---
title: Sega Teradrive
categories:
- Computers
types:
- Home Computer
origins:
- Japan
years:
- '1991'
cpus:
- Intel 80286
params:
  name: Teradrive
  image: /media/museum/photos/sega_teradrive_1.jpg
  company: /companies/sega
  company_name: Sega
  specs:
  - label: NAME
    value: Teradrive
  - label: MANUFACTURER
    value: Sega
  - label: TYPE
    value: Home Computer
  - label: ORIGIN
    value: Japan
  - label: YEAR
    value: May 1991
  - label: KEYBOARD
    value: Full-stroke professional keyboard. 106 keys with function keys, cursor keys and numeric keypad
  - label: CPU
    value: Intel 80286 + Motorola MC68000 + Zilog Z80A (used for sound system)
  - label: SPEED
    value: 10 MHz (80286) / 10 MHz (68000) / 3.58 MHz (Z80A)
  - label: CO-PROCESSOR
    value: Megadrive customchips (?)
  - label: RAM
    value: 2.5 MB (512 KB onboard + two 1 MB SIMM RAMs)
  - label: VRAM
    value: 256 KB
  - label: ROM
    value: 128 KB
  - label: TEXT MODES
    value: 40 or 80 chars x 25 lines
  - label: GRAPHIC MODES
    value: 320 x 244 (Megadrive VDP Mode) / 320 x 200 (MCGA) / 640 x 480 (VGA)
  - label: COLORS
    value: 64 among 512 (Megadrive Mode) / 256 among 262144 (S/VGA Modes)
  - label: SOUND
    value: FM Sound / PCM Sound (Megadrive) - Beeper (PC)
  - label: SIZE / WEIGHT
    value: 36 (W) x 33.4 (D) x 8 (H) cm / 5.6 to 6.2 Kg according to versions
  - label: I/O PORTS
    value: RGB analog vide output, composite video output, 1 ISA slot, mouse, keyboard, serial (2) & parallel (1) ports, headphone output, 2 joystick ports
  - label: BUILT IN MEDIA
    value: 3.5'' disk-drive, 30 MB hard drive
  - label: OS
    value: DOS/V
  - label: POWER SUPPLY
    value: Built-in PSU
  - label: PRICE
    value: 148,000¥ (Mod.1), 188,000 ¥ (Mod.2), 248,000 (Mod.3) (Japan, 1991)
  tabs:
  - photos
  - adverts
  - connectors
  - software
  - links
  - videos
  forum_thread: 512
  photos:
  - title: MAIN UNIT
    subtitle: ''
    text: ''
    image: /media/museum/photos/sega_teradrive_main-unit.jpg
  adverts:
  - title: JAPANESE ADVERT (1991)
    subtitle: ''
    text: This japanese advert indicates that there were at least 3 different models sold...
    image: /media/museum/pubs/sega_teradrive_jap-pub_1.jpg
  connectors:
  - title: SEGA TERADRIVE
    subtitle: RGB monitor pinout
    text: |-
      1 - Red\
      2 - Green\
      3 - Blue\
      4 - Horizontal/Composite Sync\
      5 - Vertical Sync\
      6 - Red Shield\
      7 - Green Shield\
      8 - Blue Shield\
      9 - Ground
    image: /media/museum/connectors/sega_teradrive_videou-output.jpg
  screenshots:
  - title: BOOT SCREEN
    subtitle: ''
    text: Start-up menu with several options, including file manager, DOS, clock and MegaDrive mode.
    image: /media/museum/software/sega_teradrive_boot.jpg
  links:
  - title: Assembler - Teradrive page
    url: http://assembler.roarvgm.com/teradrive/teradrive.html
    text: Some pictures & info here
  - title: Mic's homepage
    url: http://www1.odn.ne.jp/~caa09810/old_pc/pc_tera.htm
    text: Nice small japanese description
  - title: nfg.2y.net - Teradrive page
    url: http://nfg.2y.net/games/teradrive/
    text: Another interesting page in English
  - title: Qwerters Clinic
    url: http://www.ai.wakwak.com/~ex4/kb/main_sega_teradrive.htm
    text: Nice japanese page dedicated on the Teradrive's keyboard (!)
  videos:
  - title: Sega Teradrive - Japanese advert
    url: http://video.google.com/googleplayer.swf?docId=-4391346534753818861&hl=fr
    text: 'Length: 14 s'
  oc_id: 518
  source:
    url: https://web.archive.org/web/20230326085701/http://www.old-computers.com/museum/computer.asp?c=518
    date: '2023-03-26'
---

What a strange computer ! It was built by IBM (like the [Atari Jaguar](/museum/atari-jaguar/) few years later) in Japan for Sega, and was sold only there.

It is an [IBM PC AT](/museum/ibm-pc-at/) compatible system mixed with a Sega Megadrive (Genesis) console. On the front panel, one can find a Megadrive cartridge slot, two joystick connectors, a reset button, a MD/PC switch, a volume slider, a headphone output, a power button, keyboard/mouse connectors (PS/2) and one 3.5'' disk drive.

Three models were released, a low-end **Model 1**, with 640k RAM and no HD, a **Model 2** with two floppies and no HD and 1MB RAM, and the high-end **Model 3**, with one floppy, 2.5MB RAM and a 30MB drive. All three shipped with the same software and accessories.

Amstrad made later a similar computer called **MegaPC**.