website/content/museum/digital-equipment-corporation-decmate-ii.md

---
title: Digital Equipment Corporation DECMATE II
categories:
- Computers
types:
- Professional Computer
origins:
- U.S.A.
years:
- '1982'
cpus:
- 12 bit Harris 6120
params:
  name: DECMATE II
  company: /companies/digital-equipment-corporation
  company_name: Digital Equipment Corporation
  specs:
  - label: NAME
    value: DECMATE II
  - label: MANUFACTURER
    value: Digital Equipment Corporation
  - label: TYPE
    value: Professional Computer
  - label: ORIGIN
    value: U.S.A.
  - label: YEAR
    value: '1982'
  - label: END OF PRODUCTION
    value: '1986'
  - label: BUILT IN LANGUAGE
    value: None
  - label: KEYBOARD
    value: Full-stroke 106 keys with 20 function keys, editing and numeric keypads
  - label: CPU
    value: 12 bit Harris 6120
  - label: SPEED
    value: 4 or 8 MHz
  - label: RAM
    value: 32 K x 12bits
  - label: ROM
    value: 4 KB
  - label: TEXT MODES
    value: 80 chars x 24 lines / 132 chars x 24 lines
  - label: GRAPHIC MODES
    value: optional
  - label: COLORS
    value: monochrome
  - label: SOUND
    value: beeper
  - label: I/O PORTS
    value: Monitor, Serial, Printer
  - label: BUILT IN MEDIA
    value: |-
      1 or 2 x RX50 dual 5.25'' floppy disc drives\
      Optional 5, 10 or 20 MB hard disk
  - label: OS
    value: COS 310
  - label: POWER SUPPLY
    value: Built-in switching power supply unit
  - label: PERIPHERALS
    value: Z80 card, Graphic colour card, 8088 card, MFM H.D. controller card
  - label: PRICE
    value: $1435
  tabs:
  - photos
  - adverts
  photos:
  - title: 'TOWER STAND #1'
    subtitle: ''
    text: The Decmate II is here inserted into the optional tower stand.
    image: null
  - title: 'TOWER STAND #2'
    subtitle: ''
    text: Tower stand Back side
    image: null
  - title: IN USE
    subtitle: ''
    text: |-
      Word processor software in use.

      Notice that the keyboard supplied with the DECmate was in fact exactly the same as the one used with the DEC VT200 and VT300 series terminals.
    image: null
  - title: RX50 FD UNIT
    subtitle: ''
    text: Dual 5.25" floppy disc unit
    image: null
  - title: INSIDE RX50
    subtitle: ''
    text: This very particular floppy drive unit uses common motors and electronic board for managing both drives
    image: null
  - title: BACK SIDE
    subtitle: ''
    text: |-
      **(1)** Brightness and contrast adjustments\
      **(2)** Keyboard RJ11 jack\
      **(3)** Colour graphic video connector. Only available when the optional graphic board is installed\
      **(4)** Monochrome video connections\
      **(5)** Printer connector\
      **(6)** Serial connector.
    image: null
  - title: 'INSIDE #1'
    subtitle: ''
    text: Like most of DEC desktop systems, hardware design is well thought out and modular. Motherboard can be taken off like a drawer, as well as mass storage units. Power supply unit also can be taken apart in less than 5 seconds
    image: null
  - title: 'INSIDE #2'
    subtitle: ''
    text: |-
      Full system including a 5.25" full size 5 MB Seagate ST-506 hard disk.

      Seagate 10 MB (ST-412) or 20 MB (ST-225) could be installed too.
    image: null
  - title: MAIN BOARD
    subtitle: ''
    text: |-
      **(1)** Expansion connectors for optional boards\
      **(2)** Floppy drive connectors
    image: null
  - title: OPTION CARDS
    subtitle: ''
    text: |-
      **(1)** Z80 card along with 64 KB of CP/M RAM\
      **(2)** Winchester hard disk controller card\
      **(3)** Colour graphic card.
    image: null
  - title: DECMATE MANUALS
    subtitle: ''
    text: Digital Hardware and software manuals are very clear and detailled.
    image: null
  adverts:
  - title: US ADVERT (1982)
    subtitle: ''
    text: |-
      This advert introduced three new Digital professional computers: the **Professional 300 Series**, the **DECmate II**, and the **Rainbow 100**

      Advert said:

      All that personal computers needed were a few professional standards.

