Mednafen

PC-FX Documentation

Last updated January 2, 2024
Valid as of 1.32.0-UNSTABLE

Table of Contents:

Introduction


Firmware/BIOS

Place a correct BIOS image file in the correct location.

The filename listed below is per default pcfx.bios setting.

Filename:Purpose:SHA-256 Hash:
pcfx.romPC-FX BIOS version 1.00. Recommended BIOS version.4b44ccf5d84cc83daa2e6a2bee00fdafa14eb58bdf5859e96d8861a891675417

Default Key Assignments

Key(s):Action:Configuration String:
ALT + SHIFT + 1Activate in-game input configuration process for device on virtual input port 1.input_config1
ALT + SHIFT + 2Activate in-game input configuration process for device on virtual input port 2.input_config2

Key:Action/Button:
Keypad 4IV
Keypad 5V
Keypad 6VI
Keypad 1III
Keypad 2II
Keypad 3I
Keypad 8MODE 1
Keypad 9MODE 2
Enter/ReturnRun
TabSelect
WUp
SDown
ALeft
DRight

Settings Reference

Caution: Any settings that change emulation behavior as seen from the emulated game are shown with the setting name bolded in the table. One should be conscious of these settings if one has changed them from the default values when using network play or movies, as they can cause desychronizations if not set the same among hosts(or between the recording emulator and the playing emulator).

Setting:Value Type:Possible Values:Default Value:Description:
pcfx.adpcm.emulate_buggy_codecboolean0
1
0Hack that emulates the codec a buggy ADPCM encoder used for some games' ADPCM.
 
pcfx.adpcm.suppress_channel_reset_clicksboolean0
1
1Hack to suppress clicks caused by forced channel resets.
 
pcfx.biosstring pcfx.romPath to the ROM BIOS
 
pcfx.cdspeedinteger2 through 102Emulated CD-ROM speed.

Setting the value higher than 2, the default, will decrease loading times in most games by some degree.

 
pcfx.cpu_emulationenumfast
accurate
auto
autoCPU emulation mode.
  • fast - Fast Mode
    Fast mode trades timing accuracy, cache emulation, and executing from hardware registers and RAM not intended for code use for performance.

  • accurate - Accurate Mode
    Increased timing accuracy, though not perfect, along with cache emulation, at the cost of decreased performance. Additionally, even the pipeline isn't correctly and fully emulated in this mode.

  • auto - Auto Mode
    Selects "fast" or "accurate" automatically based on an internal database. If the CD image is not recognized, defaults to "fast".
 
pcfx.disable_bramboolean0
1
0Disable internal and external BRAM.

It is intended for viewing games' error screens that may be different from simple BRAM full and uninitialized BRAM error screens, though it can cause the game to crash outright.

 
pcfx.disable_softresetboolean0
1
0When RUN+SEL are pressed simultaneously, disable both buttons temporarily.
 
pcfx.fxscsistring 0Path to the FX-SCSI ROM

Intended for developers only.

 
pcfx.high_dotclock_widthenum256
341
1024
1024Emulated width for 7.16MHz dot-clock mode.

Lower values are faster, but will cause some degree of pixel distortion.

  • 256 - 256 pixels
    This value will cause heavy pixel distortion.

  • 341 - 341 pixels
    This value will cause moderate pixel distortion.

  • 1024 - 1024 pixels
    This value will cause no pixel distortion as long as interpolation is enabled on the video output device and the resolution is sufficiently high, but it will use a lot of CPU time.
 
pcfx.input.port1enumnone
gamepad
mouse
gamepadInput device for Port 1
  • none - none

  • gamepad - Gamepad

  • mouse - Mouse
 
pcfx.input.port1.multitapboolean0
1
0Enable multitap on PC-FX port 1.

EXPERIMENTAL emulation of the unreleased multitap. Enables ports 3 4 5.

 
pcfx.input.port2enumnone
gamepad
mouse
gamepadInput device for Port 2
  • none - none

  • gamepad - Gamepad

  • mouse - Mouse
 
pcfx.input.port2.multitapboolean0
1
0Enable multitap on PC-FX port 2.

