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VMU
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<h2 id="hardware">Hardware</h2> <p>For use as a memory card and second screen, the VMU is plugged directly into one of two slots on a Dreamcast controller (up to two VMUs may be plugged in each controller, and eight VMUs per Dreamcast console). </p><p>Upon initial use, the player is prompted to set the date and time, and then select from a group of bitmap images to serve as the default background for the VMU (various Dreamcast titles may offer players additional background images for the unit). This image is displayed while the Dreamcast console is in the operating system menu. </p><p>When operated independently of the Dreamcast console, the VMU acts as a file manager, clock/calendar (with selectable clock animations), and handheld game console. VMUs may also connect to each other directly to facilitate file transfer or <a href="/facts/Multiplayer_gaming/JNzato20">multiplayer gaming</a>. </p><p>The VMU runs on two <a href="/facts/CR2032_battery/fUaN3p0X">CR-2032</a> <a href="/facts/Lithium_battery/D5yfo8XS">lithium batteries</a> which are inserted into the rear of the VMU under a screw-secured lid. Without battery power, the VMU still functions as a memory card and auxiliary display, but cannot play downloaded mini-games. Additionally, a VMU without battery power will beep when the Dreamcast is powered on (if the VMU is inserted into a connected Dreamcast controller) </p><p>The VMU has 128 <a href="/facts/Kilobyte/jIe6t4yv">KB</a> of flash memory, but by default 28 KB is reserved for system use leaving 100 KB for data storage, which is divided into 200 'blocks' – one block equaling 512 bytes. In recent years, homebrew programs like Dream Explorer (aka VMU Tool) have allowed users to unlock an extra 44 blocks (22 KB) of this reserved space<a class="footnote-ref" id="fnref:2" href="#fn:2"><sup>2</sup></a> increasing the overall VMU capacity to 244 blocks. However, a handful of games might be unable to detect the memory card if this is done, although none have been reported apart from DreamKey/DreamPassport and <a href="/facts/Metropolis_Street_Racer/Vum36DRC">Metropolis Street Racer</a>. </p> <h2 id="minigames-and-in-game-features">Minigames and in-game features</h2> <p>Several titles for the Dreamcast include mini-games that can be downloaded onto a VMU. The <i><a href="/facts/Sonic_Adventure/Vg96Hz20">Sonic Adventure</a></i> series, for instance, include the <i>Chao Adventure</i> mini-games (<i>Chao Adventure</i> and <i>Chao Adventure 2</i> which features more activities and items). In the games, players can transfer <a href="/facts/Chao_(Sonic_the_Hedgehog)/deQoaI2f">Chao</a> eggs to the VMU and partake in various activities to increase the stats of their hatched Chao, whereupon they can upload their improved Chao back into the Dreamcast game. <i><a href="/facts/Sega_GT/ssc8L3Ll">Sega GT</a></i> includes <i>Pocket GT</i>, a top-down racer in the style of the 8-bit <i><a href="/facts/SpyHunter/JF0Vz7ac">SpyHunter</a></i> games. </p><p>In other video games, statistics such as the current health condition are displayed on the VMU for convenience (as in <i><a href="/facts/Resident_Evil%3a_Code_Veronica/AvS7sLNP">Resident Evil: Code Veronica</a></i>) or to enhance multi-player gaming (for example, <i><a href="/facts/NFL_2K2/HRpQIvW1">NFL 2K2</a></i> allowed the VMU to display secret plays not viewable to other players). </p><p>There are also numerous homebrew games, original creations and ports of famous games that are freely available on the <a href="/facts/Internet/Xw1rVvJU">internet</a> and can be installed and played on a VMU. These games include: <i><a href="/facts/Metroid/PPUh26WA">Metroid</a></i>, <i><a href="http://www.deco.franken.de/myfiles/pacman.html">VMU Mini Pacman</a></i>, <i><a href="/facts/Breakout_(video_game)/4G7LJqCF">Breakout</a></i>, <i><a href="/facts/Space_Invaders/A4R9djwo">Space Invaders</a></i>, <i><a href="/facts/Tetris/djLfTK0n">Tetris</a></i>, <i>VMU Fighter</i> (a side-scrolling shoot 'em up), <i>VMU Football</i> (an American football game), <i>VMU-a-Sketch</i> (a digital Etch-a-sketch pad), and <i>3D FPS</i> (a first-person-shooter).