On 2013-01-03 18:37, John Wilson wrote: Trivia question: what are the major differences between programming the DU11 and the DUV11? At least from the handbook descriptions, it sounds like the DUV11's isochronous (= async?) mode works and the DU11's doesn't, but that's the only difference I can see and I don't see how it matters for DDCMP use. And yet, DECnet/RSX has different names for them, as if it's using separate drivers for each. If DECnet/RSX uses different names, then it is also definitely using different drivers. However, who knows if the actual contents of the drivers differ, or if they just liked having different names for them. :-) (I can check next week. Please remind me...) Johnny