Retro FAQ: Sega Megadrive / Sega Genesis

Discussion in 'Retro & Arcade' started by elvis, Nov 14, 2018.

  1. elvis

    elvis Old school old fool

    Joined:
    Jun 27, 2001
    Messages:
    36,647
    Location:
    Brisbane
    This is a partner series to our Retro Let's Play FAQ, aiming to assist people finding ways of playing old games from these old systems. All talk of resolutions, PAL vs NTSC and upscaling are covered in the Retro Display Solutions thread.

    With the roaring success of the 8 bit console market, and the collapse of arcades, the 16bit market powered by new chips and technology was just starting. While NEC and Hudson Soft had worked together to make their odd hybrid 8/16bit PC Engine (named the TurboGrafx in the US), Sega were the second to market with their MegaDrive console.

    Sporting the same Motorola 68000 CPU that powered the Amiga 1000, Sega took a distinctly Japanese approach to hardware design, and offered a powerful and extensible console system that greatly improved on their previous Master System as well as Nintendo's NES.

    The console, while rudimentary by today's design, was quite a stunning piece of hardware on release. It offered arcade-style graphics and sounds totally unavailable in the home, and would go on to offer not just arcade ports, but many exclusive games that would define the home console genre for some time.

    While Sega had found some success with the Master System outside of the US, their 8 bit console never found the success that the NES did in their core markets of Japan and the USA. The release of the Sega Genesis (renamed from the MegaDrive) in the US changed that dramatically, with partnerships with companies like EA who would create and dominate licensed sporting games for many years to come, which were massively popular in the US. Meanwhile the Japanese MegaDrive boomed with arcade style shoot 'em ups, platformers and expansive RPGs popular in that area.

    The MegaDrive cleverly used the Master System's main Z80 CPU as its IO controller, which meant that with a simple converter cartridge, most Master System cartridge (as well as SG1000 card) games could run perfectly on the MegaDrive. This offered nice backwards compatibility to anyone upgrading across the Sega line.

    Sega would go on to release several versions of the hardware, within them quite a number of hardware revisions. The smaller internal revisions are not so important for playing the games, but more for modders. But for the larger revisions, there was:

    MegaDrive - first version of the console, with the larger case. Mono sound only out of the rear of the device, with stereo sound available only through the headphone jack at the front.

    MegaDrive II: Smaller base unit than the first console. Due to some poor motherboard design, the sound and video quality is noticeably worse, even though the console finally offers stereo out via the main AV port.

    MegaDrive III: A smaller unit again, and again with compromised sound and video quality. Notable for missing RGB out all together.

    Sega would later offer a CD-ROM upgrade for their system, named the MegaCD (SegaCD in the USA), which offered not only CD storage and audio, but an updated chip that could do some rudimentary 3D. Another upgrade came years later in the form of the 32X, and odd system that contained a single SH2 processor (similar to the Saturn, albeit much slower in clockspeed, and not a dual-CPU setup), but still required the MegaDrive to run.

    Some odd third party combinations of the MegaDrive would appear over time, including the WonderMega (combined MegaDrive / MegaCD) and the Teradrive (combined MegaDrive / PC).


    PAL vs NTSC

    Like other 16 bit consoles of its era, the MegaDrive's release in PAL territories was capped at the PAL standard of 50Hz. Very few games were adjusted for the difference, and as the hardware clock was tied so closely to the frame output, NTSC games designed for 60Hz displays were slowed down.

    Likewise PAL's extra resolution of 288 lines meant that NTSC's 240 line pictures would appear "squashed" with black borders above and below the picture.

    While there were a handful of European designed games that played as intended, the vast majority of games for the PAL MegaDrive only play at full speed on a US or Japanese system, or a PAL system modified (see below).

    Here's the MegaDrive's "killer app", Sonic, running on both systems side by side. The visual speed difference is clear, and listen out for the music difference half way as the source is switched.



    Playing the original system today

    Original MegaDrives are still in good supply, and most can be bought easily on eBay.

    Later model revisions employ copy protection via Sega's "TMSS" chip (noticeable from the copyright screen that appears before the Sega logo at boot), but there are devices that can be bought to circumvent this, which we'll cover below.

    Japanese units are often quite cheap, and allow for simple modding to enable playing US or PAL games.

    As always, the MLIG crew are the first to hit up to find out the best way to get these systems playing, looking and sounding the best:



    Hardware modding

    The MegaDrive is quite mod-friendly, with plenty of third party hardware engineers offering all sorts of circuits to enhance it.

    Simpler mods include region switching:
    http://www.mmmonkey.co.uk/category/sega/megadrive/

    And more complex mods involve hijacking RGB and audio signals to remove picture and sound interference, and improve the audio in newer model hardware:
    https://voultar.com/index.php?route=product/product&path=59&product_id=73
    http://retrorgb.com/genesisrgbbypass.html

    All of these do require soldering, but are great options for people wanting to play on real hardware.