<a class="footnote-ref" id="fnref:3" href="#fn:3"><sup>3</sup></a> </p> <table><tbody><tr><th>Dreamcast game</th><th>VMU minigame</th><th>In-game features</th></tr><tr><td><i><a href="/facts/Cardcaptor_Sakura/eq3Sx6M3">Cardcaptor Sakura: Tomoyo no Video Daisakusen</a></i></td><td>Three mini-games:<ul><li>Breakout</li><li>Oyatu</li><li>Tobakero</li></ul><p>Clock (four themes)</p></td><td>?</td></tr><tr><td><i><a href="/facts/Carrier_(video_game)/tphNQfHb">Carrier</a></i></td><td>—</td><td>Health condition</td></tr><tr><td><i><a href="/facts/D2_(video_game)/DtMCcque">D2</a></i></td><td>Photo viewer</td><td>Compass</td></tr><tr><td><i><a href="/facts/Dino_Crisis_(video_game)/P7JTUKNA">Dino Crisis</a></i></td><td>—</td><td><ul><li>Health condition</li><li>Ammo count</li></ul></td></tr><tr><td><i><a href="/facts/Evil_Twin%3a_Cyprien%2527s_Chronicles/TBfo572U">Evil Twin: Cyprien's Chronicles</a></i></td><td>Four mini-games (downloadable)</td><td>?</td></tr><tr><td><i><a href="/facts/Evolution%3a_The_World_of_Sacred_Device/bPuMl359">Evolution: The World of Sacred Device</a></i></td><td>?</td><td>Health condition</td></tr><tr><td><i><a href="/facts/Evolution_2%3a_Far_Off_Promise/9NAmAXGP">Evolution 2: Far Off Promise</a></i></td><td>12-hour clock</td><td>—</td></tr><tr><td><i><a href="/facts/F355_Challenge/B0XfREt1">F355 Challenge</a></i></td><td>—</td><td>Arcade connectivity</td></tr><tr><td><i><a href="/facts/Godzilla_Generations/tvHxJ25m">Godzilla Generations</a></i> (Japanese version)</td><td>Three mini-games:<ul><li>Atsumete Godzilla</li><li>Gamera Dream Battle</li><li>Mothra Dream Battle</li></ul></td><td>?</td></tr><tr><td><a href="/facts/Jet_Set_Radio/ngSX089J"><i>Jet Set Radio</i> / <i>Jet Grind Radio</i></a></td><td>Graffiti transfer</td><td>—</td></tr><tr><td><i><a href="/facts/Marvel_vs._Capcom_2%3a_New_Age_of_Heroes/6K0hEV0h">Marvel vs. Capcom 2: New Age of Heroes</a></i></td><td>Transfer characters, colors and stages</td><td>Arcade connectivity</td></tr><tr><td><i><a href="/facts/Namco_Museum/y1gFdJyY">Namco Museum</a></i></td><td><i>Pac-It</i></td><td>—</td></tr><tr><td><i><a href="/facts/NBA_2K/qRgHJ6LR">NBA 2K</a></i> / <i><a href="/facts/NBA_2K1/Dlkx31Yq">2K1</a></i> / <i><a href="/facts/NBA_2K2/tB1hT2aI">2K2</a></i></td><td>—</td><td>Team statistics</td></tr><tr><td><i><a href="/facts/NFL_2K/GfD4lUsB">NFL 2K</a></i> / <i><a href="/facts/NFL_2K1/on4LdMjA">2K1</a></i> / <i><a href="/facts/NFL_2K2/HRpQIvW1">2K2</a></i> / <i><a href="/facts/NFL_Blitz/ANj9DrEc">Blitz</a></i></td><td>?</td><td>Secret plays</td></tr><tr><td><i><a href="/facts/Pen_Pen_TriIcelon/N9HzY6kA">Pen Pen TriIcelon</a></i></td><td>—</td><td>Currently selected playable character</td></tr><tr><td><i><a href="/facts/Pop%2527n_Music/DD9MP0bL">Pop'n Music</a></i> series</td><td><i>Pop'n Music Anywhere</i> mini-game</td><td>Virtual <i>Pop'n Music</i> controller</td></tr><tr><td><i><a href="/facts/Power_Stone_(video_game)/pxEIxUIy">Power Stone</a></i></td><td>Three mini-games:<ul><li><i>Gunrock’s Gun-Gun Slot</i></li><li><i>Falcon’s Aerial Adventure</i></li><li><i>Ayame’s Shuriken Training</i></li></ul></td><td>?</td></tr><tr><td><i><a href="/facts/Power_Stone_2/TvJfUcj0">Power Stone 2</a></i></td><td>View and trade items</td><td>?