Visual Memory Unit

Visual Memory Unit
Made for: Sega Dreamcast
Manufacturer: Sega
Type: Memory card
Release Date RRP Code JP 1998-11-27 ¥2,500 (2,625)2,500e US 1999-09-09 EU 1999-10-14 DE 1999 DM 59.9559.95 PL 2000-12-01 150zł150 AU 1999 $49.9549.95 BR xxxx

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Visual Memory Unit (VMU), referred to as the Visual Memory(ビジュアルメモリ) or VM (and VMS) in Japan is the de facto "memory card" for the Sega Dreamcast. While its most basic function is as a removable storage device, the VMU can also serve as an auxiliary display during normal gameplay and, through the use of additional software, it can act as a console independent of the Dreamcast.

Hardware

The introduction of the VMU was considered quite radical in 1998, for as well as being a means of storing Dreamcast data, it acts as its own independent handheld "console", capitalising on a craze started by Bandai with its Tamagotchi device in late 1996. When plugged into a Dreamcast controller it can act as an extra screen, but if removed it becomes a system with its own D-Pad, ,  MODE  and SLEEP buttons.

In order to function on its own, a VMU requires two CR2032 batteries, which can lead to problems. It does not require batteries in order to function within a Dreamcast controller (when the controller is connected and the system is powered on), but if the VMU lacks power it will make a high pitched warning screech during the console's bootup to alert the user.

Two VMUs can be connected together (another idea copied from Bandai, this time in its 1997 Digital Monster range, opening up new possibilities such as transferring data or playing two-player games.

Like the controllers and console, there are many different flavours of VMU in terms of colours. The colours vary depending on the market - in Japan there were many novelty VMUs, often inspired by games. In North America, translucent coloured VMUs were released, while in Europe very few coloured VMUs were sold.

The VMU technically debuted four months before the Dreamcast console, with the release of the Atsumete Godzilla: Kaijuu Dai Shuugou VMU in July 1998. As well as being a self-contained game in itself, it can be treated as a Dreamcast memory card.

Criticism

While the VMU is considered an integral part of the Dreamcast console, the built-in screen and its arguably superfluous features led to a high price point when compared to memory cards of the PlayStation and Nintendo 64. Furthermore, initial shipments of Dreamcast consoles did not come with VMUs, and as the Dreamcast has no built-in memory (unlike the Sega Saturn), an extra purchase was required to save games (and comparitively few games were offering alternatives such as passwords than had been the case earlier in the decade).

Despite the higher price, capacity is comparable to the original PlayStation, with both claiming to have 1Mb (128kB) of storage data. Sega did not offer an official non-screened memory card until December 2000, when the 4x Memory Card was released in Japan. The "4x" in this instance symbolises the 512kB of data available to users, though as each 128kB chunk is treated as a separate card by the console, it is much the same as purchasing four separate VMUs.

With the PlayStation, Sony opted to divide its memory cards into 15 blocks (thought to be around 64kB of memory each). The majority of PlayStation games use a single block to save (regardless of whether the full 64kB is used), and while some games are known to use as many as four blocks, their scarcity means PlayStation memory cards are almost guaranteed to house save data for 10-15 titles. With the Dreamcast, no such guarantee was in place - while 200 blocks (about 512 byes each) are available, no rules were put in place to stop developers from filling a memory card with the save data of just one game.

The widely publicised "VMU games" also take up save blocks. Anyone wanting to play, for example, Chao Adventure, a free VMU download in Dreamcast launch title Sonic Adventure, will need to reserve 128 blocks of memory just for this game. Users often find themselves needing reserve a VMU specifically for this purpose, as while in this the 72 remaining memory blocks could still be used for smaller titles, larger games like Shenmue require more than 72 blocks to save (Shenmue needs 80).

In addition, some save games cannot be transferred between VMUs (indicated with a red border in the Dreamcast's file manager), and as with the PlayStation, VMUs in anything other than the first port of the first controller may not be detected by software (although this practise is far less common than on Sony's machine). Rune Jade is notorious for its VMU usage, demanding 198 blocks of memory, despite, in most cases, not using all of it.