    Flash, reproduction and clone carts


    The popularity of the MegaDrive and Genesis worldwide has seen plenty of third party cartridges made for it.

    From excellent quality stuff like Krikzz's line of Everdrives:
    https://krikzz.com/store/home/33-mega-everdrive-v2.html

    To dodgy Chinese clone carts:
    https://www.aliexpress.com/wholesal...d=AS_20181113192437&SearchText=sega+megadrive

    Clone consoles (FPGA)

    FPGA gurus Analogue and retro engineer Kevtris teemed up to make the Analogue Mega Sg:
    https://forums.overclockers.com.au/threads/analogue-mega-sg.1254087/

    This FPGA-based console is a cycle accurate simulation of the original MegaDrive, takes original and/or clone cartridges, and is compatible with most controllers (not lightguns, for CRT/sync related reasons).

    The device offers an internal line-multiplier for lag-free upscaling up to 1080p, and HDMI out. Like the NES and SNES models, various filters and timing mode fixes are available to make for more authentic and/or more compatible experiences with modern TVs and hardware.

    [March 2018 update] The Analogue Mega Sg is out, and MLIG have an excellent summary:



    The MiSTer FPGA project also has a functioning Megadrive/Genesis core. See the OCAU thread here:
    https://forums.overclockers.com.au/...r-console-arcade-hardware-simulation.1253887/

    Clone consoles (non-FPGA)

    A number of clone consoles exist currently from the infamous AtGames. These are widely considered terrible, with poor quality emulation, awful graphics and audio, and input lag. So bad, in fact, I won't even bother linking to them.

    Sega themselves were very unhappy with these, and announced almost a year ago that they would design their own mini-console in-house. The release of this has been delayed, presumably to improve the quality. Fingers crossed Sega rectify the issue, and leave the AtGames devices in the dust.

    Emulation

    MegaDrive emulation has been around for quite some time, courtesy of the popularity of the M68K main CPU and Z80 CPU, both of which are used in many consoles and computers, and have had plenty of good quality documentation.

    Unlike more complex consoles like the SNES, MegaDrive emulation is typically more consistent, and easier to achieve even on lower end hardware.

    With that said, the "gold standard" emulator for the MegaDrive is "BlastEm", which is the only cycle-accurate emulator to pass the most stringent hardware tests:
    https://www.retrodev.com/blastem/

    Other less accurate, but still playable emulators are available.

    https://github.com/RetroPie/RetroPie-Setup/wiki/Mega-Drive-Genesis

    Good quality emulators such as "Genesis Plus" (available in RetroArch and RetroPie) are written by the same folks who contribute to MAME (in this case, Charles MacDonald). While emulators like PicoDrive aim to get comaptibility as high as possible while still being playable on low-end hardware (even on a NintendoDS!).
     
    Last edited: Apr 1, 2019
    hippyhippy and power like this.
  2. OP
    OP
    elvis

    elvis Old school old fool

    Joined:
    Jun 27, 2001
    Messages:
    36,647
    Location:
    Brisbane
    RetroCore has been around ages (pre-youtube!) making videos about life in Japan, and Megadrive gaming. Here's one of his earlier Megadrive videos:


    He also reviews some terrible Chinese knockoff megadrives and gives you a feel for their varying quality:




     
  3. hippyhippy

    hippyhippy Member

    Joined:
    Apr 1, 2004
    Messages:
    6,851
    Location:
    Sydney
    One of the best consoles ever I think... Pity i never owned 1 ... Owned energy other sega console though ...
     
  4. OP
    OP
    elvis

    elvis Old school old fool

    Joined:
    Jun 27, 2001
    Messages:
    36,647
    Location:
    Brisbane
    Terraonion have annouced their "Mega SD" - a full MegaCD / SegaCD ODE (Optical Drive Emulator), shaped as universal cartridge for any Megadrive/Genesis compatible console. They've shown it working in original Megadrive/Genesis consoles, as well as the Analogue Mega Sg and a genuine Sega Nomad.

    The device also works like a full Megadrive/Genesis flash cart, playing all original Megadrive/Genesis games, and offers Master System backwards compatibility if your console supports it. Other features include the ability to do streamed music, similar to the MSU-1 hacks on SNES.

    https://downloads.terraonion.com/public/MegaSD_press_release.pdf

    https://www.retrorgb.com/terraonion-mega-sd-worlds-first-sega-cd-ode.html

     
    Last edited: Jun 18, 2019
    Daft_Munt likes this.
  5. Grant

    Grant Member

    Joined:
    Jan 23, 2002
    Messages:
    1,300
    Location:
    Wollongong
    This is so cool - what I need is an ODE for the Mega CD though, I have a Model 1 with a busted drive mechanism that I may finish fixing one day.

