ADF writing experience

All questions about how to use KryoFlux go here.
Post Reply
TeaRex
Posts: 120
Joined: Tue Nov 30, 2010 5:36 am

ADF writing experience

Post by TeaRex »

ADF writing is very cool, thanks a lot for your continued efforts with this beast. Now I no longer have to boot back and forth between Linux and Windows, creating IPFs from the ADFs with the Amiga-Disk-Utilities package on Linux, then writing them on Windows.

However I noticed that ADF writing has a tendendcy to fail - only one of my six 3.5" drives works correctly with this (not including the one I ordered from SPS together with my KryoFlux). All other drives tend to produce errors on the upper tracks, roughly track 65+, some only 70+, usually only on the front side of the disk (no idea why that would be so...). I don't mean I get errors during writing; I get errors during re-reading the written data, either on the same drive via KryoFlux's dtc -i5 or in a real Amiga 500's internal drive. Even the one drive that doesn't always have this problem has it with certain floppies, floppies that do work without a hitch when I write to them in the Amiga, and which are perfectly readable by KryoFlux when written to on the Amiga.

Of course I am using only real DD floppies for this. They are BASF/Emtec made and some years old but not ancient. The one drive that works best is a no-name combo drive which has a standard 34-pin floppy and a bunch of USB card readers (CF, SD, MemoryStick) in the same housing. I also noticed the problem seems to get worse when I use a shorter floppy cable and seems to get better when I use my longest cable.

Feel free to move this message if you want it somewhere else.

User avatar
mr.vince
Posts: 2135
Joined: Tue Oct 05, 2010 5:48 pm

Re: KryoFlux software (DTC, GUI) release history

Post by mr.vince »

First version with ADF writing. Note this is not some shoddy bit shifting, but a complete write emulation of how an Amiga would write the data. You can even simulate the differences between a PAL and an NTSC machine.

We need to tweak and tune it here and there. And yes, not many drives write good and reliable DD stream. The drive you bought with your card was never meant for writing, it was meant for archival, which it does pretty well.

TeaRex
Posts: 120
Joined: Tue Nov 30, 2010 5:36 am

Re: ADF writing experience

Post by TeaRex »

Thanks for your answer. I understand that DD was not exactly the manufacturers' top priority after the early 1990s or so...

Do you have a recommended drive make/model for writing DD disks?

User avatar
mr.vince
Posts: 2135
Joined: Tue Oct 05, 2010 5:48 pm

ADF writing experience

Post by mr.vince »

Not yet, I think much can be adjusted in software by making pre-compensation more aggressive.

I happen to have a dirty-cheap NEC drive that only goes up to track 81, but writes well.

TeaRex
Posts: 120
Joined: Tue Nov 30, 2010 5:36 am

Re: ADF writing experience

Post by TeaRex »

mr.vince wrote:Not yet, I think much can be adjusted in software by making pre-compensation more aggressive.
Does that mean that my experience that a longer cable helps is not an illusion?
EDIT: Maybe a question that's too hard if you aren't an electrical engineer or something like that...
I happen to have a dirty-cheap NEC drive that only goes up to track 81, but writes well.
Thanks, will look for one.

User avatar
mr.vince
Posts: 2135
Joined: Tue Oct 05, 2010 5:48 pm

Re: ADF writing experience

Post by mr.vince »

Longer cables usually dampen signals. I don't see how writing could benefit from this, except for a completely wrong signal level. Usually a longer cable brings more noise, but maybe the longer cable is of a better quality than the short one... Or the short one has a problem with shield...

TeaRex
Posts: 120
Joined: Tue Nov 30, 2010 5:36 am

Re: ADF writing experience

Post by TeaRex »

I want to confirm that using a NEC drive seems to be the solution. All the problems I described are gone with this 1998 drive model NEC FD1231H. As you said, it doesn't go beyond track 81, but I doubt any sane software would use anything above that anyway.

User avatar
mr.vince
Posts: 2135
Joined: Tue Oct 05, 2010 5:48 pm

ADF writing experience

Post by mr.vince »

Super Stardust does that. But that's not sane... ;)

Post Reply