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PCI to ISA adapter boards?

ISA DMA is the Achilles heel of such things as well as industrial boards with ISA slots
 
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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