website/content/museum/research-machines-link-480z.md

---
title: Research Machines LINK 480Z
categories:
- Computers
types:
- Professional Computer
origins:
- United Kingdom
years:
- '1981'
cpus:
- Z-80A
params:
  name: LINK 480Z
  company: /companies/research-machines
  company_name: Research Machines
  specs:
  - label: NAME
    value: LINK 480Z
  - label: MANUFACTURER
    value: Research Machines
  - label: TYPE
    value: Professional Computer
  - label: ORIGIN
    value: United Kingdom
  - label: YEAR
    value: '1981'
  - label: BUILT IN LANGUAGE
    value: Microsoft BASIC interpreter
  - label: KEYBOARD
    value: Full-stroke with 4 cursor controls and 4 user definable keys
  - label: CPU
    value: Z-80A
  - label: SPEED
    value: 4 Mhz.
  - label: RAM
    value: 32 KB up to 256 KB
  - label: VRAM
    value: 16 KB (expansion board)
  - label: ROM
    value: 8 KB up to 32 KB
  - label: TEXT MODES
    value: 40 or 80 chars. x 25 lines
  - label: GRAPHIC MODES
    value: 640 x 192 monochrome, 320 x 192 (4 colours), 160 x 95 (8 colours)
  - label: COLORS
    value: Up to 8
  - label: SOUND
    value: built-in tone generator and speaker
  - label: SIZE / WEIGHT
    value: 53(W) x 33.5(D) x 8(H) cm / 3.2 Kg.
  - label: I/O PORTS
    value: Composite, RGB and aerial video outputs, IEEE-488, Network, Serial x 2, Parallel, Tape recorder, Analog
  - label: BUILT IN MEDIA
    value: Tape recorder or optional 5'' F.D. drive
  - label: OS
    value: Microsoft Basic or CP/M
  - label: POWER SUPPLY
    value: Built-in power supply unit
  - label: PERIPHERALS
    value: Single or dual 5'' F.D. drives unit, Multi I/O expansion board
  - label: PRICE
    value: $650
  tabs:
  - photos
  - hardware
  - links
  - docs
  photos:
  - title: CP/M SYSTEM
    subtitle: ''
    text: The most widely used CP/M configuration with a single or dual F.D. drives unit and a graphic monitor (here a Microvitec CUB 14" color monitor)
    image: null
  - title: BLACK VERSION
    subtitle: ''
    text: Black metallic case version. Probably the first version of the 480Z.
    image: null
  - title: 'INSIDE #1'
    subtitle: ''
    text: |-
      The basic version motherboard with only one option: the four Microsoft extended BASIC ROM chips.

      **(1)** Network socket\
      **(2)** Network card housing\
      **(3)** Mostek 8227 chip in charge of various input/output tasks\
      **(4)** Network address selection dip-switches\
      **(5)** Serial DIN plug 1\
      **(6)** Serial plug #2. Used by the floppy-disk unit\
      **(7)** Parallel connector\
      **(8)** Tape recorder DIN plug\
      **(9)** Accessories connector\
      **(10)** Monochrome composite monitor output\
      **(11)** T.V. aerial modulator\
      **(12)** Test label "Tested by C.H. 18/9/83" (Thanks C.H.!)\
      **(13)** 2 KB text video RAM chip (6116)\
      **(14)** Monitor and BASIC language ROM chips\
      **(15)** 64 KB RAM chips\
      **(16)** Z80 microprocessor\
      **(17)** Expansion board connector\
      **(18)** Network card connectors
    image: null
  - title: 'INSIDE #2'
    subtitle: ''
    text: |-
      Full version with expansion and network boards.

      **(1)** Power supply unit\
      **(2)** Fan\
      **(3)** Additional 64 KB RAM chips\
      **(4)** IEEE 488 connector (IEEE 488 hardware is not installed on this board)\
      **(5)** RGB output (DIN plug)\
      **(6)** The network card is located between the motherboard and the expansion board
    image: null
  - title: BACK SIDE
    subtitle: ''
    text: |-
      **(1)** Color TTL / RGB video output\
      **(2)** IEEE 488 optional connector housing\
      **(3)** IEEE 488 optional address switches selection\
      **(4)** Mains power cord, fuse and On/Off switch\
      **(5)** Network coaxial plug\
      **(6)** Network address selection switches\
      **(7 - 8)** Serial RS-232 DIN plugs. The floppy disk unit is connected to the left one.\
      **(9)** Parallel I/O connector\
      **(10)** Tape recorder DIN plug\
      **(11)** Analog accessories DIN plug\
      **(12)** Monochrome composite video output (monitor)\
      **(13)** Reset switch\
      **(14)** T.V. aerial output
    image: null
  hardware:
  - title: DUAL 5'' F.D. UNIT
    subtitle: ''
    text: ''
    image: null
  - title: INSIDE F.D. UNIT
    subtitle: ''
    text: |-
      **(1)** The logical card is a true computer with a Z80 microprocessor, ROM and RAM memories, Z80-CTC and Z80-PIO for the data exchanges management.\
      **(2)** Floppy drives came from YE-DATA (Japan). There are double side, double density, 320 KB models.\
      **(3)** Power supply unit
    image: null
  links:
  - title: Research Machines RML380Z and 480Z Yahoo Discussion Group
    url: http://tech.groups.yahoo.com/group/380z/
    text: All is in the title...
  docs:
  - title: BASIC INTERPRETER REFERENCE MANUAL
    url: '#'
    cover: null
    text: |-
      **BASIC INTERPRETER REFERENCE MANUAL**\
      written by Research Machines - Thanks to **Jonathan Hudson**

