View source for DD11-P backplane

The '''DD11-P backplane''' is a 9-slot [[Modified UNIBUS Device|MUD]] [[backplane]] [[system unit]], with special modifications so it could be used to hold the [[KD11-E CPU|KD11-E]] or [[KD11-EA CPU]] of the [[PDP-11/34]] or [[PDP-11/34A]] (respectively). The [[Central Processing Unit|CPU]], which consisted of two [[DEC card form factor|hex]] [[printed circuit board|boards]], was installed in slots 1 and 2, which were specially wired to hold them.

It could also be used to hold the single-board [[KD11-D CPU]] of the [[PDP-11/04]]. In this case, slot 2 could hold a MUD [[main memory]] card such as an [[MS11 32KB MOS memory]] or [[MM11-D core memory]].

(The details of the modifications are not yet worked out, but could not have been extensive, in view of the above. Certainly the [[bus grant line]]s would have been wired past slot 2, and there may have been an inter-card [[bus]] of some sort.)

It was normally installed in a [[BA11 mounting boxes|BA11 mounting box]]. There are two versions, the '''DD11-PF''' and '''DD11-PK''', intended for use in the [[BA11-F Mounting Box]] and [[BA11-K mounting box]], respectively; they differ basically only in the length of the [[power harness]], although the two take +5VB (battery backup) on different [[pin]]s of the [[DEC power distribution connectors]].

==External links==

* [http://www.bitsavers.org/pdf/dec/unibus/DD11-P_RevD_Engineering_Drawings_Feb77.pdf DD11-P Engineering Drawings]

[[Category: UNIBUS Backplanes]]