Sega CD 101: A Beginner’s Guide

Note from racketboy: Special thanks goes to Scooter for putting this guide together!  The RetroGaming 101 series is aimed at gamers who are just starting out in the classic gaming scene or are curious about an older console that they don’t know much about yet. 

After Sega established a strong lead in the console market in the early 1990’s, the company saw the possibilities that the new CD-ROM format could bring to gaming.  Sega produced the Sega CD add-on for the Genesis to bring the technology to the many Genesis owners around the world without requiring them to invest in a completely new system.  Unfortunately, they did not completely follow through with their vision.  Even though it was not a commercial success, that does not mean that a Sega CD isn’t worth picking up for a reasonable price to expand on one’s classic Sega collection.  The Sega CD is still an interesting piece of hardware and has some games that are still worth checking out.

Note:  Sega’s 16-bit wonder was titled the Mega Drive in all markets except North America where the name had previously been copyrighted and was thus named the Genesis in that market.  For purposes of this article, the term Genesis will be used but should be noted that it is interchangeable with the name Mega Drive.  Appropriately, the Sega CD was named the Mega CD outside North America and in this article the term Sega CD will be used but should be noted that it is interchangeable with the name Mega CD.

Historical Impact

  • Sega CD was the first peripheral offered by Sega intended to expand the capabilities of and extend the life cycle of a basic gaming console (the Genesis).
  • While the Sega CD was not the first unit to bring optical disc technology to a gaming environment, it was the most widely distributed unit in its day.
  • The system attempted to fill the technology and release date gaps between a waning console (Genesis) and the next generation (Saturn).  Sega hyped the add-on quite well to keep bleeding-edge gamers from switching sides.
  • The shortcomings of the system (price, limited unique library) and the subsequent lack of success of the unit in the marketplace was the first major misstep by Sega in the hardware market.  This and additional missteps led to some amount of consumer mistrust and played at least a part in the eventual exit of Sega from the hardware market.
  • A number of Sega CD games were exclusive to the system and also sold in limited quantities making these games some of the most highly collectible games for the more mainstream retro console market.
  • Sega CD provided full motion video (FMV) as a video game element to the masses.  While not the first system to provide such a graphical interface, FMV was heavily pursued as the “wave of the future”.
  • Provided access to games otherwise relegated to a PC-only environment due to the increased data storage capacity of the CD media.
  • More information on the Sega CD on Wikipedia



  • The Sega CD expands the Genesis library (albeit, many games are available in both Genesis and Sega CD formats).
  • The systems are fairly reliable and durable.
  • The systems also function as a full featured audio CD player.
  • Both main versions are compatible with all Genesis consoles released by Sega.
  • The CD based media can provide lengthy and CD audio quality soundtracks, sound effects and voice to the game playing environment.
  • When properly installed, the system mixes the Genesis, Sega CD, and if also installed, 32X audio into a single stereo output source.  The stereo signal provided by the Sega CD unit is overall superior to the signal provided by the Genesis alone.
  • Very simple and easy to use operating controls.
  • The systems have built in game save memory (although the memory capacity is relatively small).
  • The units are only moderately sought after, especially the Sega CD-2 and as such can typically be acquired at moderate cost.
  • Exceptionally good system exclusive games justify the cost of acquiring and installing the system.


  • The system never sold in large numbers even though it was widely distributed in all major markets.  Finding complete boxed system can be difficult.  This is especially true of the first version.
  • Much of the software library for the add-on system is either rehashed pre-existing Genesis games with little to no additional features on the CD version of the game or shovelware.  A good portion of the game library consists of FMV based games.
  • Many games experience excessively long load times at the initial game load and inside the game, especially when loading upcoming video segments.
  • North American game packaging is bulky and fragile.
  • The system is bulky and will greatly increase either the vertical (version 1) or horizontal (version 2) space needed to house the unit when attached to a Genesis console.
  • The systems are not compatible with the Genesis 3 distributed by Majesco.