The 200 block limit is also artifically restricted, with Sega reserving memory for VMU system functionality, most of it going unused. Third-party tools have since been developed to reformat VMUs to tap into some of this unused memory, creating a further 44 blocks in the process without degrading system performance. However, some games (such as Metropolis Street Racer) will not recognise this extra memory, and third-party memory cards are not guaranteed to be expandable in the same way.

Unlike modern consoles, VMUs lack lithium-ion rechargable batteries (seen in the Game Boy Advance SP and newer), and so their batteries need to be replaced manually on a fairly regular basis. When a Dreamcast system is turned off, no signal is sent to the VMUs to shut down, and so operate on their own power source for a short period of time before automatically switching themselves off. If left unchecked, this can cause VMUs to drain power just by being plugged into a Dreamcast console (although the internal clock means VMUs always lose power when batteries are inserted).

With four controllers and eight powerless VMUs plugged in, each will screech in unison when the system is turned on. No settings exist in either the VMU or Dreamcast BIOS to prevent this (although third-party cards without speakers are unaffected), and can be offputting for users unaware of this feature.

Like many handhelds of the era, the VMU does not have a backlit (or frontlit) screen, and so is difficult to see in low-light conditions. Hardware modifications can be made to circumvent this, however no official solution was ever offered (or even discussed) while the Dreamcast console was on sale.

Technical specifications

47 mm (1.85")

80 mm (3.15")

16 mm (0.63")

• CPU: Sanyo LC86K87 (8-bit CPU, energy saving)
• Memory: 128 KB (200 blocks)
• Power source: Two CR2032 batteries with auto-off function
• Display: 48 dot Width x 32 dot Height resolution, Monochrome
• Display size: 37 mm (1.46 inches) Width x 26 mm (1.02 inches) Height
• Sound: PWM sound chip, 1-channel PWM sound source
• Mass: 45g (0.099 pounds)

Compatibility

Incompatible games

By the time the Dreamcast launched, saving games on console was well established across the gaming industry, meaning it was widely expected that any Dreamcast game would be compatible with the Visual Memory Unit (this is in contrast to the Sega Saturn, where although an internal memory saving option was available, many games were still built around a password system).

As such, unlike other Dreamcast accessories, it is more useful to list games that are not compatible with the VMU (and by extension, any Dreamcast memory card). Demos aside, the number of games which utilise a memory card is quite small and only applies to certain genres (South Park: Chef's Luv Shack for example is a multiplayer quiz game so has nothing worthwhile to "save").

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History

Legacy

While few Dreamcast games made full use of the Visual Memory Unit, its design and many of the concepts it pioneered would be adopted by several future video games consoles. It has also received aftermarket software support from dedicated fans.

In Japan, Sony began marketing a similar product for its PlayStation line, the PocketStation, as early as January 1999, and while the device was not sold outside its home country, it is thought that nearly five million units were sold before it was discontinued. PocketStation memory functions can only be accessed when plugged into a PlayStation, however dozens of PocketStation games could be downloaded from PlayStation discs. Connectivity between Sony handheld consoles would later be explored with the PlayStation Portable and PlayStation Vita.

Nintendo is generally associated with pushing the idea of a secondary screen, starting with the "Game Link Cable", which allows a Game Boy Advance to be connected to a Nintendo GameCube, first seen in 2001. The concept was revisited, albeit with greater emphasis on the dual screen idea, with the Wii U console in 2012, with ideas being brought over to its successor, the Nintendo Switch in 2017.

Smartphones, which saw a rise in adoption during the late 2000s, have also been used by video games as secondary screens, however without direct connections, most are relegated to displaying static content, often similar in nature to how many Dreamcast games utilise the VMU when plugged into a controller.

