retrobrad
does anyone know how to fix up an amiga disk?
Goto page Previous  1, 2
 
Post new topic   Reply to topic    retrobrad Forum Index -> All about Amiga!
View previous topic :: View next topic  
Author Message
Misha
intermediate
intermediate


Joined: 04 Jul 2007
Posts: 234
Location: North Wales

PostPosted: Tue Aug 28, 2007 5:20 am    Post subject: Reply with quote

First of all if you have a blank Amiga disk this can be formatted as a 720k PC floppy if you set up your Amiga as directed in the previous post,that way you can use the floppy in your PC,download Disksalv 2 to the floppy and then put into your amiga.

Never wanted you to erase your KIN disk but make a copy of your KIN disk before using Disksalv 2
Back to top
View user's profile Send private message
retrobrad
Administrator
Administrator


Joined: 08 Jun 2007
Posts: 1039
Location: NSW, Australia

PostPosted: Tue Aug 28, 2007 5:22 pm    Post subject: Reply with quote

Misha wrote:
First of all if you have a blank Amiga disk this can be formatted as a 720k PC floppy if you set up your Amiga as directed in the previous post,that way you can use the floppy in your PC,download Disksalv 2 to the floppy and then put into your amiga.

Never wanted you to erase your KIN disk but make a copy of your KIN disk before using Disksalv 2


oh i got it now Wink

i thought you meant format the KIN disk and then somehow magically copy it (even though it has just been erased!) Shocked
Back to top
View user's profile Send private message Send e-mail
retrobrad
Administrator
Administrator


Joined: 08 Jun 2007
Posts: 1039
Location: NSW, Australia

PostPosted: Thu Aug 30, 2007 12:46 pm    Post subject: Reply with quote

sorry guys, i still just havent had the time to try any of your disk fix tips, but ill get around to it by the end of the week!
Back to top
View user's profile Send private message Send e-mail
retrobrad
Administrator
Administrator


Joined: 08 Jun 2007
Posts: 1039
Location: NSW, Australia

PostPosted: Sun Sep 02, 2007 3:50 pm    Post subject: Reply with quote

okay well i ran it through x-copy a few times and seems to have worked but guess what?!!!!

someone had copied over the game! it's not KIN at all but it's 1943!!!!
Back to top
View user's profile Send private message Send e-mail
Misha
intermediate
intermediate


Joined: 04 Jul 2007
Posts: 234
Location: North Wales

PostPosted: Tue Sep 04, 2007 4:22 am    Post subject: Reply with quote

Oh dear....why replace a rare game with "1943"? the Disksalv 2 thing might still work to recover the original disk but i guess it will only be a partial recovery Sad it`s worth a try brad and will only work if the disk hasn`t been formatted to many times otherwise you`ll never get KIN back.

Hope someone has a copy for ya because it would be a nice one to add to the colly,let us know if you manage to recover the original game!! failing that do me a disk image and e-mail to me and i`ll spend hours and hours to see if i can recover for you.
Back to top
View user's profile Send private message
retrobrad
Administrator
Administrator


Joined: 08 Jun 2007
Posts: 1039
Location: NSW, Australia

PostPosted: Tue Sep 04, 2007 6:51 pm    Post subject: Reply with quote

Misha wrote:
Oh dear....why replace a rare game with "1943"? the Disksalv 2 thing might still work to recover the original disk but i guess it will only be a partial recovery Sad it`s worth a try brad and will only work if the disk hasn`t been formatted to many times otherwise you`ll never get KIN back.

Hope someone has a copy for ya because it would be a nice one to add to the colly,let us know if you manage to recover the original game!! failing that do me a disk image and e-mail to me and i`ll spend hours and hours to see if i can recover for you.


yeah it gets me???

can you really recover a disk from a disk image????
Back to top
View user's profile Send private message Send e-mail
Misha
intermediate
intermediate


Joined: 04 Jul 2007
Posts: 234
Location: North Wales

PostPosted: Wed Sep 05, 2007 5:28 am    Post subject: Reply with quote

Yeah you should be able to,can`t say i`ve ever tried it but it`s worth a shot if the end result is you get the original game back,if you got time then give it ago,at this stage anything is worth a try Very Happy
Back to top
View user's profile Send private message
retrobrad
Administrator
Administrator


