View source for PDP-11/03

{{Infobox Machine
| name = PDP-11/03
| manufacturer = [[Digital Equipment Corporation]]
| bus arch = [[QBUS]]
| year introduced = 1975
| architecture = [[PDP-11]]
}}

[[Image:Pdp11-03.JPG|150px|right|thumb|PDP-11/03]]

The '''PDP-11/03''', which initially shipped with the new [[LSI-11]] [[Central Processing Unit|CPU]], marked a major change in the [[PDP-11]] family in two ways:

* it was the first PDP-11 to essentially use a [[microprocessor]] (although the [[LSI-11 chip set]] was 4 [[integrated circuit|chips]], not 1, it was effectively a microprocessor);
* it was the first to use a new system [[bus]], the [[QBUS]], which used fewer [[conductor|lines]] (thus allowing [[printed circuit board|cards]] which plugged into QBUS [[backplane]]s to have fewer contact fingers), thereby reducing costs.

== hampage.hu ==
Quoting:

: ''1975. With the use of LSI semiconductor technology (the [[LSI-11]] and [[LSI-11/2]] processor), it was a compact implementation of the -11 architecture. It was limited though, to 32KW memory, only one processor operating mode, and limited floating-point instructions (the [[FIS floating point|FIS]]). Available options: CIS, WCS, EIS/FIS.''

: ''The /03 used the new LSI bus, later known as the [[QBUS]], and was aimed at the low-end market, as the successor of the /05. The slowest of the -11s (one third of the 11/20's performance).''

A PDP-11/03 was also used as the [[diagnostic]] and control unit for the [[VAX-11/780]]'s CPU; it would [[bootstrap]] the system.

{{semi-stub}}

==External links==

* [http://www.bitsavers.org/pdf/dec/pdp11/1103/ -11/03] - documentation at [[Bitsavers]]
** [http://www.bitsavers.org/pdf/dec/pdp11/1103/EK-LSI11-TM-002.pdf LSI-11, PDP-11/03 user's manual] (EK-LSI11-TM-002)
** [http://www.bitsavers.org/pdf/dec/pdp11/1103/1103_Schematics.pdf PDP-11/03 engineering drawings]
** [http://www.bitsavers.org/pdf/dec/pdp11/1103/Titelbaum_LSI-11_1975.pdf The LSI-11 - A System Microcomputer]
* [http://bitsavers.org/pdf/dec/pdp11/EK0LSIFS-SV-005_LSI-11_Systems_Service_Manual_Volume_3_Jan85.pdf LSI-11 Systems Service Manual - Volume III] (EK-LSIFS-SV-005)
* [http://vtda.org/docs/computing/DEC/Handbooks/EB-05583-75_LSI11PDP11-03ProcessorHandbook_1975.pdf lsi11 pdp11/03 processor handbook]
* [https://link.springer.com/content/pdf/10.3758/BF03205335.pdf A source handbook for Digital Equipment Corporation LSI-11-compatible products]

{{PDP-11}}

[[Category: QBUS PDP-11s]]