Sega CD

The Sega CD is an add-on for the Megadrive/Genesis developed by Sega. It was released in 1991.

This system scrapes metadata for the segacd group(s) and loads the segacd set from the currently selected theme, if available.

MD5 checksum Share file path Description
e66fa1dc5820d254611fdcdba0662372 bios/bios_CD_E.bin
854b9150240a198070150e4566ae1290 bios/bios_CD_U.bin
278a9397d192149e84e820ac621a8edd bios/bios_CD_J.bin

Place your Sega CD ROMs in /userdata/roms/segacd.

RetroArch (formerly SSNES), is a ubiquitous frontend that can run multiple “cores”, which are essentially the emulators themselves. The most common cores use the libretro API, so that's why cores run in RetroArch in Batocera are referred to as “libretro: (core name)”. RetroArch aims to unify the feature set of all libretro cores and offer a universal, familiar interface independent of platform.

RetroArch configuration

RetroArch offers a Quick Menu accessed by pressing [HOTKEY] + South button (B SNES) which can be used to alter various things like RetroArch and core options, and controller mapping. Most RetroArch related settings can be altered from Batocera's EmulationStation.

Standardized features available to all libretro cores: segacd.videomode, segacd.ratio, segacd.smooth, segacd.shaders, segacd.pixel_perfect, segacd.decoration, segacd.game_translation

ES setting name batocera.conf_key Description ⇒ ES option key_value
Settings that apply to all cores of this emulator
GRAPHICS BACKEND segacd.gfxbackend Choose your graphics rendering
⇒ OpenGL opengl, Vulkan vulkan.
AUDIO LATENCY segacd.audio_latency Audio latency in milliseconds, turn it up if you hear crackles
⇒ 256 256, 192 192, 128 128, 64 64, 32 32, 16 16, 8 8.
THREADED VIDEO segacd.video_threaded Improves performance at the cost of latency and more video stuttering. Use only if full speed cannot be obtained otherwise.
⇒ On true, Off false.

libretro: Genesisplusgx

A good all-around emulator. It can run Sega Genesis/Megadrive, Sega Master System, Sega/Mega CD and Game Gear games, but lacks 32X and Pico support. It is also the only emulator to support Lock-On technology, but can only be activated in RetroArch's Quick Menu ( [HOTKEY] + South button (B SNES)) (correct as of v31). After resetting the game, Lock-On will be activated. By default, Batocera will reset this setting after exiting the game. This can be changed on a per-game basis by using RetroArch's Overrides. There are patches available for ROMs that set the flag to boot into their Lock-On ROMs instead, so this is not strictly required to play those games.

