Visual Memory Unit

From Sega Retro

Sega Dreamcast Visual Memory Unit

The VMU (short for Visual Memory Unit, not Virtual Memory Unit), also referred to as the Visual Memory System or VMS in Japan, is the "memory card" for the Sega Dreamcast. While its most basic function is as a removable storage device, the VMU has other purposes as well. It can 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.

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 hte 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. Furthermore, when the system is turned off, the VMUs are not, and so operate on their own power source for a short period of time before automatically switching themselves off. This means that the VMU will run out of batteries quicker if plugged in.

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.

Technical Specifications

  • CPU: 8-bit
  • Memory: 128 KB (200 blocks)
  • Power source: Two CR2032 batteries with auto-off function implemented in later versions of the VMU
  • Display: 48 dot Width x 32 dot Height, Monochrome
  • Display size: 37 mm (1.46 inches) Width x 26 mm (1.02 inches) Height
  • Case dimensions: 47 mm (1.85 inches) Width x 80 mm (3.15 inches) Height x 16 *mm (0.63 inches) Depth
  • Sound: 1-channel PWM sound source
  • Weight: 45g (0.099 pounds)

Gallery

Physical Scans


Sega Dreamcast
Topics Technical specifications (Hardware comparison) | History (Development | Release | Decline and legacy | Internet) | List of games | Magazine articles | Promotional material | Merchandise
Hardware Japan (Special) | Western Europe | Eastern Europe | North America | Asia | South America | Australasia | Africa
Add-ons Dreamcast Karaoke | Dreameye
Controllers Controller | Arcade Stick | Fishing Controller | Gun (Dream Blaster) | Race Controller | Maracas Controller (Third-party) | Twin Stick | Keyboard | Mouse | Third-party
Controller Add-ons Jump Pack (Third-party) | Microphone | VMU (4x Memory Card | Third-party)
Development Hardware Dev.Box | Controller Box | Controller Function Checker | Sound Box | GD-Writer | C1/C2 Checker | Dev.Cas | GD-ROM Duplicator
Online Services/Add-ons Dreamarena | SegaNet | WebTV for Dreamcast | Modem | Modular Cable | Modular Extension Cable | Broadband Adapter | Dreamphone
Connector Cables Onsei Setsuzoku Cable | RF Adapter | Scart Cable | S Tanshi Cable | Stereo AV Cable | VGA Box

Dreamcast MIDI Interface Cable | Neo Geo Pocket/Dreamcast Setsuzoku Cable | Taisen Cable

Misc. Hardware Action Replay CDX | Code Breaker | Kiosk | MP3 DC | MP3 DC Audio Player | Official Case | Treamcast
Third-party accessories Controllers | Controller converters | Miscellaneous
Unreleased Accessories DVD Player | Zip Drive | Swatch Access for Dreamcast | VMU MP3 Player
Arcade Variants NAOMI | Atomiswave | Sega Aurora