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PCI to ISA adapter boards?

Here's the datasheet for the bridge chip in that thing. Perhaps tellingly it says:

CH365 converts the 32-bit high-speed PCI bus into an easy-to-use 8-bit active parallel interface which is similar to ISA bus, for making low-cost computer board card based on PCI bus, and upgrading the
original board card based on ISA bus onto PCI bus.

And yes, it doesn't support DMA at all. It gives you a limited address bus, memory and I/O read and write signals, and a single interrupt request line. The driver for it (which has to be loaded before your ISA driver) sets up I/O mapping for it to match what you've set up on the plugged in card to the best of its abilities and you're off to the races. Given its limitations I don't see a ton of practical use for it, you're certainly not going to be using it to drive a Soundblaster card or anything fun like that (although, technically, maybe an adlib card would work?), but it would maybe do the job to adapt some kind of simple data collection widget or whatever.
 
What @Makefile said. I've got an industrial P4 board with 3 ISA slots and a PCI-to-ISA bridge chip. DMA doesn't work. I have a P3 with the 820 chipset (RDRAM memory) with a PCI-to-ISA bridge chip. DMA doesn't work. I've got a couple of 440BX/GX P3 boards and DMA works fine.
I think the P4 uses the IT8888G bridge chip, which supposedly provides DMA; but you could fool me--maybe it isn't set up right in the BIOS.
The P3 uses the National PC87200 bridge chip, which supposedly also provides ISA DMA, but I've never got that to work either.
At one time I thought about getting into debugging either one of these systems to get the straight poop on DMA, but never got around to it--just reverted to the 440 chipset P3s.
 
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Amazing that the web page is still around (ca. 2000). Shorter answer--for some limited number of devices where appropriate drivers are available and will work. I am not aware of anyone who has used this lashup successfully.
 
Still, I'm thinking of trying to build this project:

dISAppointment - LPC to ISA adapter - ISA on modern motherboards \ VOGONS

www.vogons.org www.vogons.org

And if it works, then use this adapter:
texelec.com

Quad-Flop - Four Port ISA Floppy Controller - TexElec

The Quad-Flop has finally arrived! What is it? 4-port floppy controller based on the National Semiconductor PC8477B “Advanced Floppy Disk Controller” IC. Atmel ATMEGA4808 microcontroller to monitor & display track position, enable TG43 and control write protection. Removable 3-digit display...
texelec.com texelec.com
 
I've got several P3 and P4 boards with ISA slots that use a PCI-to-ISA bridge chip; almost all use the ITE8888. Floppy controllers don't work at all in my experience-the fly in the ointment seems to be the 8-bit DMA. The FDC is seen, but when it comes to reading or writing using DMA, nothing happens. Even some old K6 boards with ISA onboard don't support secondary floppy controllers.

I wish you success in your efforts, however. :)
 
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At $dayjob, we have some PCs that are used as antenna controllers. The special interface card is ISA; it has three Motorola 68230 Parallel Interface/Timers (PI/T) chips and three Intel 8254 Programmable Interval Timer (PIT) chips, along with a couple A/D converters and assorted other 'stuff' spread across many ports and many port ranges. No DMA or active IRQs, thankfully.

The original systems were DOS based and ran Socket 370 motherboards and worked great. The upgrade, to a WinXP based software system, used IEI ROCKY-6614 industrial PICMIG socket LGA775 Pentium 4 SBCs on passive PCI/ISA backplanes, and that works great. The ROCKY-6614 uses a Winbond W83697HF/HG chip to provide the ISA bus, and all works swimmingly. Unless I remember things incorrectly the board has two, one as a super I/O and one to drive the ISA; I don't have one in front of me to double check.

Unfortunately, those ROCKY-6614 SBCs were made in the middle of the capacitor plague days, and they started failing. New ROCKY-6614 boards are available, but they aren't inexpensive. So I decided to try one of these Intel 945 Core2 Duo motherboards with ISA slots that pop up on eBay from time to time for a couple hundred dollars.

Long story short: the ISA bridge on those Core2 Duo Intel 945 boards only handles a very limited number of ports and port ranges, about half of the amount needed to run the custom ISA card. No fun. Even less fun is sending a return back to China have having to pay import duty on it. Yeah, a return, with import duty, which was about $80 for those boards. Each. Plus shipping of around $80. Poor seller took that one to the chin, unfortunately. I was willing to pay shipping, and did in fact pay the return shipping, but the import duty was another matter.

But the Winbond W83697HF/HG seems solid, at least for this purpose. No clue how good the FDC support in it is, but it does do a full range of ISA ports like a champ.
 
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