Ethan Dicks <ethan.dicks at gmail.com> wrote: Yikes! No, I would not expect it to work well at all. The first, and most obvious problem is the bus. The Unibus is an 18-bit address bus, while the q-bus is 22-bits. So, an 11/70 have a Unibus map which is involved in all DMA from the Unibus. The q-bus don't have anything like that. This obviously affects all device drivers doing DMA. And then we have the obvious problem that the most likely disks used on V7 would have been massbus disks, which you have no correspondance to on a q-bus. But even with disks of a similar nature, such an RL, there are still differences between the controllers, so that you can't just run the version from a unibus on a q-bus machine without a little modification. I don't know how much features V7 uses, but there are plenty of things in the 11/70 which the KDJ11 don't do. Stack limits are different. The MMU is different (although I don't think anyone uses the 11/70-specific features). Now V7 is old enough to not make much use of the hardware, which still makes it easier to get it running on different machines (no split I/D space, no supervisor mode stuff). So, as always, it is possible, but you can't just drop the software in, and expect it to run. True. You need to rewrite things. There is no way you can get something written for the Unibus, and large memory, work on a q-bus without rewriting some stuff. Johnny -- Johnny Billquist || "I'm on a bus || on a psychedelic trip email: bqt at softjar.se || Reading murder books pdp is alive! || tryin' to stay hip" - B. Idol