Actions

Sega Dreamcast

From Sega Retro

Dreamcast logo.svg
Dreamcast.jpg
Fast facts on Sega Dreamcast
Manufacturer: Sega
Variants: Sega NAOMI, Atomiswave, Sega Aurora
Main processor: Hitachi SH-4
Release Date RRP Code
Sega Dreamcast
JP
¥29,800 HKT-3000
Sega Dreamcast
US
$199.00 HKT-3020
Sega Dreamcast
DE
499DM €? HKT-3030
Sega Dreamcast
ES
?Pts €? HKT-3030
Sega Dreamcast
FR
?FF €? HKT-3030
Sega Dreamcast
UK
£199.99 Media:CVG UK 215.pdf[2] HKT-3030
Sega Dreamcast
AU
$499.00 ?
Sega Dreamcast
BR
R$899,00 ?
Sega Dreamcast
AS
? HKT-3010

The Sega Dreamcast (ドリームキャスト) is a home video game console manufactured by Sega as a successor to the Sega Saturn. It was originally released in November 1998, becoming first machine to be released in what is now known as the sixth generation of video game consoles, sharing a platform with the PlayStation 2, Nintendo GameCube and the Xbox.

The Dreamcast was Sega's last home console, developed primarily to detoxify the Sega brand and rekindle the trust and market success seen in the days of the Sega Mega Drive. However, faced with significant competition going into 2001, the Dreamcast project was cancelled, with Sega pulling out of the console hardware business it had been persuing for nearly twenty years. Roughly 10.6 million Dreamcast consoles have been sold worldwide.

An arcade counterpart to the Dreamcast exists as the Sega NAOMI.

Hardware

The Dreamcast is a small, white box with aesthetics designed to appeal to a wide-ranging audience. It was envisioned as an "128-bit" "super console", designed to leapfrog "32-bit" and "64-bit" contemporaries in the form of the PlayStation and Nintendo 64, respectively (although from a technical standpoint, its main processor deals in 32-bit or 64-bit instructions, with the 128-bit figure coming from the graphics hardware). Incidentally the Dreamcast was the last home console to use "bits" as a selling point, with processing capabilities now typically measured in other ways.

Taking design cues from the Nintendo 64 and the Sega Saturn, the Dreamcast contains four control ports, a removable modem, disc drive and an extension port (as well as the expected AV and power inputs). It is not backwards compatible with any prior Sega hardware or software (although its controller derives from the Saturn's 3D Control Pad), and operates in much the same way as the Saturn (and PlayStation) does, with a configurable settings and memory management accessed through a BIOS screen.

The Dreamcast uses a proprietary format of storage called GD-ROMs for games in order to circumvent software piracy, a strategy that ultimately backfired when the first run of discs had a high rate of defects. The format was also cracked fairly quickly (and in some cases, the pirated games were released before the legitimate versions). Sega largely had themselves to blame for the high levels of Dreamcast piracy—their use of the GD-ROM format was completely undermined by the console's support for the Mil-CD format, which allowed the console to boot from a standard CD-R. Mil-CD support was removed from the final Dreamcast revisions toward the end of the console's life.

The GD-ROM format also put the console at a disadvantage when competing against the PlayStation 2 - the PS2 used DVDs, and could therefore run DVD videos making it an inexpensive DVD player as well as a video game console. DVD-ROMs also have more stoage space, allowing for bigger games (though the initial run of PS2 games used a blue CD-ROM format). Sega looked into DVD technology during the Dreamcast's development but claimed it was too expensive.

The Dreamcast was the first video game console to ship with a built-in 56k modem, with broadband adapters being made available later on in certain regions. This allowed the system to connect to the internet using a custom, fully-functional web browser and e-mail client. Many games released for the Dreamcast shipped with online play modes, the most popular being Phantasy Star Online and the Sega Sports lineup (now published under the ESPN label). Although other consoles before the Dreamcast had network gaming support, such as the Sega Saturn's NetLink and the Sega Mega Drive's XB∀ND, the Dreamcast was the first game console to include this ability out of the box and is therefore considered the first internet-enabled home game system.

The Dreamcast has a modest hacking enthusiast community. The availability of Windows CE software development kits on the Internet—as well as ports of Linux (LinuxDC) and dreamcast NetBSD operating systems to the Dreamcast—gave programmers a selection of familiar development tools to work with, even though they do not really support the high speed graphics. A homebrew minimal operating system called Kallistios offers support for most hardware, while not offering multi-tasking, which is superfluous for games. Many emulators and other tools (MP3, DivX players, and image viewers) have been ported to or written for the console, taking advantage of the relative ease with which a home user can write a CD which is bootable by an unmodified Dreamcast.

Sega released an arcade board, using the same technology as the Dreamcast, called Sega NAOMI, leading to many Dreamcast-exclusive games with a high level of arcade quality. They later packaged the Dreamcast into an arcade board as the Atomiswave.

Models

See also: Dreamcast consoles

Japanese Dreamcasts can be identified by the triangle at the front of the unit. Though the power LED is identical across all regions, the piece of plastic attached to the lid of the Japanese model is transparent, while in North America it is grey.

For a full list of special edition Dreamcasts, see Special Dreamcast Models.

