USB Floppy Disk Device (Drive) with Support for Windows 10 and QPC2?

Discussion and advice about emulating the QL on other machines.
Martin_Head
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Re: USB Floppy Disk Device (Drive) with Support for Windows 10 and QPC2?

Post by Martin_Head »

tofro wrote: You cannot re-format a disk that was originally formatted on a DD drive on an HD drive. The tracks are wider on DD and a HD drive is not able to erase all of the information the DD drive has put on the disk. Such disks either need to be erased entirely using a (very) strong magnet or need to be re-formatted on a DD drive.
Are you sure? DD and HD 3.5" drives are both 80 tracks. The difference in capacity being the number of sectors per track.

Are you thinking of the old 5.25" disk drives? Where the tracks were narrower on HD drives than DD drives. one being 80 trace, and the other 40 tracks.

Also I don't think that the later QPC2's, (Version 4) Actually format the floppies any more. It just wipes the data on the existing sectors.

Martin Head


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tofro
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Re: USB Floppy Disk Device (Drive) with Support for Windows 10 and QPC2?

Post by tofro »

Martin_Head wrote:
tofro wrote: You cannot re-format a disk that was originally formatted on a DD drive on an HD drive. The tracks are wider on DD and a HD drive is not able to erase all of the information the DD drive has put on the disk. Such disks either need to be erased entirely using a (very) strong magnet or need to be re-formatted on a DD drive.
Are you sure? DD and HD 3.5" drives are both 80 tracks. The difference in capacity being the number of sectors per track.

Are you thinking of the old 5.25" disk drives? Where the tracks were narrower on HD drives than DD drives. one being 80 trace, and the other 40 tracks.

Also I don't think that the later QPC2's, (Version 4) Actually format the floppies any more. It just wipes the data on the existing sectors.

Martin Head
Not sure what's the reason, but I have made the experience that I cannot get a HD disk to properly format (in Windows) on a HD drive as DD when it was previously formatted by my original QL's DD drive (Even if my HD drives work reliably otherwise). Formatting it on the old QL makes that work again here, reliably.


And, yes, QPC (as of 4.0 and later) is not really low-level formatting the disk - It does not wipe the data on the existing sectors, though, just empties the directory and map, apparently (the process is just way too fast for really touching all the sectors).
QPC Manual wrote:As of version 4 QPC does not physically format floppy disks anymore. The disk must already have been formatted by Windows or any other means. Formatting the disk in QPC only writes the SMSQ/E file system to it.
(And I guess that makes quite a number of statements in the current QPC manual obsolete that still seem to be referring to physical formatting of the disk.)


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Re: USB Floppy Disk Device (Drive) with Support for Windows 10 and QPC2?

Post by RWAP »

Formatting HD disks as DD disks has always been problematic and unreliable when switching between disk drives.

I have no idea why - but that is why I would never recommend that anyone format a HD disk as DD even if they cover up the HD detection hole.


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Re: USB Floppy Disk Device (Drive) with Support for Windows 10 and QPC2?

Post by Cristian »

tofro wrote: You cannot re-format a disk that was originally formatted on a DD drive on an HD drive.
I can't understand which type of floppy drive you're talking about. The normal 3.5" PC floppy drives have always formatted DD and HD disks in HD and DD and vice versa: you only need to cover/make the floppy hole.
Right now I'm formatting on my PC (Windows) a DD QL disk to 1.44 MB (HD)..... format successful, as usual.
The same result also with my external USB floppy drive.


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Re: USB Floppy Disk Device (Drive) with Support for Windows 10 and QPC2?

Post by Cristian »

RWAP wrote:Formatting HD disks as DD disks has always been problematic and unreliable when switching between disk drives.
I have no idea why
Could you please specify what exactly do you mean with "problematic and unreliable"? I've been using and formatting only hole-covered HD disks to Qdos DD (TrumpCard) for years and yes, many have been used for 20-30 years and a percentage of them sometimes fails.
Last edited by Cristian on Mon Nov 21, 2016 9:55 pm, edited 1 time in total.


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tofro
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Re: USB Floppy Disk Device (Drive) with Support for Windows 10 and QPC2?

