iiitsh@cybaswan.UUCP (Steve Hosgood) (11/10/89)
A while back there was a discussion along the lines of "why can some people write 360K disks in 1.2M drives when others can't?". Even the physics of the situation was a problem - how *can* an AT 80-track drive write the wider tracks of a 40 track disk? People suggested that the drives may have split heads to allow this, but this seems to be wrong. NEC for instance claim they don't use split-head drives. I discovered that I could write 360K reliably on *one* of our ATs at work but not on another. Both had NEC drives, an FD1155C which wrote the 360K disks OK, and an FD1157C which didn't. So I swapped the drives from one machine to the other. The effect stayed with the *machines*! Now the 1157C wrote 360K disks and the 1155C didn't. So I swapped the controllers. Still the effect stayed with the machines! I started to suspect the BIOS. The machine that could write 360K disks had a CAC-AMI (?) BIOS, the other had an AWARD 3.01. I discovered another machine in our office had an AWARD 3.03, so I swapped BIOS ROMs over. The fault vanished! I then discovered that the machine with the AWARD 3.03 had been able to write 360K disk all along, using a TEAC FD556FR drive, so it definately seems that with the right BIOS, just about any drive can write 360K. So scrap your AWARD 3.01 and get something better! Is 3.03 the latest, or has anyone seen a 3.04? There is still a bug in AWARD 3.03, in that the soft reset doesn't work properly. If you use RAMDRIVE it gets left in limbo by the CTL-ALT-DEL sequence, and doesn't come back up. Hard reset works OK (on RAMDRIVE 1.19 anyway). Does anyone know a fix for this problem please?. Steve iiitsh@pyr.swan.ac.uk PS: I have not found out how to write 720K 5.25" disks in an AT drive yet. I believe it may not be possible. The media description byte on 720K disks is $FB, which is the same as 1.2M disks. I suspect this confusion means that an AT will use the wrong write current to try and write to a 720K disk. Any comments anyone? Is the guy who wrote FDFORMAT listening?
jca@pnet01.cts.com (John C. Archambeau) (11/12/89)
iiitsh@cybaswan.UUCP (Steve Hosgood) writes: >I discovered that I could write 360K reliably on *one* of our ATs at work but >not on another. Both had NEC drives, an FD1155C which wrote the 360K disks OK, >and an FD1157C which didn't. So I swapped the drives from one machine to the >other. The effect stayed with the *machines*! Now the 1157C wrote 360K disks >and the 1155C didn't. So I swapped the controllers. Still the effect stayed >with the machines! > >I started to suspect the BIOS. The machine that could write 360K disks had a >CAC-AMI (?) BIOS, the other had an AWARD 3.01. I discovered another machine >in our office had an AWARD 3.03, so I swapped BIOS ROMs over. > >The fault vanished! I then discovered that the machine with the AWARD 3.03 >had been able to write 360K disk all along, using a TEAC FD556FR drive, >so it definately seems that with the right BIOS, just about any drive can >write 360K. > >So scrap your AWARD 3.01 and get something better! Is 3.03 the latest, or >has anyone seen a 3.04? There is still a bug in AWARD 3.03, in that >the soft reset doesn't work properly. If you use RAMDRIVE it gets left in >limbo by the CTL-ALT-DEL sequence, and doesn't come back up. Hard reset >works OK (on RAMDRIVE 1.19 anyway). My 16 MHz AT has been able to read/write to 360K disks with 1.2 Mb drives all along. If you have Phoenix BIOS 286 Plus 3.10 you don't have to worry, it knows what 360K format is. I never did like the Award BIOS, now I have a justification as to why. /*--------------------------------------------------------------------------* * Flames: /dev/null (on my Minix partition) *--------------------------------------------------------------------------* * ARPA : crash!pnet01!jca@nosc.mil * INET : jca@pnet01.cts.com * UUCP : {nosc ucsd hplabs!hd-sdd}!crash!pnet01!jca *--------------------------------------------------------------------------* * Apple Computer, Inc. is really the Anti-Christ! *--------------------------------------------------------------------------* * Note : My opinions are that...mine. My boss doesn't pay me enough to * speak in the best interests of the company (yet). *--------------------------------------------------------------------------*/
cs4g6ag@maccs.dcss.mcmaster.ca (Stephen M. Dunn) (11/13/89)
In article <859@cybaswan.UUCP> iiitsh@cybaswan.UUCP (Steve Hosgood) writes:
$I started to suspect the BIOS. The machine that could write 360K disks had a
$CAC-AMI (?) BIOS, the other had an AWARD 3.01. I discovered another machine
$in our office had an AWARD 3.03, so I swapped BIOS ROMs over.
Hmm ... my brother has an AWARD BIOS in his AT, which he's had for over
two years now, and can write 360K disks with no problems ... I don't know
what version his BIOS is, but it obviously isn't too recent.
