Paul Anderson <useddec at gmail.com> wrote:
If the RK11-D in the last thing on the bus, remove the
M930 terminator
and place the BC11-A cable going to TM11 there, and then terminate the
Unibus in the TM11. The RK05 can only be connected to another RK05
(or RK03), or the terminator.
I hope that solves your problems, and good luck, that's a nice system.
Thanks.
I am using it as my test system before I tackle my PDP-11/20
system.
Paul
Yikes! I checked the PDP-11 and the RK05. I am happy to report that both
survived the newbie torture test!! RT11 w/ MUBAS is still operational :-)
I never considered the fact that the bus inside the main system is so tailored
to the cards installed within them, especially on a slot by slot basis.
If I understand things correctly, the first RK05 drive cable is
attached to the bus
opposite the M7255 card. The RK05's are daisy chained together. The last
RK05 has an M930 terminator. In the main cabinet, the M930 terminator
opposite the M7257 card is removed and the BC11 cable leading to the 1st
slot in the TMA-11 is installed. The M930 terminator in the TMA-11 now
becomes the Unibus terminator. If the entire Unibus chain is <50 ft, then we
are good.
Are all BC11 cables the same? I see some with M919 connectors and others
with M929?
Many thanks!
PS. I am still looking for an installable RSTS-11 (version 4 or LESS) so I can
prep an RK05 drive under SimH where I can copy the image onto a real RK05
disk pack (I wrote some software to do this)
--barrym