<html> <head> <title>Mednafen Sega Genesis/MegaDrive Documentation</title> <link rel="stylesheet" type="text/css" media="screen, projection" href="mednafen.css" /> </head> <body> <center><h1><img alt="Mednafen" src="mednafen.png" width="696" height="204" /></h1></center> <center><h1>Sega Genesis/MegaDrive Documentation</h1></center> <center><i>Last updated August 11, 2011<br />Valid as of 0.9.18-WIP</i></center> <p> <b>Table of Contents:</b> <ul><li /><a href="#Introduction">Introduction</a><ul></ul><li /><a href="#Settings+Reference">Settings Reference</a><ul></ul></ul></p><hr width="100%" /> <a name="Introduction"><h2>Introduction</h2></a><p>Mednafen's Sega Genesis/Megadrive emulation is based off of <a href="http://cgfm2.emuviews.com/">Genesis Plus</a> and information and code from <a href="http://code.google.com/p/genplus-gx/">Genesis Plus GX</a>. The GPL-incompatible CPU and sound emulation cores in the aforementioned projects have been replaced with GPLed or GPL-compatible alternatives. <p> Sega Genesis/Megadrive emulation should still be considered experimental; there are still likely subtle bugs in the 68K emulation code, the YM2612 emulation code is not particularly accurate especially regarding features like SSG-EG, and the VDP code has timing-related issues. </p> <p> Sega 32X and Sega CD are not currently supported, though there is a bit of stub Sega CD code present currently. </p> </p><hr width="100%"> <a name="Settings+Reference"><h2>Settings Reference</h2></a><p><p> <b>Caution:</b> 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). </p> <p><table border><tr class="TableHeader"><th>Setting:</th><th>Value Type:</th><th>Possible Values:</th><th>Default Value:</th><th>Description:</th></tr><tr class="RowA"><td class="ColA"><a name="md.cdbios"><b>md.cdbios</b></a></td><td class="ColB">string</td><td class="ColC"> </td><td class="ColD">us_scd1_9210.bin</td><td class="ColE">Path to the CD BIOS<p>SegaCD/MegaCD emulation is currently nonfunctional.</p></td></tr><tr><td class="RowSpacer" colspan="5"> </td></tr> <tr class="RowB"><td class="ColA"><a name="md.correct_aspect">md.correct_aspect</a></td><td class="ColB">boolean</td><td class="ColC">0<br>1</td><td class="ColD">1</td><td class="ColE">Correct the aspect ratio.<p></p></td></tr><tr><td class="RowSpacer" colspan="5"> </td></tr> <tr class="RowA"><td class="ColA"><a name="md.input.port1"><b>md.input.port1</b></a></td><td class="ColB">enum</td><td class="ColC">none<br />gamepad2<br />gamepad<br />gamepad6<br />megamouse</td><td class="ColD">gamepad</td><td class="ColE">Input device for Port 1<p></p><ul><li><b>none</b> - none<br></li><br /><li><b>gamepad2</b> - 2-Button Gamepad<br></li><br /><li><b>gamepad</b> - 3-Button Gamepad<br></li><br /><li><b>gamepad6</b> - 6-Button Gamepad<br></li><br /><li><b>megamouse</b> - Sega Mega Mouse<br></li></ul></td></tr><tr><td class="RowSpacer" colspan="5"> </td></tr> <tr class="RowB"><td class="ColA"><a name="md.input.port2"><b>md.input.port2</b></a></td><td class="ColB">enum</td><td class="ColC">none<br />gamepad2<br />gamepad<br />gamepad6<br />megamouse</td><td class="ColD">gamepad</td><td class="ColE">Input device for Port 2<p></p><ul><li><b>none</b> - none<br></li><br /><li><b>gamepad2</b> - 2-Button Gamepad<br></li><br /><li><b>gamepad</b> - 3-Button Gamepad<br></li><br /><li><b>gamepad6</b> - 6-Button Gamepad<br></li><br /><li><b>megamouse</b> - Sega Mega Mouse<br></li></ul></td></tr><tr><td class="RowSpacer" colspan="5"> </td></tr> <tr class="RowA"><td class="ColA"><a name="md.region"><b>md.region</b></a></td><td class="ColB">enum</td><td class="ColC">game<br />overseas_ntsc<br />overseas_pal<br />domestic_ntsc<br />domestic_pal</td><td class="ColD">game</td><td class="ColE">Emulate the specified region's Genesis/MegaDrive<p></p><ul><li><b>game</b> - Match game's header.