UNIX on PDP-11s - test-drb@ccmp.vtda.org

11 Jun 2009

ard at p850ug1.demon.co.uk (Tony Duell) wrote:

...
       Hmm, MSCP on
my PDP-11/24. 8-) 
 Yes, with a high-speed RD52 for authenticity ;-)  Not
possible. The only MSCP controller DEC did for Unibus was to SDI 
 (tha UDA50). The only MSCP to MFM controller DEC did was for Q-bus (the 
 RQDX series).  
 What happens if you put a DW11B (Unius - Qbus interface) in the Unibus 
 machine and connect the Qbus side of that to an RQDXm? Obviously it can 
 only support 18 it DMA, but it does support that.

 I know for a fact that you can use an RLV11 on a Unibus machine that way, 
 I did it on an 11/45 with no problems. 
Yeah, that could possibly work. As long as you accept the 18-bit DMA 
address limitation.
I think the UDA50 and the KDA50/RQDX all look similar enough at the port 
level that it could work fine.

	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