Versions

Japan

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Code	Name	Box scans	Images	Region	Date	Price	Documentation	Description
HKT-7001	Atsumete Godzilla: Kaijuu Dai Shuugou あつめてゴジラ〜怪獣大集合〜			JP	1998-07-30	¥2,5002,500
HKT-7002	Visual Memory ビジュアルメモリ			JP	1998-11-27	¥2,500 (2,625)2,500 (2,625)
HKT-7005	Mothra Dream Battle モスラドリームバトル			JP	1998-12-23			HKT-7002 (with software) and figurine
HKT-7006	Gamera Dream Battle ガメラドリームバトル			JP	1999-03-25			HKT-7002 (with software) and figurine
HKT-7007-03	Visual Memory Colour Version (Aqua Blue) ビジュアルメモリ･カラーバージョン (アクアブルー)			JP	2000-03-01 ?	¥2,500 (2,625)2,500 (2,625)
HKT-7007-04	Visual Memory Colour Version (Lime Green) ビジュアルメモリ･カラーバージョン (ライムグリーン)			JP	2000-03-01 ?	¥2,500 (2,625)2,500 (2,625)
HKT-7007-05	Visual Memory Colour Version (Passion Pink) ビジュアルメモリ･カラーバージョン (パッションピンク)			JP	2000-03-01 ?	¥2,500 (2,625)2,500 (2,625)
HKT-7007-06	Visual Memory Colour Version (Smoke) ビジュアルメモリ･カラーバージョン (スモーク)			JP	2000-03-01 ?	¥2,500 (2,625)2,500 (2,625)
HKT-7007-16	Visual Memory Clear ビジュアルメモリ クリア			JP	2000-12-01 ?	¥2,500 (2,625)2,500 (2,625)
HKT-7007-17	Virtual Memory Sonic Team version ビジュアルメモリ ソニックチームバージョン			JP	2000-12-21 ?
HKT-7007-18	SGGG (Segagaga) Virtual Memory SGGG (セガガガ) ビジュアルメモリ			JP	2001-03-29			See also Segagaga
HKT-7008-01	Super Inventor Boy Kanipan Playing Kid DCDC 超発明BOYカニパン あそんでキッドDCDC(デシデシ)			JP	1999-04-22
HKT-7008-02	Giant Channel ジャイアントチャネル			JP	1999-05-20
HKT-7009-01	Visual Memory US Blue ビジュアルメモリ USレッド			JP	2001-11-01 ?	¥2,500 (2,625)2,500 (2,625)
HKT-7009-02	Visual Memory US Red ビジュアルメモリ USブルー			JP	2001-11-01 ?	¥2,500 (2,625)2,500 (2,625)
DD	Visual Memory: Pearl White ビジュアルメモリ：パールホワイト			JP	2000-08-31	¥2,8002,800
DD	Visual Memory: Pearl Blue ビジュアルメモリ：パールブルー			JP	2000-08-31	¥2,8002,800
DD	Visual Memory: Pearl Pink ビジュアルメモリ：パールピンク			JP	2000-08-31	¥2,8002,800
DD	Visual Memory: Pure Black ビジュアルメモリ：ピュアブラック			JP	2000-12-21	¥2,8002,800
DD	Visual Memory Clear Red ビジュアルメモリ クリアレッド			JP	2000-11-30			Site: Announcement. Christmas Lottery (30-11~20-12) Might be the same as HKT-7009-02.
DD	Visual Memory Capcom version ビジュアルメモリ カプコンバージョン			JP	2000-12-22	¥2,8002,800
DPB	Visual Memory: Camouflage ビジュアルメモリ：迷彩色			JP	1999-03-01 ?	¥2000 DPB points2000 DPB points
DPB	Visual Memory: Carbon Black ビジュアルメモリ：カーボンブラック			JP	1999-03-01 ?	¥2000 DPB points2000 DPB points
DPB	Visual Memory: Wood Grain ビジュアルメモリ：木目調			JP	2000-09-01	¥2000 DPB points2000 DPB points
DPB	Visual Memory: Leopard ビジュアルメモリ：豹柄			JP	2000-09-01	¥2000 DPB points2000 DPB points
DPB	Visual Memory: Marble ビジュアルメモリ：大理石調			JP	2000-09-01	¥2000 DPB points2000 DPB points
DPB	Visual Memory: Strawberry version ビジュアルメモリ：イチゴバージョン			JP	2001-05-17 ?	¥2000 DPB points2000 DPB points
DPB	Visual Memory: Dolphin version ビジュアルメモリ：イルカバージョン			JP	2001-05-17 ?	¥2000 DPB points2000 DPB points
DPB	Visual Memory: Number version ビジュアルメモリ：ナンバーバージョン			JP	2001-05-17 ?	¥2000 DPB points2000 DPB points
	HDR-0089 bundle			JP	2000-05-25	PACK-INpack
	HDR-0148 bundle			JP	2001-03-22	PACK-INpack
	T-46301M bundle			JP	2001-09-06	PACK-INpack
	Seaman ~Forbidden Pet~ ?? シーマン～禁断のペット～ 同梱			JP	1999-07-29	PACK-INpack
	Hello Kitty Dreamcast Set (Blue Skeleton) bundle Hello Kitty ドリームキャストセット (スケルトンブルー) 同梱			JP	1999-11-25	PACK-INpack		Site: [1]
	Hello Kitty Dreamcast Set (Pink Skeleton) bundle Hello Kitty ドリームキャストセット (スケルトンピンク) 同梱			JP	1999-11-25	PACK-INpack		Site: [2]
	Dreamcast model: Seaman Christmas package bundle ドリームキャスト model:SEAMAN クリスマスパッケージ 同梱			JP	1999-12-19	PACK-INpack
	Dreamcast CODE: Veronica LIMITEDBOX bundle Dreamcast CODE: Veronica LIMITEDBOX 同梱		50x50px	JP	2000-02-03	PACK-INpack		Site: Announcement
	Dreamcast Sakura Taisen model bundle ドリームキャスト サクラ大戦モデル 同梱			JP	2000-12-01	PACK-INpack		Site: [3]
	Sakura Wars Contest VM			JP