</td></tr><tr><td><i><a href="/facts/Quake_III_Arena/7WgcvDVt">Quake III Arena</a></i></td><td>Maze mini-game</td><td>Animation</td></tr><tr><td><i><a href="/facts/Ready_2_Rumble/z0BP2BSv">Ready 2 Rumble</a></i></td><td>?</td><td><ul><li>Punch count</li><li>Hit percentage</li></ul></td></tr><tr><td><i><a href="/facts/Resident_Evil/FpwRBJUs">Resident Evil</a></i> series</td><td>?</td><td>Health condition</td></tr><tr><td><i><a href="/facts/Sakura_Wars/nzPkE0Tp">Sakura Wars</a></i> 3</td><td>?</td><td><ul><li>Kinematron messages</li><li>Area map</li></ul></td></tr><tr><td><i><a href="/facts/Seaman_(video_game)/BbojYlQ6">Seaman</a></i></td><td>Organize and raise food for Seaman</td><td>Seaman <a href="/facts/Dreamcast_accessories/jdPb5uBX">microphone</a> status</td></tr><tr><td><i><a href="/facts/Sega_GT/ssc8L3Ll">Sega GT</a></i></td><td><i>Pocket GT</i> (Japan, Europe and US)</td><td>—</td></tr><tr><td><i><a href="/facts/Sega_Rally_2/le37rUsG">Sega Rally 2</a></i></td><td>Stats and records</td><td>—</td></tr><tr><td><i><a href="/facts/Shenmue_(video_game)/37JHxNmy">Shenmue</a></i></td><td><i>Shenmue Goodies</i></td><td>Training instructions</td></tr><tr><td><i><a href="/facts/Silent_Scope_(video_game)/7Bj1L7EW">Silent Scope</a></i></td><td>?</td><td>Sniper rifle scope view</td></tr><tr><td><i><a href="/facts/Skies_of_Arcadia/3haRJLss">Skies of Arcadia</a></i></td><td><i>Pinta's Quest</i></td><td>Cham alert</td></tr><tr><td><i><a href="/facts/Sonic_Adventure/Vg96Hz20">Sonic Adventure</a></i></td><td><i>Chao Adventure</i></td><td>Chao animation</td></tr><tr><td><i><a href="/facts/Sonic_Adventure_2/cISjsAqB">Sonic Adventure 2</a></i></td><td><i>Chao Adventure 2</i></td><td>—</td></tr><tr><td><i><a href="/facts/Sonic_Shuffle/TM2qrKRH">Sonic Shuffle</a></i></td><td>—</td><td>Revealed card numbers</td></tr><tr><td><i><a href="/facts/Soulcalibur_(video_game)/t4AvmDg1">Soulcalibur</a></i> (Japanese version)</td><td>Three mini-games</td><td>Animated characters</td></tr><tr><td><i><a href="/facts/Super_Magnetic_Neo/E2nIFsr5">Super Magnetic Neo</a></i></td><td>—</td><td>Secret area alerts</td></tr><tr><td><i><a href="/facts/Tech_Romancer/SE7JL3LF">Tech Romancer</a></i></td><td>Three mini-games</td><td>?</td></tr><tr><td><i><a href="/facts/Time_Stalkers/GCLnbXhz">Time Stalkers</a></i></td><td>Five mini-games</td><td>—</td></tr><tr><td><i>Tokyo Bus Guide</i></td><td><i>Traffic Signs Quiz</i></td><td>?</td></tr><tr><td><i><a href="/facts/TrickStyle/W56qQy2W">TrickStyle</a></i></td><td><i><a href="/facts/Snake_(video_game_genre)/HrVSdS1p">TrickStyle Jr.</a></i></td><td>?</td></tr><tr><td><i><a href="/facts/Virtua_Tennis_(video_game)/Jfq7IAx1">Virtua Tennis</a></i></td><td>?</td><td>Wireframe match</td></tr><tr><td><i><a href="/facts/Zombie_Revenge/oywk0SQ4">Zombie Revenge</a></i></td><td>Three mini-games</td><td>?</td></tr></tbody></table> <h2 id="variants">Variants</h2> <p>Multiple Dreamcast memory cards with no VMU features have been released. The cards therefore omit a display screen, input buttons, speaker and built-in clock. Some have the same 128 KB storage as the VMU, equivalent to 200 blocks, while others have multiple "pages" with each acting as a 128 KB memory card. In the latter case, a button or switch allows the user to select the desired memory card. This is due to the Dreamcast having a limit of 128 KB per individual memory card. </p> <h3>4x Memory Card</h3> <p>Sega released an official 4x Memory Card which offered four times the data storage of a standard VMU, with 800 blocks. It was released in Japan on December 14, 2000,<a class="footnote-ref" id="fnref:4" href="#fn:4"><sup>4</sup></a> as "Memory Card 4X", and in the US as "4x Memory Card". A button is used to select one of four "pages", and a series of four orange LED on the card indicates which of these is currently in use. Not all games are compatible, so Sega released a list of incompatible games.