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Pdp11 44.jpg
PDP-11/44 from a sales brochure.
Manufacturer: Digital Equipment Corporation
Architecture: PDP-11
A PDP-11/44 setup.


Quoting http://www.xs4all.nl/~geerol/en/GAL/index.html (1979) The PDP 11/44 (hostname "gigant") is a low-cost successor of the PDP 11/70. The 11/70, brought to the market in 1975, was the first "large" PDP. Large means a 22 bit address space and a memory limit of 4MB. Do keep in mind that user programs are still limited to 16 bit addressing and hence restricted to a limit of just 2x 64KB, when using separated I&D.

The cost of a new 11/44 has been about half of the listprice of an 11/70. The PDP 11/44 had no Massbus like the /70 has, so it was not possible to use diskdrives with a transfer rate too high.


Quoting: 1979. A middle-class -11. It had the 22-bit UNIBUS map and MMU as standard (up to 2 Mwords on a separate CPU-memory interconnect, called the PAX Memory Bus). The CPU consists of 5 boards, plus one for the FPP (FP11-F, optional), and two CIS (KE44-A, optional). Features: 8 KByte cache, ODT, 2 SLU's (Serial Line Units: console + TU58 console media), RTC (Real-Time Clock), kernel/supervisor/user modes.

The machine also had an almost-FEP (front-end processor) console, based on the Intel i8088, running from PROM. There was no qbus equivalent.

Trivia: This was the last non-microprocessor-based PDP-11 (it used LSI bitslice processors).