  • A number of region-specific games can provide an expanded library of games to those willing to address the technical requirements to make access to such games possible given their home television environment.  For example, North American based units can have easy access to Japanese games with the use of a cartridge slot based unit such as the Game Genie, yet access to European based games can potentially require much more involved technical accommodations.

Playing Backups (Burned Discs)

  • No modifications are needed to play burned discs on the Sega CD.  CD burners were extremely expensive at the time of the Sega CDs release, so there is not any copy protection implemented.
  • If you need turtorials for burning discs, please check out these guides for Windows, Mac OS, and Linux
  • If you want to be able to rip your own CD games to files, here’s a guide for Windows



  • Since the units sold were roughly 1 Sega CD for every 5 Genesis console sold, Sega CD consoles are not entirely common nor entirely rare.  The initial popularity tends to carry over to today allowing the retro gamer to obtain a Sega CD relatively easily and relatively affordably.  Functioning systems can be obtained for less than $50.
  • Complete boxed systems can command higher prices, easily reaching into the $100-$125 range and higher, especially for the first version of the system which is somewhat less common than the second version.
  • Some of the more uncommon configurations can be quite uncommon and command substantial prices often exceeding $200, much more for some of the even more rare configurations.
  • Many of the more popular games can be obtained locally in larger cities with stores which cater to older games for $10 or less.  Loose games without packaging can often be obtained for just a few dollars.

Hardware Variations

  Model 1
This unit is sometimes referred to as the front loader model.  This model sits entirely underneath the Genesis unit and shares the same footprint size as the Model 1 Genesis.  This unit is compatible with all Model 1 and Model 2 Genesis units, though it is more aesthetically matched to the Model 1 unit.  This item is somewhat more rare, more collectible and therefore more expensive even though it is considered somewhat less reliable than the later version.  Malfunctions in the sliding disc tray are usually the most common failure point.
Model 2
This unit is sometimes referred to as the top loader model.  The unit sits partially under and partially beside the Genesis unit.  The disc drive section of the unit is placed to the side of the Genesis with the remainder being under the Genesis, thus requiring a substantially larger footprint than the Genesis model alone.  However, since the moving disc tray mechanism of the Model 1 version is no longer present, this unit is typically considered overall more reliable.  Model 2 versions were produced in much larger numbers than the Model 1 version and as such are easier to locate and less expensive to obtain.  These units are compatible with both the Model 1 and Model 2 Genesis units though are more aesthetically matched to the Model 2 Genesis
Sega CDX
This is a relatively compact unit that combines the hardware of both the Genesis and Sega CD into one relatively small unit.  The unit provides two control pad outputs at the front, a small array of CD system control buttons at the front top edge, a CD system door in the middle top and a cartridge slot at the top rear.  AV outputs and AC inputs are found on the sides of the unit.
  JVC X’eye/WonderMega
These units combine the Genesis and Sega CD hardware into one complete package.

Sega CD Software

  • Approximately 200 games were made for the Sega CD, yet a good portion of that library was also available in similar form as Genesis cartridge based games. Some Sega CD games include exclusive content, most often in the form of expanded cut scenes or an expanded soundtrack, yet seldom in actual game play enhancements or additional levels or actual game content.
  • A handful of games were entirely exclusive to the Sega CD such as Heart of the Alien and Snatcher and a number of Working Designs RPGs and as such these games are highly desirable and can be expensive to obtain.
  • A good portion of the Sega CD library also contains games based in part or in whole on Full Motion Video (FMV) which are live video clips that are used as the basis for the game play.  Given the system’s limited graphics ability the graphics are typically grainy and lacking color depth and game play itself is somewhat limited.  Most FMV games have a quirky, “you either hate it or love it” feel to them.
  • Genesis 32X CD – A total of five games were made which exploited both the Sega CD and the 32X hardware (since all three pieces of hardware are required to play these particular games).  All five games are FMV games.  The games do provide modestly improved color and video resolution, but the video quality is still quite low.  None of the games were exclusive to the 32X CD format (all were available on the more accessible Sega CD format).
  • Games That Defined The Sega CD –  Unfortunately for those that had a Sega CD in its prime time, most of the best games for the console were not widely available or promoted much. While publishers were mainly promoting quick ports of popular Genesis titles with enhanced sound like NBA Jam and Full Motion Video games like Slam City with Scottie Pippin, there were actually a very nice collection of unique RPGs, shooter, and platformers that are still relevant to today’s hardcore gamers. So, instead of focusing on what games defined the Sega CD when it was on store shelves, we highlight games that motivate retro gamers to actually pick up a Sega CD in this modern era.
  • The Cheapest Sega CD Games Worth Your Time – If you want to build your Sega CD collection quickly on a budget, take a look at this guide to get your the values


