DEC PDP-11/34A #3

This PDP-11/34A was donated by Thomas Holmes on 12/19/23.

The PDP-11/34 has the KD11-E processor and was introduced in 1976. The 11/34A has the KD11-EA processor, supports the Floating Point and Cache Memory options, and was introduced in 1978.

The KD11-E processor is implemented in a two boards set using M7265 and M7266 processor modules in a DD11-PK backplane. The PDP-11/34 needs a separate M8264 SAC Timeout module. The PDP-11/34A is implemented in a two boards set using M8265 and M8266 processor modules has the SAC Timeout circuitry on the processor modules. Both processors include Memory Management that allows them to access 256 Kbytes of memory.

The PDP-11/34A supports the KK11-A Cache Memory option on a single M8268 module. The KD11-EA Data Paths module must be connected to the  KK11-A Cache Memory module with an over-the-top 40-pin PCB. THis system does not have the KK11-A Cache Memory module.

The PDP-11/34A support a FP11-A Floating Point processor on a single M8267 module. The KD11-EA Data Paths module must be connected to the FP11-A Floating Point module with an over-the-top 40-pin PCB. This system has the FP11-A Floating Point module and a H8822 3-slot over-the-top 40-pin PCB.

Three chassis are available, a 5.25" high BA11-L with a H-777 power supply, the larger 10.5" BA11-K with the H765 power supply, or the huge 21" BA11-F chassis. This system has the BA11-K chassis.

 There are two possible Consoles, the simple Operator's Console, and the more capable Programmer's Console. This system has the Programmer's Console. The M9301 Bootstrap/Terminator module contains test programs, a variety of bootstraps, and a Console Emulator.  The console emulator allows the operator to perform most of the functions of the Programmer's Console using a serial terminal.

There are lots of Unibus peripheral controller options available that can be installed in DD11-CK 4-slot backplanes, or in DD11-DK 9-slot backplanes.

This system has 18-bit parity memory, but does not have the M7850 Parity Controller installed, so the memory will be just 16-bits.

The following boards are installed in the chassis.

Slot P/N Description

1.  ABCDEF M8266 KD11-EA Control

2. ABCDEF M8265 KD11-EA Data Paths

3. ABCDEF M8267 FP11-A Floating Point

4.  

   • AB M9301 Unibus Terminator and Bootstrap

   • CDEF M7859 KY11-LB Console Interface

5. ABCDEF M7891-DH MS11-LD 256 Kbyte 18-bit MOS Memory

6.  

   • AB MUD Slot

   • CDEF M7856 DL11-W Serial Port and Real Time Clock

7.   

   • AB MUD Slot

   • CDEF SPC Slot

8.  

   • AB MUD Slot

   • CDEF SPC Slot

9.  

   • AB M9202 Unibus Jumper

   • CDEF SPC Slot

10. Casting Space for Backplanes

11.  

    • AB M9202 Unibus Jumper

    • CDEF SPC Slot

12.  ABCDEF M7762 RL11 RL02 Disk Controller

13.  

14.  

    • CD G7273 Bus Grant and NPG Jumper

15.  

16.   

    • CDEF M7856 DL11-W Serial Port and Real Time Clock

17.  

18.   

    • CDEF M7856 DL11-W Serial Port and Real Time Clock

19.  

    • AB M9302 Unibus Terminator

    • CDEF SPC Slot