<br>Emulate the region that the game indicates it expects to run in via data in the header(or in an internal database for a few games that may have bad header data).</li><br /><li><b>overseas_ntsc</b> - Overseas(non-Japan), NTSC<br>Region used in North America.</li><br /><li><b>overseas_pal</b> - Overseas(non-Japan), PAL<br>Region used in Europe.</li><br /><li><b>domestic_ntsc</b> - Domestic(Japan), NTSC<br>Region used in Japan.</li><br /><li><b>domestic_pal</b> - Domestic(Japan), PAL<br>Probably an invalid region, but available for testing purposes anyway.</li></ul></td></tr><tr><td class="RowSpacer" colspan="5"> </td></tr> <tr class="RowB"><td class="ColA"><a name="md.reported_region"><b>md.reported_region</b></a></td><td class="ColB">enum</td><td class="ColC">same<br />game<br />overseas_ntsc<br />overseas_pal<br />domestic_ntsc<br />domestic_pal</td><td class="ColD">same</td><td class="ColE">Region reported to the game.<p></p><ul><li><b>same</b> - Match the region emulated.<br></li><br /><li><b>game</b> - Match game's header.<br>This option, in conjunction with the "md.region" setting, can be used to run all games at NTSC speeds, or all games at PAL speeds.</li><br /><li><b>overseas_ntsc</b> - Overseas(non-Japan), NTSC<br>Region used in North America.</li><br /><li><b>overseas_pal</b> - Overseas(non-Japan), PAL<br>Region used in Europe.</li><br /><li><b>domestic_ntsc</b> - Domestic(Japan), NTSC<br>Region used in Japan.</li><br /><li><b>domestic_pal</b> - Domestic(Japan), PAL<br>Probably an invalid region, but available for testing purposes anyway.</li></ul></td></tr><tr><td class="RowSpacer" colspan="5"> </td></tr> </table></p><p><table border><tr class="TableHeader"><th>Setting:</th><th>Value Type:</th><th>Possible Values:</th><th>Default Value:</th><th>Description:</th></tr><tr class="RowA"><td class="ColA"><a name="md.debugger.disfontsize">md.debugger.disfontsize</a></td><td class="ColB">enum</td><td class="ColC"></td><td class="ColD">small</td><td class="ColE">Disassembly font size.<p></p><ul></ul></td></tr><tr><td class="RowSpacer" colspan="5"> </td></tr> <tr class="RowB"><td class="ColA"><a name="md.debugger.memcharenc">md.debugger.memcharenc</a></td><td class="ColB">string</td><td class="ColC"> </td><td class="ColD">shift_jis</td><td class="ColE">Character encoding for the debugger's memory editor.<p></p></td></tr><tr><td class="RowSpacer" colspan="5"> </td></tr> <tr class="RowA"><td class="ColA"><a name="md.enable">md.enable</a></td><td class="ColB">boolean</td><td class="ColC">0<br>1</td><td class="ColD">1</td><td class="ColE">Enable (automatic) usage of this module.<p></p></td></tr><tr><td class="RowSpacer" colspan="5"> </td></tr> <tr class="RowB"><td class="ColA"><a name="md.forcemono">md.forcemono</a></td><td class="ColB">boolean</td><td class="ColC">0<br>1</td><td class="ColD">0</td><td class="ColE">Force monophonic sound output.