didn't try devicenet but have used profibus on two machines about two years ago...
just bought the profibus card (was outrageously expensive, i think some $5k or so), plugged it in, wired, set the node address and called it slave. on the plc side (Q02H from Mitsubishi) did pretty much the same, had to use proper GSD file (Fanuc was the only slave with fixed i/o ranges so no setup there). on the robot side, mapped some UOPs and I/O to the cards memory block. there was one issue, card's built in diagnostic would set alarm for lost connection if robot was master but it would not work if robot was slave.