stevens@prlhp1.prl.philips.co.uk (Francis Stevens) (08/02/89)
With all the PD disk formatters available which enable you to format a floppy in a non-standard way (i.e. 10 sectors per track, 84 tracks per side) which gives more than 720K per drive, does anyone have any advice or warnings about doing this ? An extra 80K or so per disk seems a good idea but they must have settled on 720K for a reason (?). Any comments ? Francis Stevens stevens@prl.philips.co.uk
lodzins@pilot.njin.net (Dean Lodzinski) (08/03/89)
I have an external double sided Atari drive (I think it is a 314) which can handle disks formatted to 82-83 tracks. The drive in my 1040 doesn't like these disks and causes a lot of read/write errors. If you go over the standard format, you may run into reliability problems. I try to keep to the standard format disks. I may get an extrak 100K with some other formats, but if I lose the data it isn't worth it. -- Dean Lodzinski CSRA19@TURBO.Kean.edu or lodzins@pilot.njin.net 47 Mercury Circle Dean Lodzinski on FoReM FNET at node 133 South Amboy, NJ 08879 D.Lodzinski on GEnie. 73727,1641 on CompuServe USA (In order of importance)
huuhilo@kannel.lut.fi (Arto Huuhilo) (08/03/89)
stevens@prlhp1.prl.philips.co.uk (Francis Stevens) writes: >With all the PD disk formatters available which enable you to format >a floppy in a non-standard way (i.e. 10 sectors per track, 84 tracks per >side) which gives more than 720K per drive, does anyone have any advice >or warnings about doing this ? An extra 80K or so per disk seems a good idea >but they must have settled on 720K for a reason (?). Any comments ? Most disk manufacturers test their disk according to the IBM standard (i.e 80 tracks/720 kbytes). So the tracks 81-84 may not be reliable. Anyhow, I have used those formatter programs and problems have occurred only with cheap nameless disks. There have been no problems with Basf, Sony and TDK disks to name but a few. -- Arto Huuhilo Internet : huuhilo@kannel.lut.fi huuhilo@kuula.lut.fi
bgr@wild.Rice.EDU (Robert G. Rhode) (08/05/89)
720k is a standard (IBM-compat.) disk format, so I assume Atari was simply conforming to the industry standard. For example, I was unable to get a PS/2 to format a disk to 820k, but I format them to 720k all the time - for media transfer purposes. The PS/2 won't read disks formatted by my Atari, but my Atari will read disks formatted by the PS/2. Robert Rhode | "Today's champion rhode@ricevm1.rice.edu | is tomorrow's crocodile shit." bgr@uncle-bens.rice.edu | Monty Python : Contractual Obligation Album
rosenkra@hall.cray.com (Bill Rosenkranz) (08/05/89)
In article <955@prlhp1.prl.philips.co.uk> stevens@prlhp1.prl.philips.co.uk (Francis Stevens) writes:
=With all the PD disk formatters available which enable you to format
=a floppy in a non-standard way (i.e. 10 sectors per track, 84 tracks per
=side) which gives more than 720K per drive, does anyone have any advice
=or warnings about doing this ? An extra 80K or so per disk seems a good idea
=but they must have settled on 720K for a reason (?). Any comments ?
=
=Francis Stevens
=stevens@prl.philips.co.uk
i know i'll get razzed on this but...
as far as i know, not all floppy drives are created equal. i have been
lead to believe that hnot all can access beyond track 80. if you use
your ST alot, odds are you will have to replace the floppy eventually
(i am on my 3rd in 3 years on my 1040, my mega4 is about due as well...),
especially w/o a hard disk. this means you could get a drive which may
not be able to get at track 80+. you can also get blank disks (in the
states) for < $0.80 so why bother?
correct me if i am wrong about all disks/controllers accessing tracks
above 80... (anecdotal: i have a brand new ds/dd floppy i got from
atari directly which won't go in either 1040 or mega4 since it has the
connections "reversed" and the power cable/ribbon cable are not long
enough to "flip"...how's THAT for compatibility!).