EXPERIMENTAL emulation of the unreleased multitap. Enables ports 6 7 8.

 
pcfx.input.port3enumnone
gamepad
mouse
gamepadInput device for Port 3
  • none - none

  • gamepad - Gamepad

  • mouse - Mouse
 
pcfx.input.port4enumnone
gamepad
mouse
gamepadInput device for Port 4
  • none - none

  • gamepad - Gamepad

  • mouse - Mouse
 
pcfx.input.port5enumnone
gamepad
mouse
gamepadInput device for Port 5
  • none - none

  • gamepad - Gamepad

  • mouse - Mouse
 
pcfx.input.port6enumnone
gamepad
mouse
gamepadInput device for Port 6
  • none - none

  • gamepad - Gamepad

  • mouse - Mouse
 
pcfx.input.port7enumnone
gamepad
mouse
gamepadInput device for Port 7
  • none - none

  • gamepad - Gamepad

  • mouse - Mouse
 
pcfx.input.port8enumnone
gamepad
mouse
gamepadInput device for Port 8
  • none - none

  • gamepad - Gamepad

  • mouse - Mouse
 
pcfx.mouse_sensitivityreal through 1.25Mouse sensitivity.
 
pcfx.nospritelimitboolean0
1
0Remove 16-sprites-per-scanline hardware limit.
 
pcfx.rainbow.chromaipboolean0
1
0Enable bilinear interpolation on the chroma channel of RAINBOW YUV output.

This is an enhancement-related setting. Enabling it may cause graphical glitches with some games.

 
pcfx.resamp_qualityinteger0 through 53Sound quality.

Higher values correspond to better SNR and better preservation of higher frequencies("brightness"), at the cost of increased computational complexity and a negligible increase in latency.

 
pcfx.resamp_rate_errorreal0.0000001 through 0.00003500.0000009Output rate tolerance.

Lower values correspond to better matching of the output rate of the resampler to the actual desired output rate, at the expense of increased RAM usage and poorer CPU cache utilization.

 
pcfx.slendinteger0 through 239235Last rendered scanline.
 
pcfx.slstartinteger0 through 2394First rendered scanline.
 

Setting:Value Type:Possible Values:Default Value:Description:
pcfx.debugger.disfontsizeenum5x7
6x9
6x12
6x13
9x18
5x7Disassembly font size.

Note: Setting the font size to larger than the default may cause text overlap in the debugger.

  • 5x7 - 5x7

  • 6x9 - 6x9

  • 6x12 - 6x12

  • 6x13 - 6x13. CJK support.

  • 9x18 - 9x18; CJK support.
 
pcfx.debugger.memcharencstring shift_jisCharacter encoding for the debugger's memory editor.
 
pcfx.enableboolean0
1
1Enable (automatic) usage of this module.
 
pcfx.forcemonoboolean0
1
0Force monophonic sound output.
 
pcfx.scanlinesinteger-100 through 1000Enable scanlines with specified opacity.

Opacity is specified in %; IE a value of "100" will give entirely black scanlines.

Negative values are the same as positive values for non-interlaced video, but for interlaced video will cause the scanlines to be overlaid over the previous(if the "video.deinterlacer" setting is set to "weave", the default) field's lines.

 
pcfx.shaderenumnone
autoip
autoipsharper
scale2x
sabr
ipsharper
ipxnoty
ipynotx
ipxnotysharper
ipynotxsharper
goat
noneEnable specified OpenGL shader.

Obviously, this will only work with the OpenGL "video.driver" setting, and only on cards and OpenGL implementations that support shaders, otherwise you will get a black screen, or Mednafen may display an error message when starting up. When a shader is enabled, the "pcfx.videoip" setting is ignored.

  • none - None/Disabled

  • autoip - Auto Interpolation
    Will automatically interpolate on each axis if the corresponding effective scaling factor is not an integer.

  • autoipsharper - Sharper Auto Interpolation
    Same as "autoip", but when interpolation is done, it is done in a manner that will reduce blurriness if possible.

  • scale2x - Scale2x

  • sabr - SABR v3.0
    GPU-intensive.

  • ipsharper - Sharper bilinear interpolation.

  • ipxnoty - Linear interpolation on X axis only.

  • ipynotx - Linear interpolation on Y axis only.

  • ipxnotysharper - Sharper version of "ipxnoty".

  • ipynotxsharper - Sharper version of "ipynotx".

  • goat - Simple approximation of a color TV CRT look.
    Intended for fullscreen modes with a vertical resolution of around 1000 to 1500 pixels. Doesn't simulate halation and electron beam energy distribution nuances.
 
pcfx.shader.goat.fprogboolean0
1
0Force interlaced video to be treated as progressive.