--
Stephen M. Dunn cs4g6ag@maccs.dcss.mcmaster.ca
<std_disclaimer.h> = "\nI'm only an undergraduate!!!\n";
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They say the best in life is free // but if you don't pay then you don't eatwnbell@sybil.cs.Buffalo.EDU (William Bell) (11/14/89)
Hi! What do you think of AMI 386-BIOS?? What version is latest??? Any known bugs in older versions? Please e-mail me.. Out Of Touch BBS - 716-825-4268 from 8pm-8am! FIDO 1:260/170... Online games!
akcs.larry@nstar.UUCP (Larry Snyder) (11/15/89)
>What do you think of AMI 386-BIOS?? What version is latest??? >Any known bugs in older versions? My AMI 386 bios is dated March of 89 - and there is an update available which I should have installed this weekend.
dgaulden@dcscg1.UUCP (David E. Gaulden) (11/15/89)
In article <255E2685.14123@maccs.dcss.mcmaster.ca> cs4g6ag@maccs.dcss.mcmaster.ca (Stephen M. Dunn) writes: >In article <859@cybaswan.UUCP> iiitsh@cybaswan.UUCP (Steve Hosgood) writes: >$I started to suspect the BIOS. The machine that could write 360K disks had a >$CAC-AMI (?) BIOS, the other had an AWARD 3.01. I discovered another machine >$in our office had an AWARD 3.03, so I swapped BIOS ROMs over. > > Hmm ... my brother has an AWARD BIOS in his AT, which he's had for over >two years now, and can write 360K disks with no problems ... I don't know >what version his BIOS is, but it obviously isn't too recent. I run an Everex System 1800 286/10 which orig came with AMI BIOS. I later changed it to Award 3.01 and updated to Award 3.03. I have never had any problems writing 360k via the 1.2m drive. However, the AMI BIOS did present problems with environment space, hence the switch to Award. -- ------------------------------------------------------------------------------ IRL:Dave Gaulden | "Man who says, 'It cannot be done', DCSC Columbus, Ohio | Should not interrupt man who is dgaulden@dcsc.dla.mil | doing it."
csirmaz@porthos.rutgers.edu (Laszlo Csirmaz) (11/16/89)
Maybe all of this staff I want to explain is known for everybody in the netland, so I apologize advance.... The difference between the 360k and 1.2M floppy drive is twofold. First, the 1.2M drive has twice as many track as the 360k drive does (80 tracks versus 40). Second, each track on an 1.2M floppy contains more sectors than on the 360k floppy (15 versus 9). Thus writing a 360k floppy on a 1.2M drive, the drive has to do the following: use low density and use every other track only. The first of them is built in property of the drive: either it can do it or it can't. The second is a property of the software (presumably the BIOS) so it can automatically double the track number. The BIOS decides what kind of floppy it is dealing with in the following way. If the floppy is changed then it reads in the first sector on track 0 -- first with high density, and if unsuccesfull then with low density. In the first case the floppy is regarded as a 1.2M, in the second as a 360k. Each subsequent transaction to the drive is done according to this original decision, until the floppy is not changed. A nice exception is the "format" routine. It may, or may not inform the BIOS about the newly formatted floppy. Thus after formatting a floppy with the /4 parameter (if that works) it may be useful to take the floppy out and insert again, asking for a "dir". But anyway, the BIOS has the right to do what it wants, this is only ONE of the possibilities. If it does differently, then..... The head of a 1.2M floppy drive is about half as narrow as that of a 360k driver. This means that the 1.2M driver can modify smaller region thus the floppy produced in this way may be unreadable by a traditional 360k driver! And vice versa. If a floppy was written by a 360k drive, then a 1.2M drive cannot overwrite every information on it. The gaps might be filled with strong magnetic flips, which may cause erroneous reading. This is the reason why certain "format" programs do not allow reformat to 1.2M a floppy which has been formatted (maybe mistakenly) to 360k. Hope this helps ... Laci
cs4g6ag@maccs.dcss.mcmaster.ca (Stephen M. Dunn) (11/19/89)
In article <621@dcscg1.UUCP> dgaulden@dcscg1.dcsc.dla.mil.UUCP (David E. Gaulden) writes:
$I run an Everex System 1800 286/10 which orig came with AMI BIOS. I later
$changed it to Award 3.01 and updated to Award 3.03. I have never had any
$problems writing 360k via the 1.2m drive. However, the AMI BIOS did
$present problems with environment space, hence the switch to Award.
That's rather an odd result. The BIOS has nothing whatsoever to
do with the environment ... in fact, the BIOS doesn't even have anything
to do with memory at all.
What kind of problems did you have?
--
Stephen M. Dunn cs4g6ag@maccs.dcss.mcmaster.ca
<std_disclaimer.h> = "\nI'm only an undergraduate!!!\n";
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They say the best in life is free // but if you don't pay then you don't eat