Joined: 08 Jun 2007
Posts: 1039
Location: NSW, Australia

PostPosted: Wed Sep 05, 2007 12:09 pm    Post subject: Reply with quote

Misha wrote:
Yeah you should be able to,can`t say i`ve ever tried it but it`s worth a shot if the end result is you get the original game back,if you got time then give it ago,at this stage anything is worth a try Very Happy


im not too sure that you can though - (from my understanding of how floppy disks work)

each bit in a disk is either magnetised (for a '1') or demagnitised (for a '0') and the way that you can get back previously erased data is that the special recovery software looks for residual magnetism left there after this disk was erased / copied over.

but if you just copy a disk image, i dont think it would get both the actual data and the 'old' data...

but then again i have never tried - has anybody managed to do this?
Back to top
View user's profile Send private message Send e-mail
Misha
intermediate
intermediate


Joined: 04 Jul 2007
Posts: 234
Location: North Wales

PostPosted: Thu Sep 06, 2007 6:18 am    Post subject: Reply with quote

I got to admit i`ve only ever recovered an original disk after it`s been formatted only once with Disksalv so i won`t argue the fact,you may well be right about the disk image to as i`ve never tried it from an image,surely it`s possible though because when you copy a disk into adf format to run games on WinUAE it copies the whole contents of the disk.

Like i`ve already said i`ve never tried this method but you have the disk so i can`t see why you can`t recover it or at least try.
Back to top
View user's profile Send private message
Rybags
beginner
beginner


Joined: 03 Oct 2007
Posts: 26

PostPosted: Thu Nov 08, 2007 11:07 pm    Post subject: Reply with quote

You can read Amiga floppies with a PC drive.

The trick involves some software and you need two floppy drives installed.

It uses the second drive for timing, and works by quickly changing which drive the controller is talking to.

I tried it and it worked, but was a bit cumbersome and barely quicker than using something like DOS2DOS and TRANDISK on an Amiga.

I don't have the link here, but some searching should reveal it.
Back to top
View user's profile Send private message
blade002
intermediate
intermediate


Joined: 30 Sep 2007
Posts: 113

PostPosted: Thu Nov 08, 2007 11:33 pm    Post subject: Reply with quote

Misha wrote:
First of all if you have a blank Amiga disk this can be formatted as a 720k PC floppy if you set up your Amiga as directed in the previous post,that way you can use the floppy in your PC,download Disksalv 2 to the floppy and then put into your amiga.

Never wanted you to erase your KIN disk but make a copy of your KIN disk before using Disksalv 2


Just to clarify something here. Amiga disks format at 880k and if you have a 1 disk Amiga program it will not work with a disk formatted at 720k. Formatting at 720k to make the disk PC0: not DF0: is really only good for transfering small packets of data over to the Amiga such as a MOD, some Jpeg's..etc.
Back to top
View user's profile Send private message
Azryl
beginner
beginner


Joined: 25 Oct 2007
Posts: 26
Location: Melbourne Australia

PostPosted: Fri Nov 09, 2007 5:13 pm    Post subject: Reply with quote

Wow.. some of the advice given in the above posts is WAY WRONG!

first up... if you copy new track or sector info over the old track/sector info... that information is overwritten... ie the original information stored in that part of the amiga disk is gone forever.

But.. if you accidentally quick formatted an Amiga 880k disk all the quick fomat does is write blank disk information into track 40 under AmigaDOS effectively making the disk seem new and empty and just formatted. But it leaves all the orginal sector information physically intact on the disk tracks 0-39 41-79 etc only modifying track 40 which keeps all the filesystem information and disk name etc.

Using a program like DiskSalv you can get all the orginal information back into the track 40 of AmigaDOS by reading all the the tracks and rebuilding the track 40 file/directory information. Takes a long time, but its possible and yes I have done this a few times so I know it works.

OK.. the wrong things people have given advice about is the use of PC formatted 720k floppy... nope... you cannot use a PC 720k format to recover amiga files... competely different track/sector/header information in a different physical layout on the disk surface.

The Amiga chip Paula which handles the physical track reading writing is capable of understanding an amazing array of different DOS types written to the standard 1meg 3.5inch floppy disk. Each of these different file formats are understood within the AmigaOS through its underlying "trackdisk.device" structure which means one physical device can be used by multiple trackdisk.devices to allow different floppy formats to be read by the associated file systems. Oldfilesystem, Fastfilesystem, PCdos etc which means you can have on the workbench screen DF0: and PC0: and you can now understand what is written on each type of disk and even copy files between them. The underlying trackdisk.device system does all this automatically for you.