libretro: Genesisplusgx configuration
ES setting name batocera.conf_key Description ⇒ ES option key_value
Settings that apply to all systems this core supports
REDUCE SPRITE FLICKERING global.gpgx_no_sprite_limit The Megadrive/Genesis can only draw ~80 sprites per horizontal line at a time, and any more will be mitigated by rapidly flickering between them each frame. This setting removes that limitation. Some games rely on the limit to mask certain sprites, but is generally not noticeable when removed.
⇒ Off disabled, On enabled.
Settings specific to megadrive
NTSC FILTER megadrive.gpgx_blargg_filter_md GenesisPlusGX has the Blarg NTSC filter built-in as a feature, unrelated to the shader selected within Batocera. This applies only to Megadrive/Genesis games. Batocera's or RetroArch's preset shaders can be used instead.
⇒ Off False, Composite (color bleeding + artifacts) composite, SVideo (color bleeding only) svideo, RGB (crisp image) rgb.
SHOW LIGHTGUN CROSSHAIR megadrive.gun_cursor_md Shows crosshairs for Menacer and Justifiers devices. This applies only to Megadrive/Genesis games.
⇒ Off disabled, On enabled.
CONTROLLER 1 TYPE megadrive.controller1_md The Megadrive/Genesis has many types of peripherals, notably a 6-button controller that some games require to be fully functional and a few lightguns. This is also where you would set your multi-tap on, if required.
⇒ Joypad Auto 1, Joypad 3 Button 257, Joypad 6 Button 513, Joypad 3 Button + 4-WayPlay 1025, Joypad 6 Button + 4-WayPlay 1281, Joypad 3 Button + Teamplayer 1537, Joypad 6 Button + Teamplayer 1793, Mouse 2.
CONTROLLER 2 TYPE megadrive.controller2_md Same as above but also has the Menacer Light Gun and Konami Justifiers available.
⇒ Joypad Auto 1, Joypad 3 Button 257, Joypad 6 Button 513, Joypad 3 Button + 4-WayPlay 1025, Joypad 6 Button + 4-WayPlay 1281, Joypad 3 Button + Teamplayer 1537, Joypad 6 Button + Teamplayer 1793, Mouse 2, Menacer Light Gun 516, Konami Justifiers 772.
Settings specific to mastersystem
NTSC FILTER mastersystem.gpgx_blargg_filter_ms GenesisPlusGX has the Blarg NTSC filter built-in as a feature, unrelated to the shader selected within Batocera. This applies only to Master System games. Batocera's or RetroArch's preset shaders can be used instead.
⇒ Off False, Composite (color bleeding + artifacts) composite, SVideo (color bleeding only) svideo, RGB (crisp image) rgb.
FM CHIP (YM2413) mastersystem.ym2413 Enhanced sound output support for compatible games.
⇒ Autodetect automatic, Off disabled, On (forced) enabled.
SHOW LIGHTGUN CROSSHAIR mastersystem.gun_cursor_ms Shows crosshairs for Menacer and Justifiers devices. This applies only to Master System games.
⇒ Off disabled, On enabled.
CONTROLLER 1 TYPE mastersystem.controller1_ms Select 2 button controller, Lightgun or Multitap.
⇒ Joypad 2 Button 769, Joypad 2 Button + Master Tap 2049, Light Phaser 260, Paddle Control 261.
CONTROLLER 2 TYPE mastersystem.controller2_ms Select 2 button controller, Lightgun or Multitap.
⇒ Joypad 2 Button 769, Joypad 2 Button + Master Tap 2049, Light Phaser 260, Paddle Control 261.
Settings specific to gamegear
LCD GHOSTING FILTER gamegear.lcd_filter Simulate LCD ghosting effects.
⇒ Off disabled, On enabled.
EXTENDED SCREEN gamegear.gg_extra Extend the game screen area like on a Master System.
⇒ Off disabled, On enabled.

libretro: Picodrive

A lighter emulator which although not as accurate as GenesisPlusGX, can be run on much weaker hardware. This should be the default for devices such as the Raspberry Pi Zero and other sub-1GHz CPUs. Currently the only cross-architecture option for 32X and Pico games.

libretro: Picodrive configuration
ES setting name batocera.conf_key Description ⇒ ES option key_value
Settings that apply to all systems this core supports
REDUCE SPRITE FLICKERING gamegear.picodrive_sprlim The Megadrive can only draw ~80 sprites per horizontal line at a time, and any more will be mitigated by rapidly flickering between them each frame. This setting removes that limitation. Some games rely on the limit to mask certain sprites, but is generally not noticeable when removed.
⇒ Off disabled, On enabled.
CROP OVERSCAN gamegear.picodrive_cropoverscan Crops out video edge hidden under bezel of analog TV.
⇒ Off disabled, On enabled.
CONTROLLER 1 TYPE gamegear.picodrive_controller1 Select 3 or 6 button controller.
⇒ Joypad 3 Button 3 button pad, Joypad 6 Button 6 button pad.
CONTROLLER 2 TYPE gamegear.picodrive_controller2 Same as above, but for port 2.
⇒ Joypad 3 Button 3 button pad, Joypad 6 Button 6 button pad.

Here are the Sega CD's controls shown on a Batocera Retropad:

For further troubleshooting, refer to the generic support pages.

  • systems/segacd.txt
  • Last modified: 8 months ago
  • by atari