@mboehmer_e3b
I used google translate on some of your comments on a1k.org:
DMA on Zorro III is dependent on the remaining machine configuration and is not at all guaranteed configurations (depending on the specific Buster revision and other existing DMA devices).
Can you examplify setups that will cause DMA not to work ?
PIV, CVPPC, Buster11, A2065, Prelude = Will any of these cause DMA not to work?