ElectroSoldier wrote on 2023-09-28, 02:13:

I have an adaptec SCSI card that has a floppy controller on it but that is an ISA bus card. I was wondering if there is something similar for the PCI bus?

Normal FDC uses ISA DMA - pretty much impossible on PCI.

Or maybe a 5.25" SCSI floppy drive?

Software support was poor even back in the era - Teac FD235-HS SCSI floppy

There's a buslogic PCI SCSI card that lists floppy support... but I don't see a 34 pin interface on it. Therefore I wonder if it has special onboard BIOS extension for handling SCSI floppies... or not and a mistake in tech specs has just been copy pasted for decades.

BitWrangler wrote on 2023-09-28, 15:16:

There's a buslogic PCI SCSI card that lists floppy support... but I don't see a 34 pin interface on it. Therefore I wonder if it has special onboard BIOS extension for handling SCSI floppies... or not and a mistake in tech specs has just been copy pasted for decades.

Perhaps it means SCSI floppy drives.
I noted it earlier during Windows NT setup driver loading.
But I have never seen one.

Grzyb wrote on 2023-09-28, 07:12:

Normal FDC uses ISA DMA

its wired to ISA DMA controller, but its not mandatory https://wiki.osdev.org/Floppy_Disk_Controller … _Data_Transfers
I seem to remember a HP Omnibook without one and working floppy https://www.cs.hmc.edu/~fleck/iowa-lab/omnibook.html It even runs win95 and apparently floppy works there. Some funny quirks tho: https://www.elhvb.com/mobokive/edwin/laptops/ … ce/OB600_fg.pdf

Undelete in File Manager causes GPF or Divide by Zero Overflow- due to no DMA
Use the extended DOS tools.

No DMA wont be a problem for software going thru bios interrupt routines.

BT-956CD and variants is the BusLogic card I mentioned.

edit: Hmmm manual is on archive.org https://archive.org/details/manualzilla-id-68 … ge/n33/mode/2up and at a quick scan all I see about floppies is it needs a normal floppy drive for driver install, and that it supports a config switch for removable media so the OS doesn't freak out when you change disks.

Another idea occured. Floppy Tape drive manufacturers started making alternate address floppy tech controllers for their tape drives so they could be used independently of floppy controller, and maybe they got a feature or two extra... the ones I have seen have been ISA... I'm just wondering if floppy tape drives lasted long enough that they made a PCI version... it would however need a lot of messing around to access a floppy drive plugged into one and best you might hope for is a dump of contents or image rather than an an online filesystem.

I dont know if someone already mention, but with USB 3.5 floppy i have very good support using omniflop as driver

http://www.shlock.co.uk/Utils/OmniFlop/OmniFlop.htm

I read very weird formats without problem

I use this cheap addaptor from ebay

theelf wrote on 2023-09-28, 16:36:

I dont know if someone already mention, but with USB 3.5 floppy i have very good support using omniflop as driver […]
Show full quote

I dont know if someone already mention, but with USB 3.5 floppy i have very good support using omniflop as driver

http://www.shlock.co.uk/Utils/OmniFlop/OmniFlop.htm

I read very weird formats without problem

I use this cheap addaptor from ebay

I wonder if you replace the header with male pins, if you could use a 5.25" floppy drive with one of these. I'm ordering one to tinker with.

vileboss wrote on 2026-01-05, 19:14:

I wonder if you replace the header with male pins, if you could use a 5.25" floppy drive with one of these. I'm ordering one to tinker with.

What I saw from other posts on the internet this will not work with 5.25" floppy drives.

Yoghoo wrote on 2026-01-05, 19:36:

vileboss wrote on 2026-01-05, 19:14:

I wonder if you replace the header with male pins, if you could use a 5.25" floppy drive with one of these. I'm ordering one to tinker with.

What I saw from other posts on the internet this will not work with 5.25" floppy drives.

I seen similar posts when I first found the adapter for sale, however I'm thinking this is only stated because the female 34 pin header on the board is physically incompatible with the drives - since most (if not all of the PC drives) use a card edge connector, and all floppy cables that have 34pin connectors are female as well.

vileboss wrote on 2026-01-05, 19:14:

theelf wrote on 2023-09-28, 16:36:

I dont know if someone already mention, but with USB 3.5 floppy i have very good support using omniflop as driver […]
Show full quote

I dont know if someone already mention, but with USB 3.5 floppy i have very good support using omniflop as driver

http://www.shlock.co.uk/Utils/OmniFlop/OmniFlop.htm

I read very weird formats without problem

I use this cheap addaptor from ebay

I wonder if you replace the header with male pins, if you could use a 5.25" floppy drive with one of these. I'm ordering one to tinker with.

