe v4.07, DCF v5.3, CopyQM v5 and WinDupe v1.02 don't work in a Win98 DOS window with an LS-120 floppy drive either. TeleDisk v2.23 allows to address the floppy controller either directly or via the BIOS, but TeleDisk doesn't work either in a Win98 DOS window.I would like to continue my data recovery with an LS-120 floppy drive because of its superior error correction. Which Win98 recovery software or sector-copier works with an LS-120 floppy drive and is actually able to recover floppies with a bad track 0? Edited September 11, 2009 by Multibooter
dencorso Posted September 11, 2009 Posted September 11, 2009 I would like to continue my data recovery with an LS-120 floppy drive because of its superior error correction. Which Win98 recovery software or sector-copier works with an LS-120 floppy drive and is actually able to recover floppies with a bad track 0?None that I know of. But, by all means, clone the disk with Anadisk to a good floppy, while you still can, before using Anadisk more extensively to try to salvage something from the bad sectors. And do clean the heads of your drive before proceeding, and after you're finished with the bad floppy.
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