Correct, my read process would not care what the format is, it would capture the data pulses regardless. It would then be up to the programs that I write in order to decode the format into data. It's a lot of work, but very rewarding when it is successful. Once the data pulses are properly captured, then they can be converted into the original bits at any time, once the format is decoded properly. A monumental task, at least it has been for me so far, but it seems to be working out quite well for all of the formats that I've tackled so far. I have not yet tackled MFM on QIC cartridges like this, so it sounds like a very interesting challenge, but it seems doable. I'm browsing the manual now, very good information. I'm seeing a 4-track system, with the track order <http://bitsavers.informatik.uni-stuttgart.de/pdf/dei/CMTD-3400S2_4tk6400bpi_1979.pdf#page=23> being the same as the Kennedy 6450, for which I have tapes, but no drive: http://microtechm1.blogspot.com/2015/09/kennedy-6450-tape-drive-data-format.... Anyway, I've successfully turned the pulses on all of those tracks into data with my programs, with only a few block errors that I'm working on painstakingly correcting. I see the MFM discussed between PDF pages 38-40 <http://bitsavers.informatik.uni-stuttgart.de/pdf/dei/CMTD-3400S2_4tk6400bpi_1979.pdf#page=38>. Section 4.5.1 seems to tell me exactly how to write my program to read this (as far as the data pulse interpretation). I'll need to look at that again later. So far this looks like a really good manual with lots of good technical data on the format. I wish I would have started my project with a manual that is this thorough or well organized. As far as transferring the data pulses to new tapes, well, I haven't built anything to do this yet, but it seems to me to be fairly straightforward to accomplish this. This is something I've wanted to do for myself for some time now. There are so many variables, and I'd have to tackle them one by one. This is actually something that I've discussed building with the assistance of Jim Drew, creator of the SuperCard Pro for floppy disks, and something I hope that I can accomplish in the not-so-distant future. Thanks for keeping this stuff alive. Maybe someday I can help you archive these very scarce and nearly extinct data/programs. More later, I hope. This is quite interesting for me, but I must sleep now. Check back with me soon on this, if you like, please. Thanks for the discussion, -AJ http://MightyFrame.com http://MicrotechM1.blogspot.com On Tue, Nov 17, 2015 at 2:25 AM, Oliver Lehmann via vcf-midatlantic < vcf-midatlantic@lists.vintagecomputerfederation.org> wrote:
Hi,
yeah - had also contact with Mattis in the past about his tapes. He also currently no way in backing up his tapes.
Even if the tapes are fit into QIC-11 tape drives, just remember that no regular QIC tape will be able to read them.
They are MFM encoded.
Here you'll find the manual of the drive used in the S8000 http://www.bitsavers.org/pdf/dei/CMTD-3400S2_4tk6400bpi_1979.pdf
Attached you'll find a text file I gathered from somewhere stating that it is the service manual of the drive. You'll see that its "features" are a bit of from QIC standard - it was made in a time where QIC wasn't that popular.
But maybe you're backing up strategy with a logic analyzer does not care about all that? I wonder how the recorded data could be then possibly restored on other tapes to create a copy for example?
Microtech Dart <microtechdart@gmail.com> wrote:
Speaking of rare QIC tapes, I've undertaken quite an effort to read
previously unreadable or unknown QIC tapes:
Soon, I'll do a video demonstration of the programs I wrote which read the data from the logic analyzer captures.
I'm pretty excited about the success of this project.
Also, maybe on topic here, I was also dialoguing with MattisLind from Sweden about preserving some rare Zilog 8000 Zeus OS tapes, where he doesn't have any hardware that will read them.
He asked if I was going to come to any of the Infoage/MARCH events such as Festivus, and that's where we left the conversation off. It would be a shame if he came with the tapes all the way from Sweden, and I missed him.
On Tue, Nov 17, 2015 at 1:55 AM, Oliver Lehmann via vcf-midatlantic < vcf-midatlantic@lists.vintagecomputerfederation.org> wrote:
Evan Koblentz via vcf-midatlantic < vcf-midatlantic@lists.vintagecomputerfederation.org> wrote:
I hope that it is ok that I signed on to your list. I am from germany
Welcome!
and I'm looking for information about the Zilog System 8000. I know that
you owned at least one in the past. I don't know if you still have it,
but I hope so :)
We have it, but we haven't done much with it. Perhaps at our next repair event. We have workshops here every few months.
Ok, I'll look forward to that - hoping that it will happen some day ;)
Just remember the tapes are quite rare and need be handled with care. Your tape drive has also a capstan which went to goo over the past 30 years, so please do not just put them into the drive without fixing that first.
Otherwise the tapes and their contents will be gone forever....
Regards, Oliver
--
Thanks, -AJ http://MicrotechM1.blogspot.com
-- Thanks, -AJ http://MicrotechM1.blogspot.com