Tu10 pdp11

william degnan billdegnan at gmail.com
Sun Sep 6 07:21:33 CDT 2015

I am going to see if I can find the card inventory and installtion guide
info for the TM11  so that I can confirm whether I indeed have one
installed in the TU10'S cabinet.  So far I have found little.

Bill Degnan
twitter: billdeg
On Sep 6, 2015 8:14 AM, "Johnny Billquist" <bqt at update.uu.se> wrote:

> On 2015-09-05 20:25, Noel Chiappa wrote:
>>      > From william degnan
>>      > I was looking to see if references to the tm11 were "module/card"
>> or
>>      > backplane interface.
>> I think pretty much all that earliest generation of UNIBUS interfaces were
>> stand-alone backplanes (i.e. 19" wide things that went in an H960 in a
>> fixed
>> location, and were filled with the small Flip Chip modules); the RK11-C,
>> RP11-C, RF11, and TC11 all are.
> Partly correct. All early Unibus controllers which did DMA had their own
> backplanes. Which is why the NPR is obnoxious on the Unibus. Unlike the BR
> lines, the NPR is normally always just jumpered in the backplane, and
> located away from the BR lines. When DMA on single cards became more
> common, this became an obvious issue on the Unibus. You have to cut the
> wire on the backplane, and when you remove the card you either have to
> reinsert the write, or get the bug grant card that is double height, which
> also do the NPR jumper.
> But non-DMA controllers were single cards even back in the early days of
> the Unibus, like the DL-11.
> (Early DMA controllers were all multiple cards, so having their own
> dedicated backplanes were a pretty sane idea.)
>         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

More information about the cctech mailing list