website/content/museum/sega-mark-iii.md

---
title: Sega Mark III
categories:
- Consoles
params:
  name: Mark III
  image: /media/museum/photos/sega_mark3_1s.jpg
  company: /companies/sega
  company_name: Sega
  tabs:
  - photos
  - connectors
  - emulators
  - links
  - videos
  forum_thread: 787
  photos:
  - title: SEGA MARK III
    subtitle: ''
    text: Thanks to Rikard Ljungkvist for this picture
    image: /media/museum/photos/sega_mark3_1b.jpg
  - title: BOTTOM
    subtitle: ''
    text: Thanks to Rikard Ljungkvist for this picture
    image: /media/museum/photos/sega_mark3_bottom.jpg
  - title: REAR
    subtitle: ''
    text: |-
      From left to right:

      \- RGV video output\
      \- Channel select switch\
      \- RF video output\
      \- Power in\
      \- Power on/off switch

      Thanks to Rikard Ljungkvist for this picture
    image: /media/museum/photos/sega_mark3_rear.jpg
  - title: MARK III WITH CARTRIDGE
    subtitle: ''
    text: ''
    image: /media/museum/photos/sega_mark3_2.jpg
  - title: CONTROLLER
    subtitle: ''
    text: ''
    image: /media/museum/photos/sega_mark3_controller.jpg
  - title: SKETCH
    subtitle: ''
    text: ''
    image: /media/museum/photos/sega_mark3_sketch.jpg
  connectors:
  - title: A/V CONNECTOR PINOUT
    subtitle: ''
    text: This is the same pinout as the Genesis / Megadrive "1", and Master System.
    image: /media/museum/connectors/genesis_md_sms_mkiii_video.gif
  - title: JOYSTICK CONNECTOR
    subtitle: ''
    text: Same pinout as the SG-1000 and the Master System
    image: /media/museum/connectors/sms_joystick.gif
  emulators:
  - title: Dega
    url: http://www.mameworld.net/easyemu/degatut.htm
    platform: Windows
    text: SMS, Mark III and Game Gear emulator
  - title: MEKA
    url: http://www.smspower.org/meka/
    platform: Windows
    text: Multi-system emulator (SG-1000, Mark III, SMS, SC-3000, Game Gear, Colecovision, Othello Multivision)
  - title: Past-O-Rama
    url: http://www.system16.com/pastorama/
    platform: Windows
    text: Sega systems emulator
  links:
  - title: Enri's Sega Mark III page
    url: http://www2.odn.ne.jp/~haf09260/Mark3/EnrM3.htm
    text: Very complete hardware information page along schematics
  - title: GameFAQs
    url: http://www.gamefaqs.com/console/sms/game/22669.html
    text: Excellent site gathering several Sega Master System FAQs
  - title: Henri's Home-Page
    url: http://www2.odn.ne.jp/~haf09260/Mark3/EnrM3.htm
    text: Sega MK III japanese page
  - title: IGN.COM
    url: http://codes.ign.com/lists/20137/068/index.html
    text: A LOT of Sega Master System game codes
  - title: MEKA Software Database
    url: http://www.smspower.org/meka/wip/meka.nam
    text: Very precise and useful software database (SMS, GG, Coleco, etc.)
  - title: Official Mark III pages from Sega!
    url: http://www.sega.co.jp/archive/segahard/mk3/
    text: Excellent. Lot of info here (specs, pix, soft lists, ads,etc.)
  - title: Official Master System pages from Sega!
    url: http://www.sega.co.jp/archive/segahard/master/
    text: Excellent. Lot of info here (specs, pix, soft lists, ads,etc.)
  - title: Sega Mark III Web Page
    url: http://www6.airnet.ne.jp/tera/sega/
    text: Nice japanese site full of info
  - title: Sega Master System, the console legend
    url: http://www.geocities.com/snappa_fcw/sega.html
    text: SMS dedicated website. A lot of stuff here.
  - title: SMS Power
    url: http://smspower.speedhost.com/
    text: Excellent site supporting all Sega 8-bit systems
  - title: UK Sega Master System page
    url: http://www.severedbbs.u-net.com/fletcher/SMS.html
    text: History, pictures and tech info
  - title: www.alexkidd.com
    url: http://www.alexkidd.com/
    text: FAQs, Game reviews, hardware & peripheral pics and info, ads, links and much more
  - title: www.sega8bit.com
    url: http://www.sega8bit.com/
    text: Featuring a games database, release and rarity information, plus the most active SMS related forums on the web
  videos:
  - title: Sega Master System TV commercial
    url: https://www.youtube.com/watch?v=S5vreoJLLRM
    text: 'Length: 31s'
  related:
  - /museum/sega-master-system
  - /museum/sega-master-system-ii
  - /museum/sega-master-system-iii
  - /museum/sega-sg-1000
  - /museum/sega-sg-1000-mark-ii
  oc_id: 806
  source:
    url: https://web.archive.org/web/20230316165040/http://www.old-computers.com/museum/computer.asp?c=806
    date: '2023-03-16'
---

The Sega Mark III is the third version of the [SG-1000](/museum/sega-sg-1000/) system and was only released in Japan. This system is in fact the original Japanese version of the [Sega Master System](/museum/sega-master-system/).

Compared to the [SG-1000 Mark II](/museum/sega-sg-1000-mark-ii/) the case has been redesigned again, a video monitor output has been added, and the system is equiped with a card slot which was also found on the first version of the Master System. The Mark III is backwards compatible with the SG-1000 cartridges.

The system has an expansion port that can be used by add-ons, such as the FM sound unit or the Telecon Pack (wireless video signal). The controllers (two joypads), can still be stored on each side of the system. Many other add-ons were available (not using the expansion port though), such as several different controllers, 3D Glasses, keyboard, graphic board, etc.

When Sega decided to market the Mark III abroad they redesigned the case and sold it as the Sega Master System. Though superior technically, the SMS/Mark III was eclipsed by the great success of the [NES](/museum/nintendo-nes/)/Famicom.

<table> <tr> <td></td> <td>We need more info about this console ! If you designed, used, or have more info about this system, please send us pictures or anything you might find useful.</td> <td></td> </tr> </table>