When disabled, the default, the "video.deinterlacer" setting is effectively ignored with respect to what appears on the screen, unless it's set to "blend" or "blend_rg". When enabled, it may be prudent to disable the scanlines effect controlled by the "pcfx.shader.goat.slen" setting, or else the scanline effect may look objectionable.

 
pcfx.shader.goat.hdivreal-2.00 through 2.000.50Constant RGB horizontal divergence.
 
pcfx.shader.goat.patenumgoatron
borg
slenderman
goatronMask pattern.
  • goatron - Goatron
    Brightest.

  • borg - Borg
    Darkest.

  • slenderman - Slenderman
    Spookiest?
 
pcfx.shader.goat.slenboolean0
1
1Enable scanlines effect.
 
pcfx.shader.goat.tpreal0.00 through 1.000.50Transparency of otherwise-opaque mask areas.
 
pcfx.shader.goat.vdivreal-2.00 through 2.000.50Constant RGB vertical divergence.
 
pcfx.specialenumnone
hq2x
hq3x
hq4x
scale2x
scale3x
scale4x
2xsai
super2xsai
supereagle
nn2x
nn3x
nn4x
nny2x
nny3x
nny4x
noneEnable specified special video scaler.

The destination rectangle is NOT altered by this setting, so if you have xscale and yscale set to "2", and try to use a 3x scaling filter like hq3x, the image is not going to look that great. The nearest-neighbor scalers are intended for use with bilinear interpolation enabled, for a sharper image, though the "autoipsharper" shader may provide better results.

  • none - None/Disabled

  • hq2x - hq2x

  • hq3x - hq3x

  • hq4x - hq4x

  • scale2x - scale2x

  • scale3x - scale3x

  • scale4x - scale4x

  • 2xsai - 2xSaI

  • super2xsai - Super 2xSaI

  • supereagle - Super Eagle

  • nn2x - Nearest-neighbor 2x

  • nn3x - Nearest-neighbor 3x

  • nn4x - Nearest-neighbor 4x

  • nny2x - Nearest-neighbor 2x, y axis only

  • nny3x - Nearest-neighbor 3x, y axis only

  • nny4x - Nearest-neighbor 4x, y axis only
 
pcfx.stretchenum0
full
aspect
aspect_int
aspect_mult2
aspect_mult2Stretch to fill screen.
  • 0 - Disabled

  • full - Full
    Full-screen stretch, disregarding aspect ratio.

  • aspect - Aspect Preserve
    Full-screen stretch as far as the aspect ratio(in this sense, the equivalent xscalefs == yscalefs) can be maintained.

  • aspect_int - Aspect Preserve + Integer Scale
    Full-screen stretch, same as "aspect" except that the equivalent xscalefs and yscalefs are rounded down to the nearest integer.

  • aspect_mult2 - Aspect Preserve + Integer Multiple-of-2 Scale
    Full-screen stretch, same as "aspect_int", but rounds down to the nearest multiple of 2.
 
pcfx.tblurboolean0
1
0Enable video temporal blur(50/50 previous/current frame by default).
 
pcfx.tblur.accumboolean0
1
0Accumulate color data rather than discarding it.
 
pcfx.tblur.accum.amountreal0 through 10050Blur amount in accumulation mode, specified in percentage of accumulation buffer to mix with the current frame.
 
pcfx.videoipenum0
1
x
y
1Enable (bi)linear interpolation.
  • 0 - Disabled

  • 1 - Bilinear

  • x - Linear (X)
    Interpolation only on the X axis.

  • y - Linear (Y)
    Interpolation only on the Y axis.
 
pcfx.xresinteger0 through 655360Full-screen horizontal resolution.

A value of "0" will cause the current desktop horizontal resolution to be used.

 
pcfx.xscalereal0.01 through 2563.000000Scaling factor for the X axis in windowed mode.
 
pcfx.xscalefsreal0.01 through 2561.000000Scaling factor for the X axis in fullscreen mode.

For this setting to have any effect, the "pcfx.stretch" setting must be set to "0".

 
pcfx.yresinteger0 through 655360Full-screen vertical resolution.

A value of "0" will cause the current desktop vertical resolution to be used.

 
pcfx.yscalereal0.01 through 2563.000000Scaling factor for the Y axis in windowed mode.
 
pcfx.yscalefsreal0.01 through 2561.000000Scaling factor for the Y axis in fullscreen mode.

For this setting to have any effect, the "pcfx.stretch" setting must be set to "0".