Post by tofro »

Cristian wrote:
tofro wrote: You cannot re-format a disk that was originally formatted on a DD drive on an HD drive.
I can't understand which type of floppy drive you're talking about. The normal 3.5" PC floppy drives have always formatted DD and HD disks in HD and DD and vice versa: you only need to cover/make the floppy hole.
Right now I'm formatting on my PC (Windows) a DD QL disk to 1.44 MB (HD)..... format successful, as usual.
The same result also with my external USB floppy drive.
I am talking about HD drives in a Q40, a USB (HD) Fuji Floppy drive, and a set of relatively new twin HD drives (courtesy Ben Versteeg) for my Gold/SuperGold cards. None of these works reliably reformatting (DD) a DD disk that was originally formatted on my old QL SuperQBoard floppy drives. Formatting them on the QBoard set makes them 100% reliable on the other drives for both reading and writingl, though.

Tobias


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Re: USB Floppy Disk Device (Drive) with Support for Windows 10 and QPC2?

Post by Cristian »

tofro wrote: I am talking about HD drives in a Q40, a USB (HD) Fuji Floppy drive, and a set of relatively new twin HD drives (courtesy Ben Versteeg) for my Gold/SuperGold cards. None of these works reliably reformatting (DD) a DD disk that was originally formatted on my old QL SuperQBoard floppy drives. Formatting them on the QBoard set makes them 100% reliable on the other drives for both reading and writingl, though.

Tobias
OK, so you were referring to your specific hardware combination. Thanks for your clarification.
Well, at least Peter fortunately will not be affected by these difficulties since - as it emerges - he's working with normal Windows/QPC2 floppy drives


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Re: USB Floppy Disk Device (Drive) with Support for Windows 10 and QPC2?

Post by RWAP »

Cristian wrote:
RWAP wrote:Formatting HD disks as DD disks has always been problematic and unreliable when switching between disk drives.
I have no idea why
Could you please specify what exactly do you mean with "problematic and unreliable"? I've been using and formatting only hole-covered HD disks to Qdos DD (TrumpCard) for years and yes, many have been used for 20-30 years and a percentage of them sometimes fails.
It is hard to be exact - it has just been my experience that if you format a HD disk in a DD disk drive and then try to read it in another drive (maybe a HD disk drive), it is not always recognised as properly formatted - whether you have covered the HD detect hole or not.

If you use the same drive (and/or possibly the same interface), then there should not be an issue.

There are also issues in SMSQ/e - for example, many years ago, I created my own small utility for testing disks and trying to figure out this sort of problem.

Unfortunately, whilst FLP_DENSITY 'h' and FLP_DENSITY 'e' worked, when I tried to switch to FLP_DENSITY 'd' - I always got format failed and had to throw the disk away as it would not then re-format in any density (I think I was testing using HD disks as DD at the time but it was years ago so I am not certain).


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Re: USB Floppy Disk Device (Drive) with Support for Windows 10 and QPC2?

Post by Cristian »

RWAP wrote: If you use the same drive (and/or possibly the same interface), then there should not be an issue.
There are also issues in SMSQ/e
(I think I was testing using HD disks as DD at the time but it was years ago so I am not certain).
Thanks for your explanation.
Anyway, this doesn't seem a general issue but sounds like a matter of unlucky hardware/software combination.
Indeed I did (and I'm doing) many operations with DD and ED disks, formatted with TrumpCard, PC Windows, QemuLator (and also ZX PlusD), many different floppy drives (also external USB) and, if I respect the "rule of the detection hole", all disks can always be swapped in the various combinations.
Sometimes certain older disks are affected by some read/write failing, but in most cases they are reformattable.
I'm thinking about the possible hardware problem: maybe it can be focused on the fact I utilize only PC floppy drives? Maybe they are more reliable or compatible? I don't know.


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Re: USB Floppy Disk Device (Drive) with Support for Windows 10 and QPC2?

Post by Martin_Head »

I may be wrong about this, but I think that DD and HD disks had a different magnetic coating. And the floppy drive had to use a different recording current for the write head, depending on the disks type.

So if you start covering up the holes in the disk to fool the drive into thinking the disk is of a different type, the disk will be recorded with the wrong magnetic strengths. So whether the disk will work, depends on the quality of the disk/drive.

Martin Head


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