    Still, it should now start to limit any outrageous price hikes for original hardware, and get Mega CD games running on a lot more CRTs - kudos to the developers :thumbup:
     
  6. OP
    OP
    elvis

    elvis Old school old fool

    Joined:
    Jun 27, 2001
    Messages:
    36,647
    Location:
    Brisbane
    Unlikely. Even with all these advancements in ODEs, flashcarts, FPGA consoles and whatnot, prices are still insane.

    So be it. I'm happy there are good quality devices that offer an experience close enough to original hardware even for purists to enjoy. The state of retro gaming was a little worrying for a while (emulation is great, but lag was always a worry), but devices like ODEs and FPGA consoles are making that far less of an issue these days.
     
  7. bolex17

    bolex17 Member

    Joined:
    Feb 11, 2004
    Messages:
    1,148
    Location:
    Adelaide, 5010
    Thanks for the writeup elvis, never had a Megadrive growing up so I still have so much to catch up on!
    Still deciding on what Everdrive to get.. not sure if I should splurge and get the X7 over the X5
     
    Last edited: Jul 5, 2019
    elvis likes this.
  8. power

    power Member

    Joined:
    Apr 20, 2002
    Messages:
    58,459
    Location:
    brisbane
    anyone going to order a MEGA SD?

    these things look awesome.

    The PAL vs NTSC thing still does my head in we were completely oblivious back in the day so it wasn't an issue.
     
  9. OP
    OP
    elvis

    elvis Old school old fool

    Joined:
    Jun 27, 2001
    Messages:
    36,647
    Location:
    Brisbane
    Considering it, but MiSTer is currently doing an amazing job of satisfying all my needs. No MegaCD support yet, but it (and PC Engine CDROM) are being worked on.

    Import gamers knew about it. Certainly all the bigger UK magazines I followed as a kid (CVG, Mean Machines [both of these had excellent writers who now work for Digital Foundry, RetroGamerMag, etc], etc) all covered the issue and made people aware of it.

    You could instantly tell from the borders. Our aspect ratios here in Australia were totally different to US magazine screenshots. That was a massive give-away that something was up.

    I think it was pretty obvious to the technically minded.
     
  10. power

    power Member

    Joined:
    Apr 20, 2002
    Messages:
    58,459
    Location:
    brisbane
    I was a kid, weeee shiny things. Had nfi at the time :D

    having said that i installed a PAL/NTSC switch in my Amiga, pretty much because I thought I'd get more games and a fuller screen.

    I think it enabled a couple of demos or something.
     
    Last edited: Jul 5, 2019
  11. OP
    OP
    elvis

    elvis Old school old fool

    Joined:
    Jun 27, 2001
    Messages:
    36,647
    Location:
    Brisbane
    I was also a kid. One who pulled apart everything electronic he could get his hands on, played with every bit of AV equipment he could find, programmed every computer he could touch.

    Technology was huge and amazing and I wanted to know everything I could about anything that used electrons, photons or anything else tiny and magic for interesting purposes. Curiosity was, and still is, the biggest thing for me. In an infinite universe of stuff, we know so little. Get learning while the learning's good, I say.

    See? You knew about it. :)
     
    Last edited: Jul 5, 2019
  12. Camm

    Camm Member

    Joined:
    Oct 1, 2010
    Messages:
    860
    Almost pulled the trigger on the terraonion device, but honestly, I want to see a top load fpga also support 32x before I do, especially for $400 or so AUD.

    And can I just say I fucking hate the Mega Drive for hardware revisions. Model 1's are generally great, but require modding for stereo, and some have jailbars, model 2's require modding to fix everything, model 3's are garbage, and wondermega's are over $1k.

    Add on that accessory fit between 1,2,3 and WM's all vary, and its enough to drive someone to drink.
     
  13. OP
    OP
    elvis

    elvis Old school old fool

    Joined:
    Jun 27, 2001
    Messages:
    36,647
    Location:
    Brisbane
    More videos on the MegaSD from the regular round of trusted YouTubers:





    And longer SmkeMonster streams showing it off:



     
    power likes this.
  14. power

    power Member

    Joined:
    Apr 20, 2002
    Messages:
    58,459
    Location:
    brisbane
    the best thing about the Mega SD is it makes the tower even taller, but not as tall as Sonic lock on carts :D
     
    elvis likes this.
  15. bolex17

    bolex17 Member

    Joined:
    Feb 11, 2004
    Messages:
    1,148
    Location:
    Adelaide, 5010
    Got my Mega Everdrive X5 and 8bitdo wireless pad
    [​IMG]

    Had a play with it last night and I can definitely see why you guys reccomend I upgrade to the Mega AMP....
    That said I now have a triple bypass board on order.
     
    Grant and elvis like this.

Share This Page

Advertisement: