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by philpem 2632 days ago
Or if you prefer free-as-in-speech kit, there's also Discferret (www.discferret.org) and a ton of other similar community-developed tools :)

(Full disclosure: I'm one of the guys behind Discferret but it hasn't seen much dev work recently due to lack of time on my part)
2 comments
tiben_ 2632 days ago
Seems the correct project URL is : https://discferret.com

That's interesting i was not aware of this project. I'll take a further look asap. Is there some feature/comparison sheet with Kryoflux available ?

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philpem 2632 days ago
Sorry, quite correct. Apparently I can't even remember my own domain name!

It'll do exactly what a Kryoflux can do, including flux-transition-level read and write. (I'm not sure if the Kryoflux can write). The big differences are that it has a complete Shugart drive interface which matches what floppy drive datasheets advise -- so it's fully open-collector, with the right type of gates.

This also makes it very flexible -- it's been used to read ST506 MFM/RLL drives and decode the resulting output. It's been connected to NEC 8-inch drives with non-Shugart interfaces.

Its only major problem was that it was expensive - about $150 per unit. You could probably get that down a lot by using a more appropriate FPGA. If I did it again, I'd probably use a Lattice MachXO and the Yosys/Nextpnr toolkit, and possibly an STM32 microcontroller.

Practically speaking if you didn't need Winchester support, you could probably use the STM32's timer and PWM peripherals with DMA reload, leaving a single-chip solution with a bit of LSTTL for the drive interface.

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pronoiac 2632 days ago
Heads up, store.discferret.com isn't resolving.
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philpem 2625 days ago
The store closed years ago. I was working 7am-6pm for a long while and just didn't have the time to put in.

I still have about a dozen boards and a few components, actually. Look me up on Twitter (@philpem) or Mastodon (m0ofx@mastodon.social) if you're interested in a board, my usual offer is "beer money plus shipping" :)

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tiben_ 2632 days ago
Thank you for theses details. Kryoflux can write back a read raw stream or some common image formats (IFP, ADF, G64 etc.)
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EvanAnderson 2632 days ago
Oh, wow. This is pretty cool. I've got some fairly oddball 5 1/4" disks from the 1980's that I'd like to try to preserve, and this looks like it would do the job. I'll echo what another comment says-- the store URL isn't resolving. I'd love to purchase one of these units.

I thought about using Kryoflux in the past, but their licensing is a complete non-starter for me. I'm not going to purchase hardware and license software that limit what I am allowed to do with it.

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philpem 2625 days ago
Unfortunately I don't sell the ready-made units any more -- they're just not cost-effective to sell like that at a price the market will bear.

I want to do a redesign with more cost-effective components (an STM32 Nucleo and a shield or Morpho backpack is one idea I'm considering).

I do have some PCBs left over, a bill of materials and can give you some guidance with part substitutions if you want to DIY one. Feel free to drop me a note on Twitter (@philpem), Mastodon (https://mastodon.social/@m0ofx) or email (via www.philpem.me.uk) if you're interested.

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