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128K/180K PC 5.25" Floppys.

Posted: Sun Feb 19, 2017 11:23 am
by Icon
Hi!
I have search the forum and reed all the post relevant to my questions but havent found any answare. If I have missed some and this is already solved in another thread, I am sorry for double post.
Im using Kryoflux.
I have two questions:

1) I havent figure out how to dump 128K 5.25" PC floppys. Anyone have any idea how to do that either from the UI or the command prompt? Same Problem with 180K floppys.

2) How do I dump 80 track PC disks that are spread out on boths sides (40 Track on each side)? On halv of the side is data and the other is "gray" unformatted sectors? The Images comes out corrupted on these type of floppys.
Like this:
Image
Thanks in advance,
Icon (Mike)

Re: 128K/180K PC 5.25" Floppys.

Posted: Sun Feb 19, 2017 12:00 pm
by brightcaster
Well, that looks right for me. What did you excpect?

If you only have 40 tracks on one side you can only read 40 tracks and the rest should be grey! The same happens if you have 80 tracks and tracks 81 to 83 are grey...

Regards, David

Re: 128K/180K PC 5.25" Floppys.

Posted: Sun Feb 19, 2017 2:48 pm
by SomeGuy
128k?

The standard formats on IBM PC low-density MFM 5.25" disks are:
160k (Single Sided Double Density, 8 sectors per track, DOS 1.0)
320K (Double Sided Double Density, 8 sectors per track, DOS 1.1)
180k (Single Sided Double Density, 9 sectors per track, DOS 2.0)
360K (Double Sided Double Density, 9 sectors per track, DOS 2.0)

Of course, some "booter" games and copy protected titles may have their own weird formats.

When dumping a MFM sector image, the resulting file size should match the disk size. If it does not, then you may need to instruct the Kryflux to limit itself to reading a maximum number of heads, tracks, and/or sectors. In the GUI you can achieve this by making a copy of the "MFM Sector Image", specify the needed parameters, and save it to something like "MFM Sector Image 160k"

Note that images from disks formatted under DOS 1.x may not open in tools like WinImage.

In many cases, it is preferable to store such disks as ImageDisk format instead. You should be able to use the HxC software to convert a kryoflux preservation stream directly to ImageDisk.

Also, you should use the "Calibrate" option in the menu to set the maximum number of tracks your drive can handle (around 42 on a low density 5.25" drive). Otherwise you wind up banging the head against the stop

Re: 128K/180K PC 5.25" Floppys.

Posted: Sun Feb 19, 2017 3:12 pm
by Icon
Thank you guys for quick response. I was a little unclear maby. I DID expect the result I shown in the screendump, but I cant open the .img file in HxC software or any other software. It just says its a corrupt image. In the example (world Games) there seems to be a copyprotection in track 1.0 so that can explain it in that case but I get the same result with all the other floppys that looks the same (except for the copy protection).

SomeGuy: The example you see inte screenshot, is that a 320K or 360K? Maby one can not tell that just by the graphical sectormap? When I dump "world games" its 40 Tracks on both sides I get 720K and the .img file is just a "NULL size disc" according to Hxc.

Re: 128K/180K PC 5.25" Floppys.

Posted: Mon Feb 20, 2017 7:37 am
by ZrX
It looks to be a doublesided (non-flippy) 40-track disk written on 80-track drive.

You just need to set the last track to 39.

In theory a disk image of random size should still list the contents in WinImage and such if the directory exists at correct location.

Can you upload the raw files somwhere to check?

Re: 128K/180K PC 5.25" Floppys.

Posted: Mon Feb 20, 2017 8:32 am
by Icon
Thank you! :-)

I have enclosed two different titles with the same problem (Oil barons a 5.25" DOS floppy and World Games a 3.5" DOS floppy).

https://ufile.io/189151

/Icon

Re: 128K/180K PC 5.25" Floppys.

Posted: Mon Feb 20, 2017 8:45 pm
by ZrX
These were both 5.25" floppies with original looking labels?

The World Games disk looks like a PC disk but as if something has damaged some vital part of it.

Both Oil Barons disks look like regular DOS disks with only multiple .BAS-files on them.

Edit:
After googling a bit, both are DOS-games. Oil Barons requires GWBasic, and World Games MIGHT be a "booter" but I'm unable to get it to work on either DOSbox or PCE. Found a version with the disk-image used as a file and a separate loader file to launch it.

Re: 128K/180K PC 5.25" Floppys.

Posted: Mon Feb 20, 2017 9:39 pm
by Icon
Both is from the original box. World Games is a 3.5" Dos disk. OilBarons is two 5_25" floppys.
How did you extract any files from them? I tried to create .img files with both Kryoflyx UI and HxC and both programs just created nullsized Dos-images.
It no biggie but I have more originals witch also are 40 Tracks and I faild to create .img files out of them aswell. So I thougt I did something wrong with just these kind of disks.

Re: 128K/180K PC 5.25" Floppys.

Posted: Tue Feb 21, 2017 4:11 am
by SomeGuy
World Games appears copy protected, and contains an intentionally "bad" sector on the first track. This means you will not be able to create a usable IMG file. You also appear to have dumped that disk in a 360k drive, but incorrectly specified to dump 80 tracks. It appears to be a "booter" with a non-DOS boot sector and no files to extract.

Oil Barrons contains two 160k floppy disk images that are formatted for DOS 1.x (which lacks PBP information used by most DOS disk tools). It looks like you dumped these using a 1.2mb floppy drive, which means the images must be decoded at 300KBS and with "double stepping". At a glance, they do not appear to be copy protected.

You can extract files from these by hex editing the boot sector and replacing the missing BPB information.

Code: Select all

160K: (163,840 bytes)
00000000  xx xx xx 49 42 4D 20 20-32 2E 30 00 02 01 01 00    .'.IBM  2.0.....
00000010  02 40 00 40 01 FD 01 00-08 00 01 00 00 00 00 00    .@.@............

Re: 128K/180K PC 5.25" Floppys.

Posted: Tue Feb 21, 2017 12:40 pm
by Icon
Thank you VERY much for the information. I have dumped hundreds of disks but feeling I am still learning, so the help is much appreciated. :-)

Ps. Can you in the UI tell it to decode in 300KBS?