---
title: Research Machines RM-380Z
categories:
- Computers
types:
- Professional Computer
origins:
- United Kingdom
years:
- '1977'
cpus:
- Z80-A
params:
  name: RM-380Z
  image: /media/museum/photos/researchmachines_rm380z_system_1.jpg
  company: /companies/research-machines
  company_name: Research Machines
  specs:
  - label: NAME
    value: RM-380Z
  - label: MANUFACTURER
    value: Research Machines
  - label: TYPE
    value: Professional Computer
  - label: ORIGIN
    value: United Kingdom
  - label: YEAR
    value: '1977'
  - label: BUILT IN LANGUAGE
    value: None
  - label: KEYBOARD
    value: Full stroke 60 keys QWERTY layout
  - label: CPU
    value: Z80-A
  - label: SPEED
    value: 4 MHz.
  - label: CO-PROCESSOR
    value: None
  - label: RAM
    value: 4 KB expandable to 56 KB
  - label: ROM
    value: 2 or 3 KB (Monitor)
  - label: TEXT MODES
    value: 40 chars (later optional 80) x 24 lines
  - label: GRAPHIC MODES
    value: |-
      80 x 72 monochrome as standard\
      320 x 192 16 colours and 640 x 480 4 colours with optional HRG board
  - label: COLORS
    value: Monochrome or 256 colours (HRG option)
  - label: SOUND
    value: None
  - label: SIZE / WEIGHT
    value: 59.5 (W) x 42.5 (D) x 21.5 (H) cm
  - label: I/O PORTS
    value: UHF TV, Composite video, Tape recorder, Parallel printer
  - label: BUILT IN MEDIA
    value: Single or dual 5.25
  - label: OS
    value: CP/M
  - label: POWER SUPPLY
    value: Built-in power supply unit
  - label: PERIPHERALS
    value: Graphic and colour board, 8'' 500 KB floppy drives
  - label: PRICE
    value: From £519
  tabs:
  - links
  forum_thread: 793
  links:
  - title: Research Machines RML380Z and 480Z Yahoo Discussion Group
    url: http://tech.groups.yahoo.com/group/380z/
    text: All is in the title...
  oc_id: 812
  source:
    url: https://web.archive.org/web/20230605231027/http://www.old-computers.com/museum/computer.asp?c=812
    date: '2023-06-05'
---

Research Machines is based in Oxford, England and the RM-380Z was their first model. It was designed specifically for the education market and the vast majority of its users were in this area.

The computer was based around the Z80A processor. It had a clever physical bus made of ribbon cable with IDC crimp on connectors obviating the problems of poor connections associated with edge connectors.

The basic system was composed of a 4 KB main unit, a typewriter style separate keyboard and a monochrome monitor. Single or dual floppy disc drives could be inserted in the main housings. 8" floppy drives (2 x 500 KB) were also available as well as a ‘High resolution’ colour graphics board.\
The CP/M operating system was used to run lots of educational software.

Before and during the time that the BBC computers were introduced in English schools, the 380Z and its successor the [Link 480Z](/museum/research-machines-link-480z/) met a great success, mostly due to their high reliability.

The RM-280Z should be the kit version of the 380Z but RM never shipped any kits but only pre-built 380Z machine, thinking better of the support problems it would cause.

---

Cassette tape version, by **Simon Elliott**:\
I seem to recall using an early version of the RM380Z that used to load the OS from cassette tape, not floppy disk.\
Once loaded, if the reset button was pressed, the 'J103' trick could be used to bypasss the reload; but the initial load was a real pain.\
When the school I was attending purchased the disk drive and memory upgrade, all us CS students thought we'd entered computer heaven. ;-)\
I also recall a very primitive add-on sound option, beeps from something not unlike a modern PC speaker.

**Gary** adds:\
The 5.25" floppy drives were renowned for sudden failure caused by the rubber drive band coming off the drive. It was a simple matter to pop open the lid and re-seat the band.

**Ben Jones** remembers:\
I remember using a 380Z in Canterbury, around 1980. As well as the excellent text editor (can't remember what it was called now, but I found nothing comparable for a decade afterwards), I loved the simplicity of programming it in assembler.\
Two geeks I knew used to hang out in the school's computer room, one writing a version of Defender in 6502 Assembler on the BBC, the other writing Space Invaders in Z80 on the 380Z (I myself did a PacMan-like game on the 380Z - and I've still got the floppies). Any time the Space Invaders code hung, its author would pause an instant, look up, sniff, comment that he "could smell the 380Z's hi-res board burning" and dive for the white button. :-)\
But best of all was the fact that even after a 'hard reset' like that, you simply had to enter "J103" to jump back to where you were before ("J100" did a full reboot). I think 0103 as a recovery address stayed around for years (or even decades) -- disassemble any .com programme even now, and you'll probably find that the first, 3-byte, instruction at 0100 jumps to the main start routine, while the next one jumps somewhere else. Oh if only that worked with Windoze... :-(