       type of document : ZIP\
       source : old-computers.com
  comments:
  - author: Richard (UK)
    date: Saturday 24th September 2016
    text: In our secondary school computer lab in Banbury we had eight of these around the edges of the classroom. I''m sure we did some LOGO type programmes on them. There was an BBC Archimedes 310M in the corner running Arthur (RiscOS) and a PC emulator. We weren''t allowed to touch the Arch.
  - author: Jon
    date: Friday 6th December 2013
    text: I remember my primary school getting one of these. It was on a huge wooden trolley with the monitor etc. and each class would take it in turns to have it for half a day. The first time our class had it the teacher eventually managed to get a program running that taught us all how to tell the time! I thought it was all so futuristic!
  - author: Ash (Didcot, United Kingdom)
    date: Wednesday 31st August 2011
    text: We had 480Z''s in secondary school linked to a twin floppy 380Z "server" at the front of the classroom. I remember the teacher $ing 2x discs which I think had the same content and then instructing us to wait until he''d loaded the program onto his 480Z first. Then it would be our turn, with the workload split between the two server drives - a kind of load balancing system. Best way to wind up the teacher was for the entire class to jump the gun in unison $ get loading first!
  - author: ghoolster
    date: Sunday 5th December 2010
    text: Goto the yahoo group 380z, have posted answer there...
  - author: Dave (UK)
    date: Saturday 18th September 2010
    text: I have a 480Z and an MD1 floppy drive in the loft, I''d been after them for years.... I didn''t get the serial cable that connects them together though. Does anyone out there know how to wire one up? Cheers, Dave
  - author: Carl (Los Angeles)
    date: Wednesday 21st November 2007
    text: |-
      God, I remember we used these back when I was in high school, back when I grew up in the UK. I can recall writing my first text adventure on it, and trying hard to redo an old text adventure I had wrote on my old Vic-20 and C64.

      Memories...
  - author: Christine (suffolk)
    date: Wednesday 2nd November 2005
    text: I have to say that we also have an RM480Z that has been in daily use in the Nursery school since its purchase in 1983 and the Nursery teacher will NOT let go of it- she is very protective of it- eben though she also has an up to date pc too. we still have a few spare parts for when it has a headache but still going strong!!
  - author: Darren (UK)
    date: Friday 8th April 2005
    text: I used to repair these, and remember poking the memory to find out which memory chip had failed....CTRL-F if I remember correctly? Now I can't add up, due to the binary involved in diagnosing these! The black metal ones hurt if you drop them on your foot....but parts were interchangeable between the two models..
  - author: jc (Leamington Spa)
    date: Thursday 10th October 2002
    text: |-
      My dad worked for RM back "in those days", and we had both a 380Z and a 480Z in the house. The 480Z died a death, but I think the 380Z's still up in the loft. Great big black boxes!!

      Anyone got any use for it, if I can pry it out of my dad's hands?

      jc
  - author: Robert (Manchester (UK))
    date: Wednesday 12th June 2002
    text: |-
      380Z was previous machine, it was just a black box with drives in it and a couple of ports of keyboard and screen.

      You could link the 480Z's together to form a network and used our old 380Z as a 'server'.

      You could recover programs from a crash by making a machine call on startup. I can't remember the call but I see to remember the address for '102'. It WAS 20 years ago mind.
  oc_id: 600
  source:
    url: https://web.archive.org/web/20230529181401/http://www.old-computers.com/museum/computer.asp?c=600
    date: '2023-05-29'
---

The Link 480Z was meant originally as a disc-less network station. It was designed to offer a lower cost computer to schools. The name "Link" meant link in a chain. It was a very reliable system, and one of the first personal computers used in the English schools.

Because of the good reputation of the Research Machines computers, the Link 480Z was one of the three computers chosen for the U.K. 1982 Educational Scheme, with the [Sinclair Spectrum](/museum/sinclair-zx-spectrum/) and the [BBC Model B.](/museum/acorn-computer-bbc-model-a-b-b/)

The basic version (cassette based with 32 KB of RAM and 8 KB ROM Monitor) could be extended to a real professional CP/M based system with network ability.

An optional expansion board added:\
\- 32 KB of RAM\
\- Colour or monochrome high resolution graphics (up to 640 x 192)\
\- Full IEEE 488 and colour RGB monitor interfaces\
\- Floppy disc interface in single, double or quad density modes

The 480Z was fully compatible with the 380Z. It was initially released in a black metal case prior to tooling being made for the subsequent beige plastic case version.