PDP11 adventures

Adrian Graham witchy at binarydinosaurs.co.uk
Tue Dec 5 14:08:00 CST 2006

> On Mon, 2006-12-04 at 15:20 -0500, Curtis H. Wilbar Jr. wrote:
>> OK... so I'm now the new (proud :-) ) owner of a PDP-11/83.

Congrats! I've been battling with a reluctant 11/73 today in the workshop,
on work's time :) We have some RD53s to test for a customer.....

>> There doesn't seem to be a reason to the layout of the grant continuity
>> cards.
>> Shouldn't there be one in the left side of the 3rd slot from the top in
>> the 183QA-D2
>> (system unit) ?

No, the first 3 slots of the Q22 bus carry the grant continuity on the CD
portion so a dual-height card in the AB side of slot 3 is fine.
>> Any pointers on how the RQDX3 and RQDXE cards should wire up ?  The
>> RQDXE in the system unit has a wide ribbon cable running to the front
>> (which I presume breaks into the control/data wiring for an MFM drive
>> there).. but the RQDX3 doesn't connect to the RQDXE ..

I've just done this today - the RQDXE goes in the last AB slot with the BA23
drive bay cable going to the back-most connector, the external port
(multi-coloured cable) goes in the middle connector and the cable to the
RQDX3 goes to the front-most connector, ie nearest the backplane fingers.
There are jumpers to select too, and the manual for those is available on
MANX and Bitsavers.....many thanks to the folks involved there.

Binary Dinosaurs creator/curator
Www.binarydinosaurs.co.uk - the UK's biggest private home computer

More information about the cctech mailing list