PC Engine SuperGrafx (Beetle SGX)Link

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Standalone port of Mednafen PCE Fast to libretro.

Why use this core?Link

Awaiting description.

How to get and install the Beetle SGX core:Link

  1. Start up RetroArch. Inside the main menu, go to 'Online Updater'.

  2. Just to make sure we have the latest info files, select 'Update Core Info FIles'. Wait until this is done. Then, select 'Core Updater'.

  3. Browse through the list and select 'PC Engine SuperGrafx (Beetle SGX)'.

After this has finished downloading, the core should now be ready for use!

How to start (after installation):Link

  1. Go back to RetroArch's main menu screen. Select 'Load Content'.

  2. Browse to the folder that contains the content you want to run.

  3. Select the content that you want to run.

  4. If you are asked which core to select, choose 'PC Engine SuperGrafx (Beetle SGX)'.

The content should now start running!


See alsoLink

NEC PC EngineLink


A summary of the licenses behind RetroArch and its cores have found here.



Content that can be loaded by the Beetle SGX core have the following file extensions:

  • .pce
  • .sgx
  • .cue
  • .ccd
  • .chd


RetroArch database(s) that are associated with the Beetle SGX core:


Required or optional firmware files go in RetroArch's system directory.

Any CD-ROM System BIOS will work, but some them are known to be incompatible with certain games.

Filename Description md5sum
syscard3.pce Super CD-ROM2 System V3.xx - Required 38179df8f4ac870017db21ebcbf53114
syscard2.pce CD-ROM System V2.xx - Optional
syscard1.pce CD-ROM System V1.xx - Optional
gexpress.pce Game Express CD Card - Optional


Which PCE CD BIOS file the Beetle SGX core will use can be configured by the 'CD BIOS' core option.


RetroArch-level settings or features that the Beetle SGX core respects.

Feature Supported
Core Options
RetroArch Cheats
Native Cheats
Disk Control
Crop Overscan


The Beetle SGX core's directory name is 'Mednafen SuperGrafx'

The Beetle SGX core saves/loads to/from these directories.

RetroArch's Save directory

  • 'content-name'.srm (Save)

RetroArch's State directory

  • 'content-name'.state# (State)

Geometry and timingLink

  • The Beetle SGX core's internal FPS is 59.82
  • The Beetle SGX core's internal sample rate is 44100 Hz
  • The Beetle SGX core's core provided aspect ratio is dependent on the 'Aspect Ratio' core option.

Loading PC Engine CD contentLink

To load PC Engine CD content, Beetle SGX needs a cue-sheet that points to an image file. A cue sheet, or cue file, is a metadata file which describes how the tracks of a CD or DVD are laid out.

If you have e.g. foo.bin, you should create a text file and save it as foo.cue. If you're playing a single-track Saturn game, then the cue file contents should look like this:


 FILE "foo.bin" BINARY
  TRACK 01 MODE1/2352
   INDEX 01 00:00:00

After that, you can load the foo.cue file in RetroArch with the Beetle SGX core.

Certain PC Engine content are multi-track, so their .cue files might be more complicated.

Core optionsLink

The Beetle SGX core has the following option(s) that can be tweaked from the core options menu. The default setting is bolded.

Settings with (Restart) means that core has to be closed for the new setting to be applied on next launch.

  • CD Image Cache (Restart) (Off/On)

    Loads the complete image in memory at startup. Can potentially decrease loading times at the cost of increased startup time.

  • CD Bios (Restart) (System Card 3/Games Express/System Card 1/System Card 2)

    Select which PC Engine CD BIOS to use.

  • Force SuperGrafx Emulation (Restart) (Off/On)

    This is helpful to run homebrew games or isolate games that will not run in SuperGrafx mode. (like Space Harrier).


Savestates are not compatible with each mode. It's better to leave this option at default (Off) unless needed. Known Supergrafx games (like Dai-Makaimura, Aldyns) will automatically switch to SuperGrafx regardless of this option.

  • No Sprite Limit (Restart) (Off/On)

    Remove 16-sprites-per-scanline hardware limit.

  • CPU Overclock Multiplier (Restart) (1/2/3/4/5/6/7/8/9/10/20/30/40/50)

    Overclock the emulated CPU.

  • Horizontal Overscan (352 Width Mode Only) (300 to 352 in increments of 2. 352 in default.)

    Awaiting description.

  • Initial scanline (0 to 40 in increments of 1. 3 is default.)

    Adjust first display scanline.

  • Last scanline (208 to 242 in increments of 1. 242 is default.)

    Adjust last display scanline.

  • (CD) CDDA Volume % (0 to 200 in increments of 10. 100 is default.)

    Awaiting description.

  • (CD) ADPCM Volume % (0 to 200 in increments of 10. 100 is default.)

    Awaiting description.

  • (CD) CD PSG Volume % (0 to 200 in increments of 10. 100 is default.)

    Awaiting description.

  • (CD) CD Speed (1/2/4/8)

    Set the speed of the emulated CD drive.

  • Turbo Delay (3/4/5/6/7/8/9/10/11/12/13/14/15/30/60/2)

    Awaiting description.

  • Turbo ON/OFF Toggle (Off/On)

    Enables Turbo ON/OFF inputs. Look at the Controllers table section for more information.

  • Alternate Turbo Hotkey (Off/On)

    Enables Alternate Turbo ON/OFF inputs. You can avoid remapping Button III and IV when switching to 6-button gamepad mode with this. Look at the Controllers table section for more information.

  • Mouse Sensitivity (1.00 to 5.00 in increments of 0.25. 1.00 is default.)

    Configure the Mouse device type's sensitivity.

  • Aspect Ratio (auto/6:5/4:3)

    Select an auto (PAR) aspect ratio, or a 6:5 (Used to be default) aspect ratio, or a 4:3 TV aspect ratio.


When using games that constantly switches between 256 and 352 modes and using auto aspect, its best to set Horizontal width to 342 as to minimize resizing and extra black lines since this width is in ratio of 256-width mode(or something like that, just test with Asuka 100% which is one of the game that switches between these modes)


Device typesLink

The Beetle SGX core supports the following device type(s) in the controls menu, bolded device types are the default for the specified user(s):

User 1 - 5 device typesLink

  • None - Input disabled.
  • PCE Joypad - Joypad
  • Mouse - Mouse

Controller tablesLink

Joypad and analog device type tableLink

User 1 - 5 Remap descriptors RetroPad Inputs PCE Joypad 2-button mode PCE Joypad 6-button mode
III II Turbo On/Off † III
Select Select Select
Run Run Run
D-Pad Up D-Pad Up D-Pad Up
D-Pad Down D-Pad Down D-Pad Down
D-Pad Left D-Pad Left D-Pad Left
D-Pad Right D-Pad Right D-Pad Right
IV I Turbo On/Off † IV
Mode Switch Mode Switch Mode Switch
Alternate II Turbo On/Off §
Alternate I Turbo On/Off §


Which PCE Joypad button mode is in use can be configured by the Mode Switch input.


The regular Turbo inputs for 2-button mode are only active when the 'Turbo ON/OFF Toggle' core option is set to On.



The Alternate Turbo inputs for 2-button mode are only active when the 'Turbo ON/OFF Toggle' core option is set to On and the 'Alternate Turbo Hotkey' core option is set to On.

Mouse device type tableLink

User 1 - 5 Remap descriptors RetroMouse Inputs Mouse
Mouse Cursor
Left Button
Right Button


Awaiting description.