Original 11/74 front panel

"Julian Wolfe (FireflyST)" <fireflyst at earthlink.net> wrote: More differences: Don's panel have the location for the key moved to the other side of the parity lamps. Which is rather weird. Also, the screenprint of 11/74 looks shadowed, which is weird. And the right hand side have a different color than the left hand side. And of course, the 11/74s from Tim don't have any CIS stuff on the front panel. (I'm still thinking that Don's panel have never had a matching piece of real hardware, since I don't think that CPU was ever built.) Tim's picture however are of a real machine. Don't know which one, though. If it's just a two CPU machine, it might have been POLLUX::, since CASTOR:: was four CPUs. However, other machine have existed in the past. Yes there were. And the benifits were none. Actually, they were slightly worse than normal 11/70s, but the difference were minimal. After DEC decided to not make the 11/74 into a commercial product, they used 11/74 parts for 11/70 machines. Atleast inhouse. Not sure if any of those parts found their way into customers machines. Used as such, the differences were basically related to cache: The MMU have the cache bypass bit. The ASRB instruction always bypass the cache, and you can also order the machine to explicitly bypass the cache (unless my memory fails me). But nothing of this was used by any OS normally, so the only thing noticeable would be the slower ASRB instruction. Johnny -- Johnny Billquist || "I'm on a bus || on a psychedelic trip email: bqt at update.uu.se || Reading murder books pdp is alive! || tryin' to stay hip" - B. Idol