      Until now, manufacturer have made personal computers that were a hopeful compromise between home and use business. But now, Digital Equipment Corporation offers the first personal computers designed and built strictly for professional use. And since different professionals have different needs, Digital is introducing not one, but three personal computers made to professional standards.
    image: null
  comments:
  - author: Iwin Zane (USA)
    date: Wednesday 25th April 2012
    text: The DECmate computer systems all required a bootable 5.25 inch floppy diskette which contained the OS as well as the WPS software. They could also run the COS310 Operating System which after some modification by Digital Research Corp. became CP/M. With the addition of the Z80 board, they were able to run MS-DOS. As the only authorozed dealer in Southern California, I and my staff had great sales experiences with it. Incredibly, we still have some in inventory, as well as brand new DECmate IIIs.
  - author: Steven Monrad (US)
    date: Wednesday 23rd December 2020
    text: Not all Decmates required booting and loading software from a floppy disc. We got one about 1980 which did. New $4,500 USD. Another a year later with a CP/M board and Winchester hard drive, which contained the CP/M OS and the original PDP-8 emulation. $400 USD used. Chosen over the Rainbow and the Apple II for the dedicated WP incorporated in the PDP 8 version, dedicated WP keyboard, and the 132 column ''screen shift'' beyond the std 80 column screen view. All USA made.Ran a construction co with the WP and Visicalc running on CP/M. We first saw the IBM Winchester drives working at NCR, another once-leading company that vanished. Ken Rosen at DEC stated that there was no future for the computer in the home about that time.
  - author: Chuck (United States)
    date: Thursday 1st June 2017
    text: '@Steve: In order to run CP/M on this machine, you needed to get the Z80 expansion card with 64k RAM. This allowed this machine to use CP/M AND run most PDP 8 software.'
  - author: Steve (USA)
    date: Thursday 19th January 2017
    text: Actually, CP/M PREDATES the DECMATE WPS series! The system was certainly not like CP/M. Digital AKA DEC, was not related to Digital Research. Digital Research CP/M required an 8080 processor. The Z80 was 8080 compatible, but the PDP 8 was NOT. CP/M did NOT support the 8086 series of processors, like those MSDOS did.
  - author: Irwin Zane (LOS ANGELES/USA)
    date: Tuesday 24th April 2012
    text: This powerful (in its day) little computer was built like an Abrams tank. The word processing software was unbeatable and the power supply was designed to last forever. As the only authorozed dealer in Southern California, I and my staff had great sales experiences with it.
  - author: Ron Cooper (Tennessee, USA)
    date: Friday 14th January 2011
    text: The Z-80 card was also required for the optional spell checker function in WPS. With the Z-80 and CP/M, you could run VisiCalc and later Lotus 123 and dBase.
  oc_id: 845
  source:
    url: https://web.archive.org/web/20230601212724/http://www.old-computers.com/museum/computer.asp?c=845
    date: '2023-06-01'
---

The DECMATE II shared the same case, power supply unit and RX50 dual floppy drive as the [Rainbow 100](/museum/digital-equipment-corporation-rainbow-100/) and was sold as a desktop or tower stand system. Like DECMATE I and [III](/museum/digital-equipment-corporation-decmate-iii/), it was a member of the PDP-8 family based on the Harris 12-bit 6120, a single chip PDP-8 compatible microprocessor.

It had 32 Kwords of RAM for use by programs, and a further 32 Kwords containing code which was used for device emulation.

The same year, DEC launched the [Rainbow 100](/museum/digital-equipment-corporation-rainbow-100/), a Z80/8088 based system to compete with CP/M and MS-DOS machines, as well as the [300 Professional](/museum/digital-equipment-corporation-300-professional-series/) systems.

The DECMATE II was the Decmate series most versatile system. Customer could choose between either one or two dual 5.25" floppy disc drives, or a 5, 10 or 20 MB hard disc, or even 8" floppy drives. Several option boards were also available. Among them, a Z80 card for CP/M compatibility and a graphic board allowing a color monitor to be used.

Digital corporation provided a large range of professional software. However, the Decmate II was mainly used for professional word processing, connected to a serial letter quality printer.

Special thanks to **David Cheeseman**