US

The U.S. standard VM is undistinguisable from the Japanese counterpart. However, the colour series has slightly darker casing and has grey (instead of white) buttons (notice the starking difference between the Dreamcast inscription and the button colours). The US red and US blue Japanese VMs described above are a domestic release of their overseas versions, sporting the U.S. grey buttons and are only distinct by their different packaging.

Code	Name	Box scans	Images	Region	Date	Price	Documentation	Description
MK-50120	Visual Memory Unit			US
MK-50121	Visual Memory Unit (clear blue)
MK-50122	Visual Memory Unit (clear green)							A similar (or same) is included with the Holiday Gift Pack.
MK-50123	Visual Memory Unit (clear red)							A similar (or same) is included with the Holiday Gift Pack
MK-50124	Visual Memory Unit (clear yellow)
MK-50124	Visual Memory Unit (clear yellow)
MK-50125	Visual Memory Unit (clear black)

Europe

The standard PAL VM is different from the Japanese and U.S. devices as it does not have a spiral next to the Dreamcast inscription, and the inscription itself is made in a larger font.

Code	Name	Box scans	Images	Region	Date	Price	Documentation	Description
MK-55120	Visual Memory			EU

Magazine articles

Main article: Visual Memory Unit/Magazine articles.

Promotional material

Print advert in Next Level (AR) #11: "Diciembre 1999" (1999-xx-xx)

Print advert in Alaab Alcomputtar (SA) #16 (1999-02-xx)

Gallery

Official photographs

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Patents

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  USD410500

Physical scans

Sega Retro Average
Publication Score Source Computer & Video Games (UK) 100

	100
Based on 1 review

Sega Retro Average
Publication Version Score Computer & Video Games (UK) 100

	100
Based on 1 review

Visual Memory Unit

Dreamcast, US
Manual

Dreamcast, BR
Cover
Manual

Technical information

Reading save data

When reading save data from the memory manager on the Sega Dreamcast BIOS, it will appear in this format.

Save Data

Name	File Name	Comment	File Size
Name of the file.	Name of the file as it appears within the system.	Additional Information of File.	Number of Blocks Used.

How each file is named and what the comments field represents depends on how the developer has written each descriptor. When reading other articles on Sonic Retro and Sega Retro, keep in mind these common symbols represented in the wiki to determine the text as these variables are likely to differ when viewing on the Memory Manager.

[##] - Number

[MM] - Month

[DD] - Day