I need some help......

[TanZyr]

Kronos:

Sorry, matey. Amiga floppy drives spin at half the speed of PC floppies, ergo one of the reasons PC drives have such a hard time reading Amiga floppies. Ask Jens, he's the expert with floppies.

re: variable speed floppies - mostly this occurred on the Mac, and Amiga OS 1.x, esp commercial games, from what I recall. Might be mis-remembering, though...

[Kronos]

Nope .....

Amiga-DD-floppies spin just like PC-ones (Ior how do you think my experment with the
Atari-floppy worked). Amiga-HD-floppies do spin at half the speed of PC-ones as
Paula isn't capable of doing the double amount of data it would get otherwise.

But this reduced speed is used throughout the whole disk, while the old
800k Mac-floppies used different speed for differnet cylinders. Mac-HD-floppies are
again HW-compatible to those used in PCs.

The floppy-controller in a PC has a fixed lenght for the sync-gap in it's HW (3bytes AFAIR),
while the Amiga uses only 2.

[Piru]

re: variable speed floppies - mostly this occurred on the Mac, and Amiga OS 1.x, esp commercial games, from what I recall. Might be mis-remembering, though...

You mis-remember.

You can't change the rotation speed of the amiga floppy drive via software. It's either not rotating or rotating.

The only way to get something in between would be to quickly turn the motor on/off, but this would result in "jumpy ride" and inconsistent result between various floppy drives (or fail to work at all, depending on the hardware). It'd also be very deadly for the floppy drive and the disk.

The "slow speed" was used when manufacturing (==writing) these protected disks using some advanced mass duplication system called "Trace Machine". The slow speed allowed to write a long track that is imposible to write on real amiga. So, since the real amiga can't lower the speed the disk can't be copied.

For details, see CAPS FAQ.

So, only old Macs (and perhaps some other exotic hw?) used variable speed floppy drive.

[mikeymike]

Ok guys, take a step back from this argument and try to make it a constructive one.  Don't tell the other person that he's talking rubbish and is the truth, it REALLY DOESN'T HELP.

Quote sources of information, they must be out there somewhere.  And not just sources of information that other users have said, something that looks remotely official would be useful.

[Piru]

Low level format:

Hard Disk Formatting and Capacity

In particular:

Low-level formatting is the process of outlining the positions of the tracks and sectors on the hard disk, and writing the control structures that define where the tracks and sectors are. This is often called a "true" formatting operation, because it really creates the physical format that defines where the data is stored on the disk. The first time that a low-level format ("LLF") is performed on a hard disk, the disk's platters start out empty. That's the last time the platters will be empty for the life of the drive. If an LLF is done on a disk with data on it already, the data is permanently erased (save heroic data recovery measures which are sometimes possible).

If you've explored other areas of this material describing hard disks, you have learned that modern hard disks are much more precisely designed and built, and much more complicated than older disks. Older disks had the same number of sectors per track, and did not use dedicated controllers. It was necessary for the external controller to do the low-level format, and quite easy to describe the geometry of the drive to the controller so it could do the LLF. Newer disks use many complex internal structures, including zoned bit recording to put more sectors on the outer tracks than the inner ones, and embedded servo data to control the head actuator. They also transparently map out bad sectors. Due to this complexity, all modern hard disks are low-level formatted at the factory for the life of the drive. There's no way for the PC to do an LLF on a modern IDE/ATA or SCSI hard disk, and there's no reason to try to do so.

...

STOP! Warning: You should never attempt to do a low-level format on an IDE/ATA or SCSI hard disk. Do not try to use BIOS-based low-level formatting tools on these newer drives. It's unlikely that you will damage anything if you try to do this (since the drive controller is programmed to ignore any such LLF attempts), but at best you will be wasting your time. A modern disk can usually be restored to "like-new" condition by using a zero-fill utility.

From: low level format

The distinction between high-level formatting and low-level formatting is important. It is not necessary to low-level format a disk to erase it: a high-level format will suffice for most purposes; by wiping out the control structures and writing new ones, the old information is lost and the disk appears as new. (Much of the old data is still on the disk, but the access paths to it have been wiped out.)

From: high level format

As I have said (probably too often, sorry) modern drives do not need to be low-level formatted by the end user, and in fact cannot be LLFed outside the factory due to their precision and complexity. However, it seems that the need to LLF hard disks on the part of users has never gone away. Like some primordial instinct, many PC users seem to have a fundamental desire to LLF their modern disks. Maybe it is built into the genetic code in some way yet undiscovered. ;^) In fact, even if it were possible, the vast majority of the time that someone "needs" to LLF a hard disk today, it is not really necessary. Many users jump quickly to wanting to try an "LLF" whenever they have a problem with their hard disk, much the way many jump to re-installing their operating system whenever it gives them trouble.

From: format utilities

In general Hard Disk Geometry and Low-Level Data Structures is a good read. And no, it's not PC only.


RDB structure:

- AmigaOS includes devices/hardblock.h

- Amiga Developer CD 2.1
ADCD_2.1:Reference/DevCon/Washington_1988/Devcon_Extras/HardDisk/HardBlocks
ADCD_2.1:Reference/HTML/Devices_Manual_guide/node0079.html
ADCD_2.1:Reference/HTML/Devices_Manual_guide/node007A.html
ADCD_2.1:Reference/HTML/Devices_Manual_guide/node007B.html
ADCD_2.1:Reference/HTML/Includes_and_Autodocs_2._guide/node0041.html
ADCD_2.1:Reference/HTML/Libraries_Manual_guide/node041F.html
ADCD_2.1:Reference/HTML/Libraries_Manual_guide/node0420.html
ADCD_2.1:Reference/HTML/Libraries_Manual_guide/node0421.html
ADCD_2.1:Reference/HTML/Libraries_Manual_guide/node0422.html
ADCD_2.1:Reference/HTML/Libraries_Manual_guide/node0423.html
ADCD_2.1:Reference/HTML/Libraries_Manual_guide/node0424.html

[Jope]

First of all, your BOOT Hard Drive should ALWAYS be set to ID # 0. Your next SCSI device should be set for ID # 1 and so on. The higher the ID number the lower the priority.

You've got it the wrong way around. ID6 has higher prio than ID0

(ever wonder why the controller is usually at ID7?)

Information about scsi.

[carls]

Quote sources of information, they must be out there somewhere. And not just sources of information that other users have said, something that looks remotely official would be useful.

Here is from the Swedish manual for ExpertPrep and FaaastPrep from GVP (translated from swe->eng by me):

"Low level format: By clicking on this button, you send the command for doing a low level format of the current drive. A low level format is something the hard disk manufacturer use to prepare an all-new hard disk to accept system specific structures (such as blocks and tracks). Before you can prepare or format a new hard disk, this must be low level formatted. This is made by the manufacturer and should normally not be done more than once."

So... It's already carried out by the manufacturer and you should not do it again. Then it goes on:

"WARNING! This command destroys all data on your hard disk!"

Then comes a screenshot of a requester, and lastly:

"A low level format will destroy all data on the drive. Exceptions from this are the Quantum 'S' and 'LPS' series. On these disks a low level format has no effect whatsoever."

This is from the book "Faaast Prep 2.0 / Version 2 Svensk", (c) 1992 GVP and Karlberg & Karlberg.

The above information is available on page 36 in the Swedish translation.

[carls]

Oh, and I probably should add that I have never in my whole life low-level-formatted a hard disk. I've taken disks from PCs running both Windows and Linux, put them directly in my A1200, partitioned them and then just quick formatted them. I have never had any trouble whatsoever.

I've also put Amiga formatted disks in PCs and formatted them with fdisk or Windows without any low-level format on the PC.

[Jope]

Oh, and I probably should add that I have never in my whole life low-level-formatted a hard disk. I've taken disks from PCs running both Windows and Linux, put them directly in my A1200, partitioned them and then just quick formatted them. I have never had any trouble whatsoever.

