Pci-fdc

[Nick_Zravre]

I'm looking for a PCI floppy disk drive controller; it must be for the PCI bus.
It also must be capable of supporting 2-8 floppy disk drives, otherwise it is nearly useless to me.

[Chuck(G)]

I'm not aware that there has ever been a legacy controller made for the PCI bus. The only PCI-bus floppy controller that I'm aware of is the Catweasel (MK3 or MK4). But it's a very different animal from a traditional controller.

There's no reason it couldn't be made to support two eight-inch drives exernally, though it might take some doing.

[Sharkonwheels]

I'm looking for a PCI floppy disk drive controller; it must be for the PCI bus.
It also must be capable of supporting 2-8 floppy disk drives, otherwise it is nearly useless to me.

Dude, if that existed, we'd all have them.
Why ya think we all have to keep ISA-based systems running for imaging?

Beside that, the PC never used 8" FDD's, so that is a mission in itself.

What *I* use for 8" is:

CompatiCard IV
Acer Pentium 75 w/ 64M RAM, 2GB IDE (CompatiCard requires P75 or SLOWER)
dbit.com FDADAP for connecting 8" drives to the CompatiCard IV
Various drives: Shugart 801 and 851 8" drives, 3.5" 720kb and 1.44MB, 5.25" 360KB, 720KB, and 1.2MB FDD's.

You MIGHT be able to get away with something like an ISA-bus based system, using the FDC on an Adaptec AHA1542B SCSI controller, and the FDADAP to connect the 8" drive, and using TeleDisk/IMD/etc...
Note that it MUST be a 'B' model, as I have never gotten a 'C' model to work properly. The 1542B will read single-density, and I have tried it and verified it.

By the time PCI was out, pretty much most, if not all mainboards, had most I/O onboard, from FDC to IDE, Serial, Parallel, PS/2, etc...

I, myself, have never seen a "true" PCI Floppy controller.
A Catweasel is an add-on that is driven by special software, ie, I don't think DOS/Windows sees the CatWeasel as an FDD and will use it accordingly.


T

[Arkhan]

I think he wants it to support up to 8 drives, not 8" floppy disk drives!

[Chuck(G)]

I think he wants it to support up to 8 drives, not 8" floppy disk drives!

It does read that way, but it didn't make any sense...

[Chuck(G)]

Beside that, the PC never used 8" FDD's, so that is a mission in itself.

For that, you'd have to go to the DisplayWriter. But the 5150 hadn't been out for very long (a few months) before there were 8" kits offered for it.


Acer Pentium 75 w/ 64M RAM, 2GB IDE (CompatiCard requires P75 or SLOWER)

Nonsense--on the table to my right, I've got a 366 MHz Celeron system running with a CC IV. Works fine. If you find your system CPU- and not bus- speed limited, it's just a sign that someone doesn't know how to code delay loops.

There were lots of SCSI-mit-Floppy 8- and 16-bit controllers. I like the DTC and Ultrastors because they used the National 8473 FDC, which can do some tricks that the 8477 and Intel 82077 can't.

But that's another story... :)

I found that a Catweasel MK 3 couldn't quite handle two Siemens FDD-200s at the end of a 6 ft. cable. I made a small board that buffers the CW outputs using 7438s to provide a little more drive. YMMV.

[Sharkonwheels]

Nonsense--on the table to my right, I've got a 366 MHz Celeron system running with a CC IV.YMMV.

Apparently, mileage DOES vary, because according to MicroSolutions themselves, and I have verified on a few of MY machine, the onboard BIOS does NOT work reliably, if at all, on machines with CPU's above 75mHz:

This self extracting file contains software BIOS version 1.06. If you have a CompatiCard IV in a P90+ machine you will need to use the NOROM option and this software BIOS. See page 4-18 in your users guide for more information about the NOROM option.

You can check in THIS (http://vt100.net/mirror/harte/MicroSolutions/Compaticard_IV.zip) archive, and see for yourself what MicroSolutions says in the file named "compaticard_index.txt"

If I use a proc above 75, I need to disable the onboard BIOS, which I find inconvenient, and ya gotta keep futzing around with the config.sys file every tie ya screw around with the drive config, for it to work 100%.

T

[Sharkonwheels]

I think he wants it to support up to 8 drives, not 8" floppy disk drives!

OK - but does it REALLY change the answer?
Anyone ever SEEN a PCI FDC?

I think the answer pretty much remains the same - the CompatiCard will allow 4 FDD's, only issue is will the mainboard FDC allow 4. Without some sort of driver, a BIOS only reognizes (2) FDD's, correct? meaning (2) on the mainboard, + (4) using a CCIV + CCDRIVE.SYS = 6 drives.

Maybe (2) CCIV's in one machine?
Big@ss investment, though - hard to find a CCIV for less than $150 nowadays - I wouldn't let mine go for triple that :)

T

[Nick_Zravre]

I really just need a pci floppy disk drive controller, that can support 2 disk drives, somewhere between 4 to 8 would be better though. If they don't exist I might try my hand at making a few, who knows it might be a lucrative business.

[Terry Yager]

Anyone ever SEEN a PCI FDC?

T

I think I have, but I may have been hallucinating...

--T

[Sharkonwheels]

I've never seen one, personally.
Even when the PCI Adaptec controllers came out, they no longer had on FDC onboard.
I think the AHA-2942 might've been their first standard PCI SCSI, and had no FDC, unlike the 1542's (ISA), 1742's (EISA), etc...

T

[Nick_Zravre]

Unfortunately, I can't use isa to pci/pci to isa bridges due to the lack of direct memory access.