Long time ago, i made a small personal project to do this, with some success, but with a NEC usb floppy UF001 version

https://forum.vcfed.org/index.php?threads/rev … y-idea.1248653/

ElectroSoldier wrote on 2023-09-28, 02:13:

... I just want to be able to download files on a modern PC write those files to a floppy disk when needed so I can move them over to a retro PC when needed...

Moving files between "modern" system with no floppy and "retro" DOS system can be tricky.

If you are trying to make/move a bootable floppy image, you may want to ZIP it into a smaller movable file, and create the actual floppy on the DOS system.

If your retro system is new enough, it's BIOS may recognize a USB flash drive... You would have to format it there, but modern systems can often access older file systems (don't let it "scan and fix").

A GoTek floppy emulator will let the retro system access "floppies" stored on a USB stick - I find that image#00 (first one) can be accessed directly in my Win7 system without any additional hardware or software.

Otherwise the nost "compatible" interfaces are Netowrk and Serial.

--

For serial, you can use any TTY program that supports things like Xmodem, Ymodem or Zmodem file transfer. You can also use my DDLINK (see later)

Many of the old programs needed to perform such transfers run under DOS - not a prob. on the DOS system, and DosBox makes then runnable on most modern systems.

--

Network is much faster, but harder to set up... You will need a network interface on the DOS systems. If lucky your mainboard may have one built in, otherwise I keep a box od older ISA and PCI NICs, most of them NE2000 compatibles.

The networking components from WFW can be extracted and run independently under DOS - keep in mind that these older not-secure protocols have be disabled in modern Winblows - but can be enabled.

You can also use Brutmans MTCP to be able to perform FTP transfers.

Both of these will require some install/setup and have to co-exist with other "nodes" on your network.

I perfer my own DDLINK - it doesn't have to be installed or configured on needs only a "crynwar" packet-driver to access the network. It's been discussed in a couple other forums, search "DDLINK" to see more about it.

--

The hardest retro DOS PC I have is a "PoQet PC" - a tiny 8088 laptop with no floppy and CMOS battery-backed-up RAMdrive for main storage. The internal lithum battery is long-dead and I don't use it enough to keep one fresh.

I also don't have the various interface cables to connect to it's proprietary expansion connector - I was able to find it's pinout and make a serial cable.

To test/run stuff on it, I need to use DDLINK which can /Bootstrap itself to a new system over serial ... then I use it to move what I want to the freshly formatted "hard" RAMdrive.

--

The other common interface on retro PCs is parallel - I've not found a good way to move files over LPT with a modern PC, but DDLINK can do it (on a DOS pc, DosBox doesn't support LPT hardware enough to work)...

But parallel transfers are MUCH faster than serial - so sometimes I use another (more connected) retro PC to get larger files on/off less connected ones.

Not sure if it could help,but I found this: https://github.com/dhansel/ArduinoFDC
"ArduinoFDC works with double density (DD) as well as high density (HD) disk drives. It can read, write and format 5.25" DD (360KB), 5.25" HD (1.2MB), 3.5" DD (720KB) and 3.5" HD (1.44MB) disks."

nali wrote on 2026-01-10, 01:15:

Not sure if it could help,but I found this: ...

Interesting little device. Looks like it's interface is serial, so likely a USB RS-232 module on a "modern" system.

It can read/write entire disks, or individual files and transfer via XMODEM at 115200 bits/second. You wull need a good TTY program capable of that in the modern system, expect over 2moins to transfer a 1.4M disk image (plus write time to floppy)

And you are going to have to build it and do some work to manipulate files/disks etc.

I'd still recomment my DDLINK solution, it can work faster and more reliably via serial (1024 byte blocks with full CRC .vs. Xmodem 128 byte blocks with simple checksum).
And nothing to build but a null-modem cable (which you still have to make for the Ardunio solution)

Yes, you would have to use DosBox on the modern side, but that is very handy for running all kinds if DOS tools anyway... I have it on almost all of my "modern" systems, and I find it's serial interface capability quite good.

And it you really want floppies, write them on the retru side using something like my XDISK tool.

This is all assuming you have DOS on the retro system or can get to DOS (ie: Win9x)
worst case you could boot DOS from floppy to do the transfer - I can provide floppy images to enable this (in about a month)

[PS: Sorry for excessuve typo's etc. in my posts of last few weeks ... I'm on a ship and have to do this forum on my phone with fairlt spotty internet]