Corrupted images?

All questions about how to use KryoFlux go here.
Post Reply
MrJW
Posts: 5
Joined: Sat Nov 05, 2011 5:42 pm

Corrupted images?

Post by MrJW » Tue Nov 15, 2011 12:07 am

Today I tried dumping PC (MS-DOS) disks as a test for the first time. Unfortunately I only get corrupted images.
I use the Java GUI-tool to create my images and I have set it up as shown in the attachment. The first 2 tracks are reported succesful, but the next 166 tracks are not being recognized and are labeled unknown.
When I open the dumped images using Winimage I can see the files / folders and believable file sizes (looks like the FAT-table survives) but the files cannot be opened using DOSBox. DOSBox just hangs when opening them. Also text files contain garbage.
Calibrating using the GUI tool went okay and reported Calibration successful. Maximum track for drive is: 83.
Dumping results are the same for the standard firmware and the slow firmware.
Screenshot when finished dumping a standard MS-DOS formatted disk. Lots of unknown tracks.
Screenshot when finished dumping a standard MS-DOS formatted disk. Lots of unknown tracks.
kryoflux-dump_unknownTracks.PNG (50.63 KiB) Viewed 1292 times
Dumping of a test disk using kryoflux (does not contain valueable data).
Dumping of a test disk using kryoflux (does not contain valueable data).
WinImg_DiskContents.PNG (21.63 KiB) Viewed 1291 times
I am using the kryoflux together with a Panasonic JU-475-3BGM 5.25" drive.
I connected the kryoflux to the pc directly (no USB hubs used as I do not have one). To connect it to the pc I first used a standard USB A to USB B cable. When that only give me the corrupted images I tried it with a different USB cable which has 2x USB A to USB B. This cable has an additional USB connector to provide a higher current for devices that require more than the default 500 mA a USB port can deliver.

TeaRex
Posts: 120
Joined: Tue Nov 30, 2010 5:36 am

Re: Corrupted images?

Post by TeaRex » Tue Nov 15, 2011 3:54 am

Did you try connecting that same floppy drive directly to a PC motherboard? Were the disks readable that way? (try something like chkdsk /r to read the whole surface, if you're on a Windows machine)

KryoFlux should run on a standard PC USB port (no need for an Y cable). But the floppy drive NEEDS ITS OWN POWER. You can't power it "through" KryoFlux via a standard USB port. So connect the floppy to either your PCs own power supply or an external PSU such as that sold with the KryoFlux premium edition. You could also use an old PC-AT power supply, or an ATX power supply if you short the "power switch" pins.

MrJW
Posts: 5
Joined: Sat Nov 05, 2011 5:42 pm

Re: Corrupted images?

Post by MrJW » Tue Nov 15, 2011 2:02 pm

Thanks for your reply TeaRex.
I did not try the drive connected to the motherboard of a normal pc. A least not for a long time.
I forgot to mention that the drive was powered directly by a 5 / 12V (2 A) powersuplly intended to use with harddisks or standard size optical drives the whole time. I know floppy drives require both 5V and 12 V input with a decent current to operate. The powersupply was not connected to the KryoFlux board, but only to the drive. The KryoFlux board was only connected to the 34 pin connector and USB cable. I strictly followed the steps outlined in the supplied quickstart manual.
At first I used a normal USB cable, like the one that was shipped with the KryoFlux board. After that I tried the Y cable.
Do you expect the dumping result comes from a shortage of power to the drive? If I look and hear the drive it seems that it works okay. The diskdrive's LED is brightly lid and the motor seems to spin up just nicely.

TeaRex
Posts: 120
Joined: Tue Nov 30, 2010 5:36 am

Re: Corrupted images?

Post by TeaRex » Tue Nov 15, 2011 7:24 pm

I don't think you have a drive power problem then.

Do try the drive with a PC motherboard. Maybe it's just misaligned. KryoFlux can't read your disks if the drive itself is problematic. Rule of thumb: mechanics fail more often than electronics.

User avatar
karadoc
Posts: 138
Joined: Sun Oct 31, 2010 9:12 pm

Re: Corrupted images?

Post by karadoc » Tue Nov 15, 2011 9:28 pm

I'd basically echo what TeaRex has said. Since you seemed to have tried other disks, trying a different drive is your best bet.

One other possibility - is it possible those disks you tried were all written with the same misaligned drive? In that case, unless you have that original drive, you are probably out of luck...

Post Reply