DMA channels and Zorro slots

[HammerD]

Michael Boemer of E3B made a prototype firmware for Prometheus to add Zorro III DMA but I don't think it was ever released.

Actually it didn't add Zorro III DMA but working DMA capability between the PCI slots only.  Of course drivers would have to be adapted to take advantage of that.

[HammerD]

1 DMA Zorro III device with Buster 11 only is what I remember.
Can an expert confirm?
 
Deneb USB card about the only thing out there that uses this ZIII DMA feature. Right?

Yes and a couple others.

Deneb, FastLane Z3, and the C= 4091 scsi card are all Zorro III DMA capable.  Maybe there are some others but I don't think so.

Rev 9 buster can theoretically handle more than one Zorro III DMA device, but there is a bug that happens if Zorro III memory is present.  Revision 11 buster has another bug which limits it to a single Zorro III DMA device. (Don't you just love C= bugs? :-/

The latest Deneb firmware (V11) works around these bugs, so with a Rev 9 buster you could theoretically have two Zorro III DMA devices.

I personally haven't tried it though as the only Zorro III DMA device I have is a Deneb.