I lowlevelformatted my very first own hard disk when I was still a kid.. (I had done it on PCs with ESDI controllers before, but that's different - you can change some parameters (like the capacity!) on ESDI drives yourself by re-lowlevelformatting them. NOT APPLICABLE TO SCSI/IDE, NO USE LOWLEVELFORMATTING THEM, EVER)

This time it took so very long that I got bored and switched off the machine.. Big mistake! Dead machine, the HD reported write errors every time I tried to do anything to it. I called all around Finland for support for my problem.. In the end I found out that if the drive starts the LLF, it must be completed before you can use it again.

Luckily my drive was one of those that go into a "dumb mode" if the LLF is interrupted.. The only command it accepts is LLF, so I restarted the LLF, did something else while it formatted (took something like four hours :-D) and the drive worked again. Quite a shock for a kid who almost thought he ruined some expensive HW.. I was lucky, many others haven't been. :-(

Please note, that some drives accept the LLF command, but don't actually do anything - they complete immediately. Guess why? - You are correct, it's because you are not supposed to do it yourself and the vendors got tired of replacing drives the users botched up.

Anyway, this is some empiric experience that came from messing with LLF, it's not hearsay or rumour.

Bottom line: DON'T LOWLEVELFORMAT ANY MODERN SCSI or IDE HARD DRIVE. (also don't mix setting up partitions with LLF, it's as far from LLF as Pluto is from the Sun.)











[Edit: I was a little harsh - there are situations when a LLF is good, so it's actually not "never" but "99,999% of the time never" .. I just want to stress the fact that you shouldn't do it, because it is potentially dangerous, 99.999% of the time totally unnecessary and if you have a power outage or your cat presses reset or something, you might end up with an expensive paperweight!]

[maxplunder]

To Everyone:

I'm sorry that I started theis post for help.  I have and will always do a Low-Level Format on drives when I recieve them.  I have never "KILLED" a HD in my life.  I've been working with IDE, SCSI, and Firewire drives.  My computer experence is such that I have rescued dead drives "BY" a LLF.  Since 1984, I have worked on computers.  I build them.  And though Amiga is fairly new to my experence, the SCSI bus is still the same.

 I just wish that if ya'll want to argue about this please move it to a new thread and don't make the person asking for help sort through all this garbage.

If I ever need any help again and post it here I hope I never have to read through all of this BULL again

Thank you
Doug

[iamaboringperson]

If I ever need any help again and post it here I hope I never have to read through all of this BULL again

Good one DoomMaster. :-x
Where do you get the name? You tell people how best to destroy their HDD's? Perhaps next time you will tell us how to stick screw drivers in power sockets? You are the master of doom. :-x

[Framiga]

by iamaboringperson on 2003/8/31 23:35:26


Quote:


If I ever need any help again and post it here I hope I never have to read through all of this BULL again


Good one DoomMaster.
Where do you get the name? You tell people how best to destroy their HDD's? Perhaps next time you will tell us how to stick screw drivers in power sockets? You are the master of doom.

he, he, he . . .effectively, was the first think i've thought too. (the style is the same . .but)

But i'm not 100% sure. Are there someone that is be able to trace this "new" guy? :-D

Ciao

[maxplunder]

This is for EVERYBODY:

I don't really care about the arguement.  I guess I'll just have to find somewhere else to ask questions about the amiga.  all i'm getting now is flames.

  BTW the "new" guy (ME) is the one who posted this question in the first place.  I will report this thread to the moderators.  All I did was ask an Honest Question and wanted an Honest Answer.  This forum remindes me of the Democratic Underground Forum.  The first few posts I recieved was helpful, but it soon turned to a flame fest, vulgarity and all.

I hope you are all satisified u have lost a member

Maxplunder aka Doug Merritt
Origional Thread Poster

[Kronos]

I think "new guy" was targeted at Doommaster who has been nothing
but trouble sofar.

[Framiga]

by Kronos on 2003/8/31 23:58:00

I think "ne guy" was targeted at Doommaster who has been nothing
but trouble sofar.

Sorry . .what "ne guy" stay for? can you explain me better?

Ciao

[Kronos]

me was just missing a "w" here  :-D  ;-)  :-o