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Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: barney on May 22, 2008, 01:54:00 AM

Title: 1.44 MB floppys used in 880K Amiga Disk Drives
Post by: barney on May 22, 2008, 01:54:00 AM
I have always been told that you can not use a 1.44 mb floppy in a standard Amiga drive.  Well, I decided to put this theory to the test. I formatted a regular everyday 1.44 floppy and guess what?  It worked absolutely fine!  I now use these disks all the time to play games, save data, etc.

Whoevey else out there that heard the same, give it a try.  You will never have to worry again about scrambling for DS DD disks anymore.  Good luck

Barney
Title: Re: 1.44 MB floppys used in 880K Amiga Disk Drives
Post by: on May 22, 2008, 02:02:57 AM
hehe. no plastic tape over the hole on the side marked HD or anything? I've been wasting tape! :)
Title: Re: 1.44 MB floppys used in 880K Amiga Disk Drives
Post by: barney on May 22, 2008, 02:05:23 AM
I don't even use tape.  I will keep the tape idea in mind in case I run into any troubles in the future.

Barney
Title: Re: 1.44 MB floppys used in 880K Amiga Disk Drives
Post by: countzero on May 22, 2008, 02:07:36 AM
AFAIK, the problem with the HD disks is the medium is different from DD disks and requires much more power to magnetise. This will eventually put a stress on your amiga floppy drive and one day kill it.
Title: Re: 1.44 MB floppys used in 880K Amiga Disk Drives
Post by: rkauer on May 22, 2008, 02:11:21 AM
 Those HD diskette have a prone to fail due they different magnetic surface.

 In every disk box I buy, I usually only take 5~6 for Amiga stuff. :angry:

 BTW: the original Amiga floppy unit is DD, so putting an HD disk inside doesn't matter. It will only be formatted in 880k.
Title: Re: 1.44 MB floppys used in 880K Amiga Disk Drives
Post by: on May 22, 2008, 02:11:51 AM
countzero - is this true only when writing to the disks, or when reading from them as well?
Title: Re: 1.44 MB floppys used in 880K Amiga Disk Drives
Post by: stefcep2 on May 22, 2008, 02:19:38 AM
i found that over a short time these disks fail even if you tape the hole up.
Title: Re: 1.44 MB floppys used in 880K Amiga Disk Drives
Post by: barney on May 22, 2008, 02:21:00 AM
Countzero, does the Amiga floppy really have the technology of saying "ok.... I am not successfully magnetizing this disk so I better up my power to see if that works".  I could be wrong, but if the drive does not have the necessary power to magnetize the disk in the first place, then the disk simply would not work (unreadable).  Who knows, maybe I am wrong.  Maybe the Amiga floppy can up it's power...who knows.  I have not had any problems yet, but I will keep an eye on it.
Title: tape shmape
Post by: weirdami on May 22, 2008, 02:56:19 AM
The tape thing doesn't do a thing because DD drives don't have a sensor on that side. I remember tape on 5 1/4" floppies making them write-protected, and doing tape on the other side protected the back side of the disk in the same way. One thing you could try is drilling a hole in a DD disk and seeing if it will work in an HD drive. I remember people trying that a long time ago. Dunno what the results were.
Title: Re: 1.44 MB floppys used in 880K Amiga Disk Drives
Post by: Ilwrath on May 22, 2008, 03:32:00 AM
Quote
Countzero, does the Amiga floppy really have the technology of saying "ok.... I am not successfully magnetizing this disk so I better up my power to see if that works".


Nope.... I don't think you'll have that happen either.  But, you'll get a lot more random track and sector errors.  And you'll get a much shorter lifespan for the data.  I used some HD disks on Amiga maybe 10 years ago.  Almost all of those disks were unreadable within a year or two.  Where as the DS/DD disks from 15+ years ago (stored in the same boxes) STILL have 90% or more readable.

Also, you only need the tape on a DS/DD disk to read it on a High Density drive.  (If a high density drive detects the hole in the disk, it will try to read it as high density, and will not retry to read it as a low density after the high density read fails.)
Title: Re: 1.44 MB floppys used in 880K Amiga Disk Drives
Post by: orange on May 22, 2008, 07:06:47 AM
@rkauer, @weirdami

thats not true, at least some DD drives do have HD sensor. I know my A500 original drive has it.

the problem is that such diskettes are not reliable, in a few hours or days they might become unreadable.
Title: Re: 1.44 MB floppys used in 880K Amiga Disk Drives
Post by: rkauer on May 22, 2008, 09:11:42 AM
Quote

orange wrote:
@rkauer, @weirdami

thats not true, at least some DD drives do have HD sensor. I know my A500 original drive has it.

the problem is that such diskettes are not reliable, in a few hours or days they might become unreadable.


 I know they have. But the switch is useless on Amiga units (but the rare HD ones).