-bill
rosenkra@boston.cray.comf-leoe@IFI.UIO.NO (Lars-Erik 0sterud) (08/05/89)
TOS 1.4 formated disk will work all right on IBM... I small change in the format or boot-sector i think.... Anyway. AVant-Garde's PC_DDRVR.SYS makes it possible for an IBM to read old Atari disks too (some CLONES even read then now - NOT original IBM's :-) Lars-Erik 0sterud / Summer & Christmas: / leoe@ifi.uio.no / f-leoe@ifi.uio.no / ____________________/ _______________________/
harry@moncam.co.uk (Jangling Neck Nipper) (08/06/89)
In article <CMM.0.88.618299761.f-leoe@kyrre.uio.no> f-leoe@IFI.UIO.NO (Lars-Erik 0sterud) writes:
TOS 1.4 formated disk will work all right on IBM...
I small change in the format or boot-sector i think....
I've no idea about 1.4, but I've noticed that the version of TOS I'm
running creates FAT tables with a media descriptor of 0xF7, and uses a
512 byte cluster size, 5 block FAT tables, root 11..17, data 18..1439
(for double sided). Now PC's won't recognise this, but if you format
a 3.5" disk on a PC, you get descriptor 0xF9, and the ST *will* access
these correctly. So the answer for anyone wishing to maintain
compatability in TOS < 1.4 would be to create the file systems on the
PC. Of course it's a simple matter to write a program to create an
0xF9 file system anyway.saj@chinet.chi.il.us (Stephen Jacobs) (08/07/89)
In article <426@brazos.Rice.edu>, bgr@wild.Rice.EDU (Robert G. Rhode) writes: > transfer purposes. The PS/2 won't read disks formatted by my Atari, but my > Atari will read disks formatted by the PS/2. This phenomenon annoys enough people that it's worth while repeating: nearly any disk formatted on an ST will be handled properly by a PS/2 if the first 3 bytes of the 'boot sector' are made (3 bytes in hex to follow) EB 34 90. I've done this for years with no problems. The reverse process, formatting on the PS/2 and using on both machines, suffers from the famous problem that IBM machines don't put unique serial numbers on each disk. Yeah, CHKDSK recognizes that there's something funny about the disk, and some compatibles won't take them, but for ST - PS/2 exchange, this is enough. Steve J.
alderaan@tubopal.UUCP (Thomas Cervera) (08/08/89)
(This same article could be posted before. If so, sorry. We have had problems on this system here, so that I'm not sure.) In article <426@brazos.Rice.edu> rhode@ricevm1.rice.edu writes: >720k is a standard (IBM-compat.) disk format, so I assume Atari was simply conforming to the industry standard. For example, I was unable to get a PS/2 >to format a disk to 820k, but I format them to 720k all the time - for media >transfer purposes. The PS/2 won't read disks formatted by my Atari, but my >Atari will read disks formatted by the PS/2. But this has nothing to do with the format of your disks but only with that ATARI's GEM Desktop does not format the disks in 'real' MS-DOS/PS-2 compatible format (the boot sector has not the 100% data format expected by MS-DOS). In TOS 1.4, as I know, this problem is solved. Finally. Media portability should not be a problem while using so-called 'fat' disks, if your formatting program will set up consistant data structures representing this disk (boot/configuration sector, SAT, root directory etc.) Other OS's should be able to handle this if they are following their own guidelines. Definetely, a disk format bigger than 720k is not a non-standard disk format at all. The only problem you could have with this is a decrease of reliability and/or I/O performance. But this depends on 1) what media you're using (in my experience, noname disks always are not that reliable) 2) what disk drive you're using (maybe your disk drive spin frequency is too high so that you can't write 11 sectors per track because then the 1st sector would be over- written by the 11th. Of course, this problem would also appear while writing to a 11sec disk coming from another machine bacause, while writing, TOS's interest only focusses on what the configuration information of that disk is. This could damage data. Besides, I would not recommend formatting disks with more than 83 tracks on origional ATARI disk drives (SF354/SF314) because this could cause the R/W heads to bounce against the slide boundaries. If this happens frequently, this could dis-align or -even worse- severely damage your drive.). Concluding, if you have important data to store on your disks, I would re- commend to use data compression instead of fat disks. -- Thomas Cervera | UUCP: alderaan@tubopal.UUCP SysMan RKOpdp (RSTS/E) | alderaan%tubopal.UUCP@TUB.BITNET (saves $$$) D-1000 Berlin 30 | ...!pyramid!unido!tub!opal!alderaan Motzstrasze 14 | BITNET: alderaan%tub@DB0TUI11.BITNET