UUCJEFF@ECNCDC.BITNET (07/26/89)
ONE THING THERE SEEMED TO BE NO MENTION OF, WHILE TOS 1.4 FORMATS DISKS 100% COMPATIBLE WITH MS DOS, DOES IT ALSO FLAG BAD SECTORS SO YOU CAN USE A DISK WITH BAD SECTORS (AS IN MS-DOS)? I KNOW THERE ARE DISK UTILITIES ON THE ST TO DO THIS, BUT IT WOULD BE NICE IF TOS WOULD DO THIS ALL THE TIME, I.E. IN FORMAT, FILE COPY, AND DISK WRITES. JEFF BEER, CHICAGO IL
apratt@atari.UUCP (Allan Pratt) (07/26/89)
UUCJEFF@ECNCDC.BITNET writes: >One thing there seemed to be no mention of, while TOS 1.4 formats disks >100% compatible with MS DOS, does it also flag bad sectors so you can use >a disk with bad sectors (as in MS-DOS)? >i.e. in format, file copy, and disk writes. TOS has always marked bad sectors when formatting, in exactly the same way that MS-DOS does. No other operation marks bad sectors, under either TOS or MS-DOS, except perhaps a utliity which does that explicitly. This is a good time for the reminder that TOS 1.4's desktop format operation is MS-DOS compatible, but other programs which format disks are not necessarily compatible. ============================================ Opinions expressed above do not necessarily -- Allan Pratt, Atari Corp. reflect those of Atari Corp. or anyone else. ...ames!atari!apratt
hafer (Udo Hafermann) (07/30/89)
apratt@atari.UUCP (Allan Pratt) writes: >TOS has always marked bad sectors when formatting, in exactly the same >way that MS-DOS does. ... What? TOS puts an End-of-chain marker in the appropriate FAT entries, whereas MSDos uses special defective-cluster markers. (Or has that changed in version 1.4?)
ignac@electro.UUCP (Ignac Kolenko) (07/31/89)
In article <1625@atari.UUCP> apratt@atari.UUCP (Allan Pratt) writes: >TOS has always marked bad sectors when formatting, in exactly the same >way that MS-DOS does. No other operation marks bad sectors, under >either TOS or MS-DOS, except perhaps a utliity which does that >explicitly. > >This is a good time for the reminder that TOS 1.4's desktop format >operation is MS-DOS compatible, but other programs which format disks >are not necessarily compatible. > hmmm, thats real interesting allan. my st will format a disk with known bad sectors, and after the format is complete, it will report 728000 (or whatever) bytes free. no mention of bad sectors. just a nice rosy report that the disk is perfect. if it has always marked bad sectors, why does the desktop stop and say that the disk is unusable sometimes, and other times it finished a format, whereas MSDOS will finish a format as normal, and report that xxxx sectors may be bad. in this respect, TOS and MSDOS are much different. also, if bad sectors are marked, why does the desktop insist on copying data on these "marked bad sectors"???? ie: you can do a copy from the desktop, and every once in a while the desktop will pop up a dialog box saying "Data may be damaged". if bad sectors were marked in the MSDOS way, the operating system would know not to write data to that sector in the first place!!! will the truth ever be known??? -- =====Ignac A. Kolenko (The Ig) watmath!watcgl!electro!ignac===== co-author of QuickST, and the entire line of Quick Shareware!!!! "I don't care if I don't win, 'cause I don't care if I fail" from 'Youth Of Today' by SUBURBAN DISTORTION
neil@cs.hw.ac.uk (Neil Forsyth) (07/31/89)
In article <1625@atari.UUCP> apratt@atari.UUCP (Allan Pratt) writes: >TOS has always marked bad sectors when formatting, in exactly the same >way that MS-DOS does. No other operation marks bad sectors, under >either TOS or MS-DOS, except perhaps a utliity which does that >explicitly. I always used to wish that the desktop formatter would allow you to format a bad disk completely (and markbad) so that a severely damaged disk could still be used. Obviously I'd only want this in an emergency and I wouldn't try formatting a disk that looked like a roller coaster. I actually boot up the HD with a damaged disk which I use for nothing else. >============================================ >Opinions expressed above do not necessarily -- Allan Pratt, Atari Corp. >reflect those of Atari Corp. or anyone else. ...ames!atari!apratt +-----------------------------------------------------------------------------+ ! DISCLAIMER: Unless otherwise stated, the above comments are entirely my own ! ! ! ! Neil Forsyth JANET: neil@uk.ac.hw.cs ! ! Dept. of Computer Science ARPA: neil@cs.hw.ac.uk ! ! Heriot-Watt University UUCP: ..!ukc!cs.hw.ac.uk!neil ! ! Edinburgh, Scotland, UK "spam spaM spAM sPAM SPAM, lovely SPAM" ! +-----------------------------------------------------------------------------+
apratt@atari.UUCP (Allan Pratt) (08/01/89)
ignac@electro.UUCP (Ignac Kolenko) writes: >if it has always marked bad sectors, why does the desktop stop and say that >the disk is unusable sometimes, and other times it finished a format ... If there are too many bad sectors, or if Track 0 of the disk is bad, you get the "unusable" message. I forget how many is "too many." As for writing to these bad sectors, it shouldn't happen. If it does, perhaps the sectors in question are marginal: they formatted ok but subsequent accesses were bad. It's also possible that I'm totally wrong and old TOS didn't mark bad sectors correctly. What version are you using? (Original) TOS 1.0 or (Mega) TOS 1.2? After a format of a disk with "known bad sectors" try looking at the FAT. Are there any entries (after the first two) which are not $000? $FF7 is the bad-sector mark, I think. The alert after the format should show the size of the disk after accounting for bad sectors and the two unused clusters at the end of the disk. (Don't open that can of worms, please!) ============================================ Opinions expressed above do not necessarily -- Allan Pratt, Atari Corp. reflect those of Atari Corp. or anyone else. ...ames!atari!apratt
stefan@yendor.phx.mcd.mot.com (Stefan Loesch) (08/01/89)
In article <1629@atari.UUCP> apratt@atari.UUCP (Allan Pratt) writes: >for writing to these bad sectors, it shouldn't happen. If it does, ^^^^^^^^^ But it does >perhaps the sectors in question are marginal: they formatted ok but >subsequent accesses were bad. No. See below. > >It's also possible that I'm totally wrong and old TOS didn't mark bad I think you are :-) >sectors correctly. What version are you using? (Original) TOS 1.0 or >(Mega) TOS 1.2? > I have a 1040 for 3 years now and I noticed that strange behaviour long ago. If you format a disk with bad sectors (DS) the format prg. reports 7XXXXX bytes free (less than the usual 726XXX !), so I assume it found the bad sectors and marked them. If you now write to that disk, everything seems to be OK, only if you try reading it again you get the infamous "check your cable" message. My conclusion: format sees and marks bad sectors, write doesn't care about the mark. By the way, I have 2-26-86 TOS. regards Stefan Loesch uunet!asuvax!mcdphx!yendor!stefan
uace0@uhnix2.uh.edu (Michael B. Vederman) (08/02/89)
Just thought I'd throw my two cents in... DC Formatter version 3.01 and greater does mark bad sectors (and tells you how many) if you enable the verify option. Two cents... - mike -- ------------------------------------------------------------------------------ Double Click Me | Double Click Software | P.O. Box 741206 | Houston, Tx, 77274 ------------------------------------------------------------------------------ See y'all at the Dallas World of Atari Show, Aug. 19-20. Stop by BOOTH 101