UNIX on PDP-11s

[Johnny Billquist]

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