 I agree with using HD disks on Amiga is a no-no. Since HD disks needs a stronger magnetic field to properly store data, the DD unit can't cope with it and the disk will lost the magnetic data stored in an unpredictable time. :angry:
Title: Re: 1.44 MB floppys used in 880K Amiga Disk Drives
Post by: weirdami on May 22, 2008, 09:15:23 AM
@orange

That's a useless bit of technology.
Title: Re: 1.44 MB floppys used in 880K Amiga Disk Drives
Post by: Speelgoedmannetje on May 22, 2008, 10:25:49 AM
Haven't had any problems with it so far :-?
(and believe me, I've done it alot)
Title: Re: 1.44 MB floppys used in 880K Amiga Disk Drives
Post by: on May 22, 2008, 06:07:29 PM
I'm still curious about the above statement that the use of HD disks will damage the DD drive in an Amiga. Personally, I do not care if my floppies all die 3 seconds after I take them out of the drive - to me they are only for moving files from my PC to the Amiga, so if they become useless after accomplishing that, it's ok. However, if the heads in my drive are going to be damaged, that's another story. I have never heard of this problem before; has anyone here actually damaged a drive this way?
Title: Re: 1.44 MB floppys used in 880K Amiga Disk Drives
Post by: klx300r on May 22, 2008, 06:20:31 PM
Quote

orange wrote:
@rkauer, @weirdami

thats not true, at least some DD drives do have HD sensor. I know my A500 original drive has it.

the problem is that such diskettes are not reliable, in a few hours or days they might become unreadable.


hmm well Ive been using HD disks with my 1581 dating back 1991 and not even one bad block has been noticed! ironically brand new DD's used on both my miggy and 64/128 systems have failed on me after only a few months of use :-?
Title: Re: 1.44 MB floppys used in 880K Amiga Disk Drives
Post by: Damion on May 22, 2008, 07:57:39 PM
I've used HD floppies with "OK" results, they work but I've found there are more instances of errors, disks that need to be written to twice, etc.

Quote
Where as the DS/DD disks from 15+ years ago (stored in the same boxes) STILL have 90% or more readable.


I fired up a bunch of my old Amiga floppies a few weeks back, and fortunately, most of them seem to be fine as well. (The C64 disks were OK as of about 3 years ago.) I picked up a bunch of (unwanted) floppies recently, they were stored properly but came from a humid environment. Interestingly, about 50% of the ones I tried were junk, couldn't even be formatted without errors.

BTW -- If anyone needs a good source for DD floppies, the Diskette Connection (http://www.disketteconnection.com/store/default.asp) are a great bunch to deal with. (The Imation brand floppies they sell are made in the US, which is kind of cool to see these days.)

Title: Re: 1.44 MB floppys used in 880K Amiga Disk Drives
Post by: amigadave on May 22, 2008, 08:55:28 PM
@-D-,

Diskette Connection is sold out for DD diskettes.
Title: Re: tape shmape
Post by: Fester on May 22, 2008, 09:05:39 PM
Quote

weirdami wrote:
One thing you could try is drilling a hole in a DD disk and seeing if it will work in an HD drive. I remember people trying that a long time ago. Dunno what the results were.


I used to do that in college to save money. I'd stack the DDs on a 2x4 and drill'em. Never had a problem.
Title: Re: tape shmape
Post by: amiga_3k on May 22, 2008, 09:17:34 PM
IIRC the A1200s from ESCOM/AmigaTechnologies actually used modified HD PC-drives as DD Amiga drives. In those machines, taping of the hole was needed to use HD floppies as DD.

I never had any problems with HD floppies used as DD. Must state that I always bought No-brand floppies (cheap dutch guy :-)).

Title: Re: 1.44 MB floppys used in 880K Amiga Disk Drives
Post by: Damion on May 22, 2008, 09:24:22 PM
Quote

amigadave wrote:
@-D-,

Diskette Connection is sold out for DD diskettes.


Ah, bum deal. I ordered a few boxes some months back, "just in case" I'd need a few someday. Maybe they'll get more in.

Title: Re: 1.44 MB floppys used in 880K Amiga Disk Drives
Post by: Zac67 on May 22, 2008, 10:06:08 PM
Since the early 90s DD and HD floppies were made with the exact same media inside.

But: once these get written to with a HD drive (e.g. PC preformatted) they may be troublesome in DD drives. According to several experts, HD heads write 'harder' bits that are just overlayed with the 'softer' DD bits. The DD bits deteriorate faster than the harder HD ones and practically get overwritten from underneath. This effect depends largely on the exact specs of the media used (which we usually know nothing of).

