Re: Floppy Disk Images
On 8/11/17 10:58 AM, Marvin Johnston via cctalk wrote: I have probably at least 10,000 floppy disks of many flavors (formats, hard sector, soft sector, various TPI and Tracks/disk, 3.5"/5.25?/8", etc.) I've been thinking about this, and you need to organize what you want to read and get this down to something you can do in your lifetime. I'm guessing I've only read a few thousand disks in fifteen years. I think the fastest I've processed a disk was still around 5 minutes a disk. It can quickly go much higher if any work has to be done on the physical media and especially if there are media retrys. The problem will be the workflow. If you are really lucky, you might be able to get a few systems running in parallel but in practice they need to be watched and the heads cleaned frequently. I can only stand doing this for maybe a week or two of full-time work at a reading station. The fastest way to deal with metadata is bundling like media types together, put a reference number near the label, scan the disk label (and things like paper directory listings) on a flatbed, use that number for the file name, do a batch, rinse lather repeat. If you're using Imagedisk, don't bother adding the tag when you read it, reconcile it with the scanned label in batches later, if at all. I do the reading on a separate machine from where the data is archived and shuttle it over on a thumb drive, then put the scans and images together into directories by project/system name number date. Then after I can't stand dealing with reading disks any more, I reconcile what I've done that day (or past couple of days)
Re: Floppy Disk Images
I've got the Cromemco WDI and WDI-II S100 controllers for both the 8" 7xxx series and the 5" 5xxx series if they're of any use to you; as with most Cromemco stuff the documentation is also available. If they're in fact Cromemco formatted there shouldn't be a problem, assuming they still work; if they're from a Corvus box it might be more challenging. m - Original Message - From: "Al Kossow via cctalk" To: Sent: Friday, August 11, 2017 4:58 PM Subject: Re: Floppy Disk Images > > > On 8/11/17 12:12 PM, Mattis Lind via cctalk wrote: > >> There is a very nice MFM-emulator by David Gesswein. > > It works very well. I've dumped several hundred 5" drives with it > which resulted in added support for many different controllers in > his decoder. > > 8" shugart interface drives are rising on the list of importance for > me. I've got several dozen with things that need to be imaged > and a bunch of IMI drives which I'm less hopeful of because of > their funky interface. > > >
Re: Floppy Disk Images
On 8/11/17 12:12 PM, Mattis Lind via cctalk wrote: > There is a very nice MFM-emulator by David Gesswein. It works very well. I've dumped several hundred 5" drives with it which resulted in added support for many different controllers in his decoder. 8" shugart interface drives are rising on the list of importance for me. I've got several dozen with things that need to be imaged and a bunch of IMI drives which I'm less hopeful of because of their funky interface.
Re: Floppy Disk Images
On 08/11/2017 10:58 AM, Marvin Johnston via cctalk wrote: > I seem to recall this topic has been brought up a couple of times > over the past 20 years or so that ClassicCmp has been in existance, > but I can't find the info. And technology has advanced :). > > I have probably at least 10,000 floppy disks of many flavors > (formats, hard sector, soft sector, various TPI and Tracks/disk, > 3.5"/5.25?/8", etc.) My most pressing/interesting issue is both > Polymorphic and Lobo Drives/Systems 5.25" and 8" disks. I don't think a solution exists to make real copies of *any arbitrary* floppy. Even the idea of two drives powered off the same motor, aligning index holes, etc. will not work. The reason is quite simple--on a low level, what you read from a floppy is not what was written. There are issues that crop up during writing a floppy, such as bit shift and crowding that must be compensated for--and it's very, very difficult to do this on a "blind" basis without knowing something about the format. This, after all, is what "write precompensation" is all about--an intentional distortion of the write process to ensure that reading looks more or less normal. And this isn't dealing with various copy-protection schemes, special-purpose replacement drive electronics boards (they exist) and varying track densities (48, 96, 100, 135, 67.5 tpi) as well as the real oddball stuff, such as Kodak/Drivetec floppies. I recently ran into a floppy drive used on a CNC controller that has an utterly non-standard track spacing--the manufacturer included in their PLC solely for reading a disk of proprietary software--i.e. the PLC has *two* floppy drives; one standard and the other just for those floppies. I use a Catweasel to image my floppies--it does the job well, but so will any decent modern microcontroller with a timer "capture" function. --Chuck
Re: Floppy Disk Images
On Fri, Aug 11, 2017 at 12:08 PM, Christian Groessler via cctalk < cctalk@classiccmp.org> wrote: > Hi, > > On 08/11/17 19:58, Marvin Johnston via cctalk wrote: > >> And just to make it interesting, I have a number of hard disks (5mb to >> maybe 20mb) of both 5.35" and 8". I've got several Lobo drives 8" hard >> drives that I would love to get the information from since they came from >> Lobo Drives when they shut down. Controllers could be a problem there. > > I love kyroflux for the 300 rainbow floppies I just did. But you'll need a supported drive, and the more exotic formats are dicier on main-stream drives, though even the flippies work. And you can store it as flux transitions, raw track data or arrays of sectors when reading data. I thought I'd need that for the rainbow disks, but only the 123 disks had any kind of odditiy as copy protection, but there's patches to cope with that. > a related question (wanted to ask since long, but this post reminded me > now): > > Is there a similar tool like IMD to dump (MFM-) hard disks? > There's a MFM emulator that also reads MFM hard disks. https://www.pdp8.net/mfm/mfm.shtml is what I've used to image a couple of MFM hard disks that I have. It also emulates MFM drives, which makes it easy to switch between Venix and MS-DOS on my Dec Rainbow. Warner
Re: Floppy Disk Images
fredag 11 augusti 2017 skrev Christian Groessler via cctalk < cctalk@classiccmp.org>: > > > > a related question (wanted to ask since long, but this post reminded me > now): > > Is there a similar tool like IMD to dump (MFM-) hard disks? There is a very nice MFM-emulator by David Gesswein. It not only is able to emulate the disk but also read out the content. If there already is a decoder you can get the decoded sectors as a dump, otherwise you need to process the raw transitions yourself. I have had success reading and emulating DEC RQDX1/ RQDX2 as well as Cromemco STDC format with the mfm emulator. David is also very quick to help out when you encounter problems. https://www.pdp8.net/mfm/mfm.shtml > regards, > chris > > /Mattis
Re: Floppy Disk Images
Hi, On 08/11/17 19:58, Marvin Johnston via cctalk wrote: And just to make it interesting, I have a number of hard disks (5mb to maybe 20mb) of both 5.35" and 8". I've got several Lobo drives 8" hard drives that I would love to get the information from since they came from Lobo Drives when they shut down. Controllers could be a problem there. a related question (wanted to ask since long, but this post reminded me now): Is there a similar tool like IMD to dump (MFM-) hard disks? regards, chris