  • Memory Cartridges:  Memory carts greatly expanded the memory capacity of the Sega CD unit.  Some games are so memory intensive that they would entirely consume the Sega CD memory capacity requiring the gamer to either delete their game saves or obtain a memory cart to allow them to play and save other games.  The memory carts were available from Sega and third party sources.
  • Some Sega CD games were compatible with and even a few were packaged with a light gun.  A number of such light gun capable games combined FMV with light gun use.  The light guns required were also compatible with similar Genesis cartridge based games.

Hooking Up The Sega CD

  • If you don’t have the original Sega CD manual, check out these scans from the manual: Flickr Photset / PDF Download
  • A MK1 Genesis to either Sega CD requires an audio mixing cable.  It goes from the headphone jack on the Genesis to the Mixing input on the back of the CD.  Output is (if you want stereo) audio from the CD from the CD’s RCA jacks and the video from the Genesis.
  • With a Mk2, no mixing cable is required, just get the audio from the CD and the video from the Genesis.
  • The mixer cable isn’t anything special.  It’s simply a mini-pin stereo cable, male plug on both ends.  You could get something that would work at Radio Shack for a few bucks.  The official Sega version has one of those noise reduder things molded into the cable, not sure how necessary it is.
  • If so desired, all audio (mono) and video can be gotten out of the RF output on the Genesis.
  • When the 32X is involved, there are no additional connections concerning the SCD, but the connections between the Genesis and 32X get more complicated.

Frequently Asked Questions

  • Can I play Sega Genesis / Megadrive ROMs on the Sega CD via a CD-R?  Nope.  You would most likely need an emulator of some sort and that hasn’t been developed. See here for more detail and discussion.
  • Can I use a Model 1 Genesis with a Model 2 Sega CD or a Model 2 Genesis with a Model 1 Sega CD?  You sure can.  In fact, for the longest time, I personally used a Model 2 Genesis with a Model 1 SCD as that’s the only SCD model my local Funcoland had.


Helliant1 says:

Anybody remember the LaserActive by Pioneer that had gaming console add-ons? Your options were Sega Genesis and/or TruboGrafx 16 and if I remember correctly, were both around the size of an internal cd drive of today. The exclusive games sold on LaserDisc, for the most part, were mostly existing games ported over with beautifully per-rendered backgrounds with non-synthesized, studio quality recorded music or soundtracks. Would like to know what that unit is selling for these days. I picked one up when I was around 18 and barely had any credit, got approved for the thing and returned it a month later. I needed to pay my car insurance and couldn’t pay my insurance and the credit cards bill, so I returned it. The laserdisc player alone was $1,000 and I think the Genesis adaptor was another $399, more or less, as a whole was very expensive!

racketboy says:

Yeah, that thing was epic. It’s one of those dream pieces of hardware. Although nowadays, you’d always be hoping the thing wouldn’t die on you. I think I mentioned it in the Genesis 101 guide. :). Pretty cool that you owned one for at least a little bit 😉

helliant1@icould.comant1 says:

Does anyone remember the Sega power strip you could buy for the Sega Genesis/CD setup? It’s nothing fancy or over the top any power strip would suffice. But, was made to accept the big power adapters as the plugins where spaced accordingly and between each outlet spelled out Sega like this example ⦿S⦿E⦿G⦿A⦿! If I could post a picture of it I would as I still use it today in my garage for whatever I need to plug in at my work bench.

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