But the differences of the disk layout and sectors means they cannot be used to recover lost information from a different DOS type. Some of the Amiga trackdisk information or floppy devices used could also be in a different media encoding.. from MFM to GCR is possible with the Amiga.

The only reliable way to get past read errors on a physcial floppy disk is to use 2 floppy drives, one to constantly re-read the damaged track and hopefully gleam a little more information each pass and then write this collected information onto the second drive as a clone of the damaged track information but now rebuilt into a good track source. Some of the more capable disk recovery software could rebuild the track from a known list of possible track errors and nibble read the parts of the encoded information between the sector and track header/end gap information.

Please remember that original floppy games had INTENTIONAL errors on the disk to stop software piracy. So the error is meant to be found on that track when the disk is being loaded or at preset times during the gameplay to make sure the user had an original disk.

Hope that helps

Az
Back to top
View user's profile Send private message Visit poster's website
blade002
intermediate
intermediate


Joined: 30 Sep 2007
Posts: 113

PostPosted: Fri Nov 09, 2007 7:18 pm    Post subject: Reply with quote

Azryl wrote:
Wow.. some of the advice given in the above posts is WAY WRONG!

first up... if you copy new track or sector info over the old track/sector info... that information is overwritten... ie the original information stored in that part of the amiga disk is gone forever.

But.. if you accidentally quick formatted an Amiga 880k disk all the quick fomat does is write blank disk information into track 40 under AmigaDOS effectively making the disk seem new and empty and just formatted. But it leaves all the orginal sector information physically intact on the disk tracks 0-39 41-79 etc only modifying track 40 which keeps all the filesystem information and disk name etc.

Using a program like DiskSalv you can get all the orginal information back into the track 40 of AmigaDOS by reading all the the tracks and rebuilding the track 40 file/directory information. Takes a long time, but its possible and yes I have done this a few times so I know it works.

OK.. the wrong things people have given advice about is the use of PC formatted 720k floppy... nope... you cannot use a PC 720k format to recover amiga files... competely different track/sector/header information in a different physical layout on the disk surface.

The Amiga chip Paula which handles the physical track reading writing is capable of understanding an amazing array of different DOS types written to the standard 1meg 3.5inch floppy disk. Each of these different file formats are understood within the AmigaOS through its underlying "trackdisk.device" structure which means one physical device can be used by multiple trackdisk.devices to allow different floppy formats to be read by the associated file systems. Oldfilesystem, Fastfilesystem, PCdos etc which means you can have on the workbench screen DF0: and PC0: and you can now understand what is written on each type of disk and even copy files between them. The underlying trackdisk.device system does all this automatically for you.

But the differences of the disk layout and sectors means they cannot be used to recover lost information from a different DOS type. Some of the Amiga trackdisk information or floppy devices used could also be in a different media encoding.. from MFM to GCR is possible with the Amiga.

The only reliable way to get past read errors on a physcial floppy disk is to use 2 floppy drives, one to constantly re-read the damaged track and hopefully gleam a little more information each pass and then write this collected information onto the second drive as a clone of the damaged track information but now rebuilt into a good track source. Some of the more capable disk recovery software could rebuild the track from a known list of possible track errors and nibble read the parts of the encoded information between the sector and track header/end gap information.

Please remember that original floppy games had INTENTIONAL errors on the disk to stop software piracy. So the error is meant to be found on that track when the disk is being loaded or at preset times during the gameplay to make sure the user had an original disk.

Hope that helps

Az


Couldn't have said it better myself Azryl, because i just didn't have time Smile

And also very true about the intentional on errors on disks from software publishers, which could be evidently seen when copying cracked games back in the 90's on X-Copy. On particular sectors at times you would see it struggling to read them, and without using the verify option some would not do a proper full copy at ALL !!. ( and nope, i am not thinking of bad sectors on a disk, in regards to this )

Catchya Smile
Back to top
View user's profile Send private message
Display posts from previous:   
Post new topic   Reply to topic    retrobrad Forum Index -> All about Amiga! All times are GMT + 10 Hours
Goto page Previous  1, 2
Page 2 of 2

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum


Powered by phpBB © 2001, 2002 phpBB Group
Style Distributed by Olate