<p></p></td></tr><tr><td class="RowSpacer" colspan="5"> </td></tr> <tr class="RowA"><td class="ColA"><a name="md.pixshader">md.pixshader</a></td><td class="ColB">enum</td><td class="ColC">none<br />ipxnoty<br />ipynotx<br />ipsharper<br />ipxnotysharper<br />ipynotxsharper<br />scale2x</td><td class="ColD">none</td><td class="ColE">Enable specified OpenGL pixel shader.<p>Obviously, this will only work with the OpenGL "video.driver" setting, and only on cards and OpenGL implementations that support pixel shaders, otherwise you will get a black screen, or Mednafen may display an error message when starting up. Bilinear interpolation is disabled with pixel shaders, and any interpolation, if present, will be noted in the description of each pixel shader.</p><ul><li><b>none</b> - None/Disabled<br></li><br /><li><b>ipxnoty</b> - Linear interpolation on X axis only.<br></li><br /><li><b>ipynotx</b> - Linear interpolation on Y axis only.<br></li><br /><li><b>ipsharper</b> - Sharper bilinear interpolation.<br></li><br /><li><b>ipxnotysharper</b> - Sharper version of "ipxnoty".<br></li><br /><li><b>ipynotxsharper</b> - Sharper version of "ipynotx".<br></li><br /><li><b>scale2x</b> - Scale2x<br></li></ul></td></tr><tr><td class="RowSpacer" colspan="5"> </td></tr> <tr class="RowB"><td class="ColA"><a name="md.scanlines">md.scanlines</a></td><td class="ColB">integer</td><td class="ColC">0 <i>through</i> 100</td><td class="ColD">0</td><td class="ColE">Enable scanlines with specified opacity.<p>Opacity is specified in %; IE a value of "100" will give entirely black scanlines.</p></td></tr><tr><td class="RowSpacer" colspan="5"> </td></tr> <tr class="RowA"><td class="ColA"><a name="md.special">md.special</a></td><td class="ColB">enum</td><td class="ColC">none<br />hq2x<br />hq3x<br />hq4x<br />scale2x<br />scale3x<br />scale4x<br />2xsai<br />super2xsai<br />supereagle<br />nn2x<br />nn3x<br />nn4x<br />nny2x<br />nny3x<br />nny4x</td><td class="ColD">none</td><td class="ColE">Enable specified special video scaler.<p>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, at high resolutions(such as 1280x1024; nn2x(or nny2x) + bilinear interpolation + fullscreen stretching at this resolution looks quite nice).</p><ul><li><b>none</b> - None/Disabled<br></li><br /><li><b>hq2x</b> - hq2x<br></li><br /><li><b>hq3x</b> - hq3x<br></li><br /><li><b>hq4x</b> - hq4x<br></li><br /><li><b>scale2x</b> - scale2x<br></li><br /><li><b>scale3x</b> - scale3x<br></li><br /><li><b>scale4x</b> - scale4x<br></li><br /><li><b>2xsai</b> - 2xSaI<br></li><br /><li><b>super2xsai</b> - Super 2xSaI<br></li><br /><li><b>supereagle</b> - Super Eagle<br></li><br /><li><b>nn2x</b> - Nearest-neighbor 2x<br></li><br /><li><b>nn3x</b> - Nearest-neighbor 3x<br></li><br /><li><b>nn4x</b> - Nearest-neighbor 4x<br></li><br /><li><b>nny2x</b> - Nearest-neighbor 2x, y axis only<br></li><br /><li><b>nny3x</b> - Nearest-neighbor 3x, y axis only<br></li><br /><li><b>nny4x</b> - Nearest-neighbor 4x, y axis only<br></li></ul></td></tr><tr><td class="RowSpacer" colspan="5"> </td></tr> <tr class="RowB"><td class="ColA"><a name="md.stretch">md.stretch</a></td><td class="ColB">enum</td><td class="ColC">0<br />full<br />aspect</td><td class="ColD">0</td><td class="ColE">Stretch to fill screen.