Preserving Atari 8-bit disks

All questions about how to use KryoFlux go here.
User avatar
Mayhem
Posts: 229
Joined: Mon Apr 16, 2012 5:52 pm
Location: London, England
Contact:

Re: Preserving Atari 8-bit disks

Post by Mayhem » Sun Apr 05, 2015 3:50 pm

I'll chime in when I get the disks in question heh. But I use a Panasonic modded flippy JU-475-4 drive here.
Lie with passion and be forever damned...

fgasking
Posts: 17
Joined: Thu Mar 26, 2015 10:36 pm

Re: Preserving Atari 8-bit disks

Post by fgasking » Sun Apr 05, 2015 8:28 pm

Thanks very much for the very informative help IFW! I didn't realize that you could do format checks from the stream files, so i'll bear this in mind for the future once I get a modded drive.

I believe the disks are single sided and non-flippy. There are no notches cut into the disks and they were recorded onto using an Atari 600XL and a 1050 drive. The developer never seemed to use the flip side of their disks at all - with the C64 formatted ones also just being single sided. Of course, without getting the disks to read properly from here - I was unable to work out for certain what format they were - but the above seems to suggest single sided and non-flippy. Sounds like Mat's drive will be able to read them.

User avatar
IFW
Posts: 3079
Joined: Mon Nov 08, 2010 2:42 pm

Re: Preserving Atari 8-bit disks

Post by IFW » Tue Apr 07, 2015 12:17 pm

Yes, it should work fine.
As per another thread it would be probably a good idea to use DD mode during dumping and resort to HD mode on disks where DD failed.

fgasking
Posts: 17
Joined: Thu Mar 26, 2015 10:36 pm

Re: Preserving Atari 8-bit disks

Post by fgasking » Wed Sep 09, 2015 12:17 am

Sorry to resurrect this thread, but Mat Allen has very kindly started preserving the Atari disks, and 7 disks in total so far. The results are interesting, where one disk via DTC has managed to convert from its streamfiles (as guided earlier) to an .atx format using the -i3a flag. This disk contains Atari BASIC files.

The rest of the disks (which should contain C64 assembler code written on an Atari 600) suggest they are unformatted using the same flag. Trying all the different format flags gives similar results. The developer maintains that development was done using Atari 600 with a 1050 drive, but i'm wondering if there was something in-between which was formatting the disks ever so slightly different? The software or maybe a piece of development hardware that was being used.

I gave the a8rawconv converter a try over at http://atariage.com/forums/topic/231835 ... ity/page-1 to compare results, and this oddly manages to create a atx file for all the RAW files I chuck at it. But it reports 0 missing sectors, 0 phantom sectors and 720 sectors with errors for every disk image (apart from the one which the DTC converts perfectly).

Examining the errored ATX files clearly shows there is data there (which is promising), and I can even list the directories in the Altirra disk browser tool - but there is a lot of corruption and some images crash the disk browser tool. The consistent 720 errored sectors suggests to me that it may not actually be errors on the disk - but just adjustments needed to convert the RAW data into something that can be read in an emulator - though i'm probably wrong :)

It feels like we're close though!

If anyone might be able to take a look and give their opinion, that would be fantastic. As suggested earlier by IFW, I have attached the first 10 tracks of one of the images below - hope this is enough to give a flavor of what is going on.

http://www.gtw64.co.uk/dumps/atari-stream.zip

Feltzkrone
Posts: 255
Joined: Sat Jun 18, 2011 8:03 pm

Re: Preserving Atari 8-bit disks

Post by Feltzkrone » Wed Sep 09, 2015 6:58 am

Third-party upgrades for the 1050 (all add a true SSDD 180K capability)
... can be found here and one of those has probably been used:
http://www.atarimania.com/faq-atari-400 ... es_22.html

Image settings for command line usage:
  • -g0 -z1 -v288 -i4a
For GUI:
  • Image Type: MFM XFD, Atari 8-bit
  • Side Mode: Side 0
  • Sector Size: 256 Bytes
  • Target RPM: 288
I can't recall if 288 rpm is the default value for -i4a but defining it definitely won't harm. Additionally setting the track distance to 40 Tracks (-k2) and Sector Count to exactly 18 (-n+18) is possible but not really necessary.

User avatar
Mayhem
Posts: 229
Joined: Mon Apr 16, 2012 5:52 pm
Location: London, England
Contact:

Re: Preserving Atari 8-bit disks

Post by Mayhem » Wed Sep 09, 2015 10:52 am

Btw Istvan has said that -dd1 should be in the command line if the disks are DD, so I'll redump all the stream files using it, and see if we get anywhere then Frank :)

Oh, and having looked at the disks, a few of them DO have notches cut on the other side, so a few of them may have data on both sides. I shall see if I can indicate this in the filenames when I redump.
Lie with passion and be forever damned...

User avatar
IFW
Posts: 3079
Joined: Mon Nov 08, 2010 2:42 pm

Re: Preserving Atari 8-bit disks

Post by IFW » Wed Sep 09, 2015 10:57 am

I will take a look once Mat sends me the files.

fgasking
Posts: 17
Joined: Thu Mar 26, 2015 10:36 pm

Re: Preserving Atari 8-bit disks

Post by fgasking » Wed Sep 09, 2015 1:35 pm

Thanks everyone - hopefully that will be all it is.

Just a bit more info - but MAC65 was the assembler package that the developer used (which was cartridge based). Not sure if that means anything regarding the format as well, but the DD flag hopefully will be the only thing.

fgasking
Posts: 17
Joined: Thu Mar 26, 2015 10:36 pm

Re: Preserving Atari 8-bit disks

Post by fgasking » Fri Sep 11, 2015 6:42 pm

Progress! :)

DTC.exe -m1 -ffile.raw -i0 -g0 -z1 -n+18 -k2 -v288 -ffile.xfd -i4a

... Using some of the parameters that Feltzkrone suggests (thank you!) for about 6 of the disks seems to create a working XFD! One of the disks had SpartanDOS on it and booted into it perfectly. Then I was able to do a DIR on all the disks and see M65 and CBM files and proper file names :)

There were two things I weren't sure about. Firstly it steps up in 2 tracks due to the -k2 flag, trying -k1 makes every other track come up with either MFM: (unformatted) or MFM: (error) - so I assume -k2 is the correct way to go. Also Tracks 80 and 82 consistently across the 6 disks come up as MFM (Unformatted) - which I also assume is normal?

One of the disks was also a flippy image, so i've ran the same command above with -y and -g2 added. But its coming up with MFM unformatted - so I must be doing something wrong there?

Another 6 of the disks are all coming up as unformatted though ... I think they are either unformatted, or the transfer wasn't successful for the batch. The individual track raw sizes are very small in comparison to the ones that converted..
http://www.gtw64.co.uk/dumps/dump8.zip

User avatar
IFW
Posts: 3079
Joined: Mon Nov 08, 2010 2:42 pm

Re: Preserving Atari 8-bit disks

Post by IFW » Sat Sep 12, 2015 3:24 pm

dump8.zip only contains noise on the tracks. Either it's very dirty or the head might be dirty or it's unformatted/spent way too much time next a speaker etc.
If you can still read another disk without any problem, than the head is not dirty.
Try checking the disk surface to see if it has mould or does not look normal etc.
If yes, then clean it, if no, then unfortunately it's completely wiped...

Post Reply