>What about a BA11-V? That's a 4 (dual-height) Q-bus slot box. I'm sure
>the backplane can be made into a Q22 one if it isn't already. Then fill
>it with a CPU card, memory, serial ports and (say) a SCSI card.... Or
>even use it with a TU58 (it's the same physical size as the TU58, and the
>units are designed to stack).
The only problem with that plan is that with a CPU card (say, a KDJ11-A),
memory and serial lines courtesy of an MXV11-B, and some sort of disk
controller like an RQDX3 and the power draw crowbars the power supply.
At least it has done so on every BA11-VA that I've tried...
The only configuration I was able to get to work was two BA11-VAs, with
the Qbus jumper, CPU and MXV11-B in the first box and the RQDX3 and
DELQA in the second box... And that didn't reliably power-up
>At least one DEC book claims that a PDP11 has to have either a Unibus or
>Qbus expansion bus, and that the PRO3xx and PDT11s are not PDP11s because
>of this (for all they run the same instruction srt).
Well, they certainly aren't *typical* pdp-11s with a boot console that
can be programmed like any other, or interrupts which work like other
ones, and the console takes lots of code to emulate a VT100, that's for
sure...
they also have a *64*Hz clock... In RT-11, the clock interrupt service
drops one clock tick out of every 16 -- so it only processes 60 clock
ticks a second... :-)
Megan Gentry
Former RT-11 Developer
+--------------------------------+-------------------------------------+
| Megan Gentry, EMT/B, PP-ASEL | Internet (work): gentry!zk3.dec.com |
| Unix Support Engineering Group | (home): mbg!world.std.com |
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Received on Fri Sep 24 1999 - 18:15:43 BST