<p></p><ul><li><b>0</b> - Disabled<br></li><br /><li><b>full</b> - Full<br>Full-screen stretch, disregarding aspect ratio.</li><br /><li><b>aspect</b> - Aspect Preserve<br>Full-screen stretch as far as the aspect ratio(in this sense, the equivalent xscalefs == yscalefs) can be maintained.</li></ul></td></tr><tr><td class="RowSpacer" colspan="5"> </td></tr> <tr class="RowA"><td class="ColA"><a name="md.tblur">md.tblur</a></td><td class="ColB">boolean</td><td class="ColC">0<br>1</td><td class="ColD">0</td><td class="ColE">Enable video temporal blur(50/50 previous/current frame by default).<p></p></td></tr><tr><td class="RowSpacer" colspan="5"> </td></tr> <tr class="RowB"><td class="ColA"><a name="md.tblur.accum">md.tblur.accum</a></td><td class="ColB">boolean</td><td class="ColC">0<br>1</td><td class="ColD">0</td><td class="ColE">Accumulate color data rather than discarding it.<p></p></td></tr><tr><td class="RowSpacer" colspan="5"> </td></tr> <tr class="RowA"><td class="ColA"><a name="md.tblur.accum.amount">md.tblur.accum.amount</a></td><td class="ColB">real</td><td class="ColC">0 <i>through</i> 100</td><td class="ColD">50</td><td class="ColE">Blur amount in accumulation mode, specified in percentage of accumulation buffer to mix with the current frame.<p></p></td></tr><tr><td class="RowSpacer" colspan="5"> </td></tr> <tr class="RowB"><td class="ColA"><a name="md.videoip">md.videoip</a></td><td class="ColB">boolean</td><td class="ColC">0<br>1</td><td class="ColD">1</td><td class="ColE">Enable bilinear interpolation.<p></p></td></tr><tr><td class="RowSpacer" colspan="5"> </td></tr> <tr class="RowA"><td class="ColA"><a name="md.xres">md.xres</a></td><td class="ColB">integer</td><td class="ColC">64 <i>through</i> 65536</td><td class="ColD">1024</td><td class="ColE">Full-screen horizontal resolution.<p></p></td></tr><tr><td class="RowSpacer" colspan="5"> </td></tr> <tr class="RowB"><td class="ColA"><a name="md.xscale">md.xscale</a></td><td class="ColB">real</td><td class="ColC">0.01 <i>through</i> 256</td><td class="ColD">3.000000</td><td class="ColE">Scaling factor for the X axis.<p></p></td></tr><tr><td class="RowSpacer" colspan="5"> </td></tr> <tr class="RowA"><td class="ColA"><a name="md.xscalefs">md.xscalefs</a></td><td class="ColB">real</td><td class="ColC">0.01 <i>through</i> 256</td><td class="ColD">3.200000</td><td class="ColE">Scaling factor for the X axis in fullscreen mode.<p></p></td></tr><tr><td class="RowSpacer" colspan="5"> </td></tr> <tr class="RowB"><td class="ColA"><a name="md.yres">md.yres</a></td><td class="ColB">integer</td><td class="ColC">64 <i>through</i> 65536</td><td class="ColD">768</td><td class="ColE">Full-screen vertical resolution.<p></p></td></tr><tr><td class="RowSpacer" colspan="5"> </td></tr> <tr class="RowA"><td class="ColA"><a name="md.yscale">md.yscale</a></td><td class="ColB">real</td><td class="ColC">0.01 <i>through</i> 256</td><td class="ColD">3.000000</td><td class="ColE">Scaling factor for the Y axis.<p></p></td></tr><tr><td class="RowSpacer" colspan="5"> </td></tr> <tr class="RowB"><td class="ColA"><a name="md.yscalefs">md.yscalefs</a></td><td class="ColB">real</td><td class="ColC">0.01 <i>through</i> 256</td><td class="ColD">3.200000</td><td class="ColE">Scaling factor for the Y axis in fullscreen mode.<p></p></td></tr><tr><td class="RowSpacer" colspan="5"> </td></tr> </table></p></p><hr width="100%"> </body> </html>