<a class="footnote-ref" id="fnref:5" href="#fn:5"><sup>5</sup></a> </p><p>A limited edition <i><a href="/facts/Phantasy_Star_Online/I34BHDbf">Phantasy Star Online</a></i> 4x Memory Card was also released in Japan to coincide with the game's release. It was coloured blue and featured the <i>Phantasy Star Online</i> logo printed onto the casing.<a class="footnote-ref" id="fnref:6" href="#fn:6"><sup>6</sup></a> </p><p>The 4x Memory Card did not make it to retail in Europe, despite a planned release (along with the <a href="/facts/Dreamcast_Broadband_Adapter/u0pzmNSs">Dreamcast Broadband Adapter</a> which was also unreleased in Europe) due to the Dreamcast's unforeseeably short lifespan – although unofficial third party 4x Memory Cards were released in Europe. </p> <h3>Third-party memory cards</h3> <p>The Nexus Memory Card is a third party version of the Visual Memory Unit that features four times the memory of a stock VMU with 800 blocks (4 <a href="/facts/Megabit/tR6WBEG3">megabit</a> / 512 <a href="/facts/Kilobytes/jIe6t4yv">kilobytes</a>) but lacks an LCD screen. The card is divided into 4 pages each with 200 blocks, each page can be selected using a button on the top left of the card.<a class="footnote-ref" id="fnref:7" href="#fn:7"><sup>7</sup></a> The Nexus Memory Card is slightly larger than the normal VMU and can be connected to a <a href="/facts/Personal_computer/koaYfNce">personal computer</a> by <a href="/facts/USB/XcIKWLyg">USB</a>, <a href="/facts/D-subminiature/ygqtB3CQ">Parallel</a> or <a href="/facts/D-subminiature/ygqtB3CQ">Serial</a> cable. A 3200 block (16 <a href="/facts/Megabit/tR6WBEG3">megabit</a> / 2 <a href="/facts/Megabytes/RBF4XpWb">megabytes</a>) version of the Nexus is also available, but this model has been known to be unstable. </p><p><a href="/facts/Nyko/EgPyRQkj">Nyko</a> released two memory cards for the Dreamcast: the Jumbo Memory Pak X2 with twice the storage as a VMU, and the Hyperpak with four times the storage. The Hyperpak could also act as a Jump Pak by setting its switch to rumble mode. </p><p>The Performance Memory Card was a third-party basic memory card with the same 200 blocks of storage as a VMU. The Performance Mega Memory Card acted like a 4X Memory Card. It used a switch on its back to select the desired memory card "page". Unlike other memory cards however, the Performance model had to be removed from the controller before the "page" could be switched. </p><p>In September 2023, following a successful <a href="/facts/Crowdfunding_in_video_games/TjjvJoWt">crowdfunding</a> campaign, Dreamware Enterprises released an aftermarket VMU update called the VM2. The VM2 features a backlit screen, a rechargeable battery with <a href="/facts/USB-C/7qVuop6e">USB-C</a> support, and <a href="/facts/MicroSD/RLL9UTly">MicroSD</a> storage.<a class="footnote-ref" id="fnref:8" href="#fn:8"><sup>8</sup></a> </p> <h2 id="reception">Reception</h2> <p>In a 10-year retrospective, <a href="/facts/GamesRadar/K8hRVA8R">GamesRadar</a> called the VMU "one of our favorite storage devices". They offered praise for the originality of the device, as well its flexibility and commented that newer systems should have revisited the concept. However, they lamented that most games didn't find a useful purpose for it and that the device drained batteries quickly.<a class="footnote-ref" id="fnref:9" href="#fn:9"><sup>9</sup></a> In 2024, <i><a href="/facts/Time_Extension/SW2goULD">Time Extension</a></i> called the VMU "an important evolution of the memory card concept".