I can't confirm this from my own experience though (been using an Amiga HD drive for the last 15 years), but for valuable data it's definitely worth considering. Actually I don't trust floppies further than I can throw them...
Title: Re: 1.44 MB floppys used in 880K Amiga Disk Drives
Post by: orange on May 23, 2008, 05:54:04 PM
Quote
HD heads write 'harder' bits that are just overlayed with the 'softer' DD bits.


hmm, thats interesting.. so would this help:
-cover the hole and format it on PC as 720Kb,
-reformat on Amiga ?
Title: Re: 1.44 MB floppys used in 880K Amiga Disk Drives
Post by: Tricky on May 23, 2008, 06:03:34 PM
I realised a few years back that most cheap floppy drives on PCs these days don't even have the DD/HD hole detection switch!  They can't read or write DD disks at all because of this.  I had to replace the floppy drive in my PC with an older one in order to transfer things to and from my Amiga.

I've always used Sony HD floppies on my Amiga, and they seem to work fine.  Apparently, there is some overlap in the specification in the range of field strength required for HD/DD, and Sony disks tend to be in the overlap.  I can't remember where I read that now.
Title: Re: 1.44 MB floppys used in 880K Amiga Disk Drives
Post by: on May 23, 2008, 06:32:39 PM
I don't even have a regular pc with a floppy drive at all; some years ago I needed to make a sata driver disk for a win xp install on a friend's machine, so I picked up a teac usb floppy drive for cheap. it's great because I've gone through 4 generations of computers since and I don't have to worry about transplanting a drive or buying new ones. (i've noticed that floppy drives tend to have a greater lifespan if they're not in the system case having dirty air blown at them by the cooling fans.) the drive, btw, definitely has the HD sensor.

I used to find that I could never rely on floppy discs marked with a brand name to have been manufactured in a consistent manner - I would buy them in boxes of 100 and noticed that the batches had remarkably different failure rates, so now I always buy my discs from radio shack because they're cheap and I never saw any correlation between cost and the discs' quality.
Title: Re: 1.44 MB floppys used in 880K Amiga Disk Drives
Post by: Methanoid on June 18, 2012, 09:27:22 AM
Thread resurrection time;

What about the 1.76FDD in the A4000. Is that "safe" to use with 1.44Mb HD floppies but to format them as 880K for games etc?
Title: Re: 1.44 MB floppys used in 880K Amiga Disk Drives
Post by: psxphill on June 18, 2012, 10:28:57 AM
Quote from: Zac67;398134
Since the early 90s DD and HD floppies were made with the exact same media inside.

That is not true.
 
http://www.retrotechnology.com/herbs_stuff/guzis.html
Title: Re: 1.44 MB floppys used in 880K Amiga Disk Drives
Post by: Zac67 on June 18, 2012, 10:52:50 AM
HD drives can handle/overwrite 'harder' bits, so they should be fine with HD floppies whether in HD mode or not. Actually, any DD floppy ever written to in a HD drive and then rewritten in a DD drive can be a problem over time... (I don't know whether HD drives vary the write current according to the currently used density but the write field from a HD head will always be denser.)

I guess the effect largely varies with the different media types. Additionally, many late DD drives are probably using HD heads anyway, so you may or may not notice bit rot over time - but you've been warned. ;)
Title: Re: 1.44 MB floppys used in 880K Amiga Disk Drives
Post by: spaceman88 on June 18, 2012, 01:13:10 PM
Quote from: Methanoid;696774
Thread resurrection time;

What about the 1.76FDD in the A4000. Is that "safe" to use with 1.44Mb HD floppies but to format them as 880K for games etc?


Should be OK as long as you cover the "extra" hole, otherwise it will try to read it as a 1.76mb disk.
Title: Re: 1.44 MB floppys used in 880K Amiga Disk Drives
Post by: kedawa on June 18, 2012, 10:01:35 PM
I modded my old PC's floppy drive with a switch that let me use old DD disks as HD disks, and never once had a problem with them.
I think if you have quality disks, they'll work fine regardless.
Title: Re: 1.44 MB floppys used in 880K Amiga Disk Drives
Post by: Megamig on June 19, 2012, 01:21:01 AM
Why would you bother with floppy discs these days?

Has anybody experimented with floppy disk emulators on their Amiga? If so, what brands? I know you can get ones that have been tested with the Amiga but I am curious if one can get away with using cheap PC alternatives?
Title: Re: 1.44 MB floppys used in 880K Amiga Disk Drives
Post by: Digiman on June 19, 2012, 06:36:43 AM
Because I have 100s of them and 4gb Amiga hard drives don't hold enough.
Title: Re: 1.44 MB floppys used in 880K Amiga Disk Drives
Post by: hooverphonique on June 19, 2012, 09:51:42 PM
Quote from: countzero;397930
AFAIK, the problem with the HD disks is the medium is different from DD disks and requires much more power to magnetise. This will eventually put a stress on your amiga floppy drive and one day kill it.

I'm positive that your drive will not be harmed the slightest by doing this..