[MikeS]

They did exist; e.g.:
http://stason.org/TULARC/pc/hard-disk-floppy-controllers/E-H/GIGA-BYTE-TECHNOLOGY-CO-LTD-Four-IDE-AT-drives-GA.html

I have to ask: Why do you need *8* floppies?

m

[Nick_Zravre]

I have two 3 1/2" drives two 5 1/4" drives 2 8" drives (which I have already found adapters for). I would be able to make do with just 1 of the 3.5 and 5.25 inch drives, thereby limiting it to 4 in all. I'll probably just try and make one that works by examining schematics and pinouts of controller chips, if I come up with something that works I might try and make a profit.

[barythrin]

Perhaps I'm incorrect since I somewhat recall floppy drive support on paper being up to 4 devices but I've never seen anything documented in int 13 regarding addresses past 01 for floppies.. and most BIOSes only support 2 of course. Not sure.

[Sharkonwheels]

Perhaps I'm incorrect since I somewhat recall floppy drive support on paper being up to 4 devices but I've never seen anything documented in int 13 regarding addresses past 01 for floppies.. and most BIOSes only support 2 of course. Not sure.

The CompatiCard IV is a special case, though, as it uses a device driver (CCDRIVE.SYS I think) to go beyond the standard 2 drives, which is why I suggested it, if a PCI card could not be found.

With the CCIV, I can get up to 6: (2) on the mainboard/Adaptec card, plus (4) more on the CCIV card.


T

[carlsson]

Perhaps you can cluster together several PCs instead of building one monster PC with all eight drives? :-D In terms of complexity, I almost think it will be easier to network four regular PCs in a cluster where you use some custom drive numbering than make your own floppy drive interface and software to support it.

[MikeS]

Perhaps you can cluster together several PCs instead of building one monster PC with all eight drives? :-D In terms of complexity, I almost think it will be easier to network four regular PCs in a cluster where you use some custom drive numbering than make your own floppy drive interface and software to support it.
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Or have at least one slower ISA-slot machine networked to the main machine; ISA controllers to let you have >2 floppies are much easier to find...

m

[Sharkonwheels]

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Or have at least one slower ISA-slot machine networked to the main machine; ISA controllers to let you have >2 floppies are much easier to find...

m

They can even still be found brand-new, to boot!

T

[Chuck(G)]

They did exist; e.g.:
http://stason.org/TULARC/pc/hard-disk-floppy-controllers/E-H/GIGA-BYTE-TECHNOLOGY-CO-LTD-Four-IDE-AT-drives-GA.html

I have to ask: Why do you need *8* floppies?


Interesting. From the user's manual for the GA107 and 108, they were indeed PCI using the UMC "multi-I/O" chip that many manufacturers simply plopped onto the motherboard. Unfortunately, they also use the CMD640 IDE controller chip which is the pits.

You can put up to 4 Compaticard IVs in a machine if you disable the primary FDC, giving you access to 16 drives. BIOS support is provided after a fashion (you'd best load the BIOS as a TSR, and not use the onboard PROM. What's more, if you intend to use only one drive at a time, you can share IRQ 6, DMA 2 among the 4.

The problem is that not every product knows about secondary controllers or even BIOS IDs other than 0 and 1. This leads to the "you can't get to that drive from here" type problems.

We put out a product called Sydupe that pushed the limits of what could be done with CC IVs. We ran 3 parallel channels of transfer, copying 3 disks at once. You needed to use different IRQ, DMA and port addresses for each CC, but it worked.

At least with 360 and 720K diskettes, that is. There's just not enough bandwidth in the DMA path to support 3 1.44 or 1.2MB copies. Two at once is the best you can do there.

I use a pretty broad selection of drive types, including 3.0" and 3.25" and Drivetek. But I gave up the idea of putting them all on the same box. Instead, I've got each drive in its own external drive case with a DC-37 plug at the end of a cable. I can select among not only drive types, but which of three different controller types (CW, PC Legacy, WD17xx) to plug them into. It works very well.

[Nick_Zravre]

I had thought of the networking of drives together, however, my only other computer that is networked needs the capacitors on the mainboard replaced; it is a IBM 300PL 6862. It will be more educational to make a pci fdc that supports 3.5", 5.25", and 8" disk drives; I already found a controller chip that would work well.

[MikeS]

I had thought of the networking of drives together, however, my only other computer that is networked needs the capacitors on the mainboard replaced; it is a IBM 300PL 6862. It will be more educational to make a pci fdc that supports 3.5", 5.25", and 8" disk drives; I already found a controller chip that would work well.
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Good luck; sounds like a worthwhile project.

Are you sure that 6862 is not a 300GL? I have a bunch of those that are headed for the scrap pile, in case you want a MoBo.

[Nick_Zravre]

Yeah, I'm sure that it is a 300PL. I'll eventually just replace the capacitors, when I am more sure of my soldering skill and have had some more practice.

[MikeS]

Well, well, learn something every day. The 6862 beside me here is a 300GL, but there were indeed PLs and GLs with the same model, only different suffixes; that suggests that the MoBo is the same, but probably with a different CPU. Interesting.

Definitely not a good box for multiple FDDs though... ;-)

Let us know how you get on with that controller project; sounds useful.

m

[Druid6900]

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Good luck; sounds like a worthwhile project.

Are you sure that 6862 is not a 300GL? I have a bunch of those that are headed for the scrap pile, in case you want a MoBo.

Who are you calling a scrap pile?

[Terry Yager]

Scrappy, ain't we?

--T

[MikeS]

Who are you calling a scrap pile?
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I was just anticipating what you are going to do with them, considering your enthusiasm for this particular model.

[Druid6900]

It's not a matter of enthusiasm, more of over-abundance :)