<a class="footnote-ref" id="fnref:10" href="#fn:10"><sup>10</sup></a> </p> <h2 id="see-also">See also</h2> <ul><li><a href="/facts/PocketStation/7Qna66dY">PocketStation</a>, a similar device by Sony for the PlayStation, released six months later.</li></ul> <h2 id="external-links">External links</h2> <ul><li><a href="https://web.archive.org/web/20110714050713/http://rvmu.maushammer.com/faq.html">The (Unofficial) VMU FAQ (Wayback Machine)</a></li></ul> <h2 id="references">References</h2> <ol> <li id="fn:1"><p>"Dreamcast Visual Memory Card VMS/VMU (Godzilla Design)". Play-Asia. Retrieved October 5, 2014. <a href="https://www.play-asia.com/dreamcast-visual-memory-card-vmsvmu-godzilla-design-paOS-13-49-en-70-5wz.html" target="_blank">https://www.play-asia.com/dreamcast-visual-memory-card-vmsvmu-godzilla-design-paOS-13-49-en-70-5wz.html</a> <a href="#fnref:1" class="footnote-back-ref">↩</a></p></li> <li id="fn:2"><p>"Dream Explorer". Archived from the original on October 7, 2011. Retrieved May 31, 2009. <a href="https://web.archive.org/web/20111007145443/http://bswirl.kitsunet.org/vmutool/release/about/?lg=en&menu=" target="_blank">https://web.archive.org/web/20111007145443/http://bswirl.kitsunet.org/vmutool/release/about/?lg=en&menu=</a> <a href="#fnref:2" class="footnote-back-ref">↩</a></p></li> <li id="fn:3"><p>"VMU Wonders". The Dreamcast Junkyard. Retrieved October 6, 2014. <a href="http://www.thedreamcastjunkyard.co.uk/2006/05/vmu-wonders.html" target="_blank">http://www.thedreamcastjunkyard.co.uk/2006/05/vmu-wonders.html</a> <a href="#fnref:3" class="footnote-back-ref">↩</a></p></li> <li id="fn:4"><p>"Dreamcast Memory Card 4X Details". Retrieved June 7, 2009. <a href="http://www.gamespot.com/news/2642229.html" target="_blank">http://www.gamespot.com/news/2642229.html</a> <a href="#fnref:4" class="footnote-back-ref">↩</a></p></li> <li id="fn:5"><p>"DC Memory Card 4X Compatibility List". Retrieved June 7, 2009. <a href="http://www.gamespot.com/news/2646823.html" target="_blank">http://www.gamespot.com/news/2646823.html</a> <a href="#fnref:5" class="footnote-back-ref">↩</a></p></li> <li id="fn:6"><p>"Dreamcast Memory Card 4X Details". Retrieved June 7, 2009. <a href="http://www.gamespot.com/news/2642229.html" target="_blank">http://www.gamespot.com/news/2642229.html</a> <a href="#fnref:6" class="footnote-back-ref">↩</a></p></li> <li id="fn:7"><p>"Review: 4X Nexus Memory Card w/PC Link". Retrieved May 31, 2009. <a href="http://www.segatech.com/technical/nexus/index.html" target="_blank">http://www.segatech.com/technical/nexus/index.html</a> <a href="#fnref:7" class="footnote-back-ref">↩</a></p></li> <li id="fn:8"><p>"Sega Dreamcast's iconic memory card is making a (Fundraised) comeback". September 21, 2022. <a href="https://www.theverge.com/2022/9/21/23365268/sega-dreamcast-vmu-virtual-memory-unit-card-2022-fundraiser-indiegogo-console" target="_blank">https://www.theverge.com/2022/9/21/23365268/sega-dreamcast-vmu-virtual-memory-unit-card-2022-fundraiser-indiegogo-console</a> <a href="#fnref:8" class="footnote-back-ref">↩</a></p></li> <li id="fn:9"><p>Wide, Tyler (September 8, 2009). "A tribute to the Dreamcast VMU". GamesRadar. Retrieved October 11, 2012. <a href="http://www.gamesradar.com/a-tribute-to-the-dreamcast-vmu/" target="_blank">http://www.gamesradar.com/a-tribute-to-the-dreamcast-vmu/</a> <a href="#fnref:9" class="footnote-back-ref">↩</a></p></li> <li id="fn:10"><p>McFerran, Damien (January 25, 2024). "In Memory Of Memory Cards". Time Extension. Hookshot Media. Retrieved January 30, 2024. <a href="https://www.timeextension.com/features/in-memory-of-memory-cards" target="_blank">https://www.timeextension.com/features/in-memory-of-memory-cards</a> <a href="#fnref:10" class="footnote-back-ref">↩</a></p></li> </ol>