DEC PDP-11/44 #2
S/N NI02328
This PDP-11/44 was donated by Thomas Holmes on 12/19/23.
The PDP-11/44 was introduced in 1979 as a replacement for the PDP-11/45 and PDP-11/70 systems. It has Memory Management with a 22-bit address and can support 4 Megabytes of RAM. It was the last PDP-11 to be built without a microprocessor based CPU.
The base PDP-11/44 consisted of a BA11-AA 10.5" chassis with a DD11-DK backplane and an H7144-AA power supply. The power supply can make up to 120A of 5.0V, and +/-15V.The chassis was typically mounted in a short M9642 cabinet with a 872-D Power Controller. For diagnostics the PDP-11/44 could boot from an optional TU58 Cartridge Tape Drive. This system has 3x 256k Byte memory boards, but 512k Byte and 758k Byte memory boards were available. The Multifunction Module in the processor contains an onboard 8085 processor to implement the console command set and diagnostics, and has two serial ports. One port is for the serial console terminal, and the second is for the TU58 Cartridge Tape Drive.
The following boards are installed in the chassis.
Slot P/N Description
AB M7090 KD11-Z Console Interface Module
CDEF Reserved for KE44-A CIS Control Store
ABCDEF Reserved for KE44-A CIS Data Path/Logic
ABCDEF M7093 KD11-Z FP11-F Floating Point Processor
ABCDEF M7094 KD11-Z Data Path Module
ABCDEF M7095 KD11-Z Control Module
ABCDEF M7096 KD11-Z Multifunction Module
ABCDEF M7097 KD11-Z KK11-B 4k-Word Cache
ABCDEF M7098 KD11-Z Unibus Interface
ABCDEF M8722-BC MS11-MB 256k Bytes MOS Memory with ECC
ABCDEF M8722-BB MS11-MB 256k Bytes MOS Memory with ECC
ABCDEF M8722-BB MS11-MB 256k Bytes MOS Memory with ECC
ABCDEF Reserved for Memory
ABCDEF M7762 RL11 RL02 Disk Controller
AB UNIBUS Jumper
CD G7273 Bus Grant and NPG Jumper
EF
Casting Space for Backplanes
AB UNIBUS Jumper
CD G7273 Bus Grant and NPG Jumper
ABCDEF M7819 DZ-11 8x Serial Ports
AB
CDEF M7856 DL11-W Serial Port and RTC
ABCDEF M8716 DR11-W DMA Interface
AB
CD G7273 Bus Grant and NPG Jumper
EF
ABCDEF M7892 ????
AB
CDEF MDB-LP11 Printer Controller
AB M9302 Missing UNIBUS Terminator
CD G7273 Bus Grant and NPG Jumper
EF
