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title, categories, types, origins, years, cpus, params
title categories types origins years cpus params
Digital Equipment Corporation DECmate III
Computers
Professional Computer
U.S.A.
1984
Harris 6120 cpu
name image company company_name specs tabs forum_thread photos links oc_id source
DECmate III /media/museum/photos/dec_decmate_iii.jpg /companies/digital-equipment-corporation Digital Equipment Corporation
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NAME DECmate III
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MANUFACTURER Digital Equipment Corporation
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TYPE Professional Computer
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ORIGIN U.S.A.
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YEAR 1984
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END OF PRODUCTION 1990
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KEYBOARD QWERTY full-stroke professionnal keyboard
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CPU Harris 6120 cpu (12 bits)
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SPEED 8 Mhz
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RAM 32k (+ 32k for dedicated control panel functions)
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TEXT MODES 80 x 24 and 132 x 24
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COLORS No
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SIZE / WEIGHT 32 x 28 x 14 cm / 8 kg
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I/O PORTS RS232C, printer, data-communication port
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BUILT IN MEDIA 2 x 5
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OS OS/278
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POWER SUPPLY Built-in PSU
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PERIPHERALS Color graphics board\ APU board : Z80 based board for CP/M use\ XPU board : 8088 based board for MS/DOS use\ Modem
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PRICE approx. 2700$
photos
links
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MAIN UNIT /media/museum/photos/dec_decmate3_system_s1.jpg
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DECmate FAQ by Charles J. Lasner http://www.ibiblio.org/pub/academic/computer-science/history/pdp-8/docs/dminfo.faq DECmate specific information
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PDP8 page by Douglas W. Jones http://www.cs.uiowa.edu/~jones/pdp8/ Infos and links about the PDP8 machines
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''What is a DECmate III ?'' from the PDP-8 FAQ http://www.faqs.org/faqs/dec-faq/pdp8-models/section-15.html Useful
468
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https://web.archive.org/web/20230202174529/http://www.old-computers.com/museum/computer.asp?c=468 2023-02-02

This computer is still based on the PDP-8 architecture but is less "opened" than the DECmate II. Indeed DEC realised that the PDP-8 based products were rarely expanded to their full potential. Thus, they conceived the DECmate III wich offers less expansion possibilities but which was also cheaper.
As the last incarnation of the PDP-8 technology, the DECmate III use a single chip containing all the PDP-8 hardware !

Only one pair of 5''1/4 disk-drives (RX50) is supported and it is not possible to connect a Hard-Drive. But unlike the DECmate II, a color monitor can replace the monochrom screen.

It was mainly intended for professionnal word-processing, but could also run other software including OS/278. The DECmate III was compatible with the DECmate II.

In 1985, a DECmate III+ was sold with a hard disk controller built-in and overall completely new hardware components, though still compatible with the DECmate II and III.

The DECmate computers were marketed by Digital Equipment Corporation.