Technical Specifications

CPU

  • CPU: Hitachi SH-4 (RISC, 2‑way Superscalar) [3]Media:SH-4 Software Manual.pdf[4]
    • Operating frequency: 200 MHz
    • Units: 128‑bit SIMD vector unit with graphic functions, 64‑bit floating‑point unit, 32‑bit fixed‑point unit
    • 128‑bit SIMD @ 200 MHz: Vector unit, geometry processor, graphic functions, DMA controller, interrupt controller Media:SH-4 datasheet.pdf[5]
    • 128‑bit graphic computational engine: Calculates geometry and lighting of polygons, creates display lists of polygons for tiling, DMA allows SH4 access to VRAM and PowerVR2 access to Main RAM, store queue mechanism (allowing high‑speed packet transfers between Main RAM and VRAM) Media:DreamcastDevBoxSystemArchitecture.pdf[6]
    • Bus width: 128‑bit internal, 64‑bit external
    • Bandwidth: 3.2 GB/s internal, 1.6 GB/s external
    • Fixed‑point performance: 360 MIPS
    • Floating‑point performance: 1.4 GFLOPS (7 MFLOPS per 16 MB/s)
    • Geometry performance: More than 10 million polygons/sec, with lighting calculations (140 FLOPS per polygon)

Graphics

Graphical specifications of the Dreamcast: Media:Dreamcast Hardware Specification Outline.pdf[7]Media:DreamcastDevBoxSystemArchitecture.pdf[6]Media:PowerVR2DCFeaturesUnderWindowsCE.pdf[8]

  • GPU: 2 core processors (SH‑4 SIMD, PowerVR2)
    • Core units: 5 units (SH‑4 SIMD, 4 PowerVR2 cores)
  • GPU Geometry Processor: Hitachi SH‑4 SIMD @ 200 MHz
  • GPU Rasterizer: NECVideoLogic PowerVR2 CLX2 (PVR2DC/HOLLY) @ 100 MHz
  • PowerVR2 Cores: Tile Accelerator (TA), Image Synthesis Processor (ISP), Texture & Shading Processor (TSP), RAMDAC
    • TA: Tile renderer, partitions infinite strip polygon data, divides polygons into tiles, performs tile clipping, generates object lists, retrieves display lists from SH4 (through store queues and DMA), generates ISP/TSP parameters
    • ISP: Rasterizer, depth‑sorting, RLE tile/polygon compression, parallel‑processing of tiles/polygons at high speeds (1 clock cycle per vector, 32 pixels per clock cycle)
    • TSP: Shader and texture‑mapping unit, avoids shading/texturing overdrawn pixels/tiles and back‑facing polygons to maximize bandwidth for on‑screen pixels/tiles and front‑facing polygons
    • RAMDAC: 230 MHz [9]
  • PowerVR2 Capabilities:
  • Display Resolution: 320×240 to 800×608 pixels, interlaced and progressive scan, TV and VGA
    • Internal resolution: 320×240 to 1600×1200 pixels [9]
  • Color Depth: 16‑bit RGB to 32‑bit ARGB, 65,536 colors (16‑bit color) to 16,777,216 colors (24‑bit color) with 8‑bit (256 levels) alpha blending, YUV and RGB color spaces, color key overlay [15]
  • Framebuffer:
  • Geometry Performance: 23 million vertices/sec (60 FLOPS per polygon) [16]
  • Polygon Geometry: Effective performance, including overdrawn and back‑facing polygons not drawn on screen
    • 11 million polygons/sec (130 FLOPS per polygon)
    • More than 10 million polygons/sec: Lighting (140 FLOPS per polygon) [3]
  • Rendered On‑Screen Polygons: Front‑facing polygons drawn on screen, not including overdrawn and back‑facing polygons (including them, effective performance is more than than 10 million polygons/sec) [3][17]
    • 7 million polygons/sec: Lighting, textures, shadows,[9] trilinear filtering [18]
    • 6 million polygons/sec: Lighting, textures, trilinear filtering, Gouraud shading (243 FLOPS per polygon)
    • 3.3 million polygons/sec: Lighting, textures, trilinear filtering, Gouraud shading, bump mapping (430 FLOPS per polygon) Media:PowerVR2DCFeaturesUnderWindowsCE.pdf[19]
  • Rendering Fillrate: [3]Media:DreamcastDevBoxSystemArchitecture.pdf[6]
  • Texture Fillrate:
    • 200–500 MTexels/s: Effective fillrate (including overdrawn and back‑facing textures)
    • 100 MTexels/s: Front‑facing textures drawn on screen
  • VRAM: 8 MB (unified framebuffer/polygon/texture memory) Media:DreamcastDevBoxSystemArchitecture.pdf[6][21]
    • Framebuffer: 4 KB to 7500 KB
    • Polygons: Up to 6511 KB (10 million polygons/sec, 32‑bit precision, 40 bytes per polygon)
    • Textures: Up to 8188 KB (63.8 MB with maximum compression)
    • Note: Main RAM can also be used to store textures and polygon display lists
  • Full Motion Video: MPEG decoding, video compression, 320×240 to 640×320 and 320×480 video resolutions, 3D polygons can be superimposed over FMV video [3]

Sound

Memory

Bandwidth

  • System RAM Bandwidth: 1.8 GB/s Media:Dreamcast Hardware Specification Outline.pdf[7]
  • System ROM Bandwidth: 20 MB/s (16‑bit, 10 MHz)
  • Internal Processor Memory Bandwidth: 2.7 GB/s
    • SH4: 1.6 GB/s (64‑bit, 200 MHz)
    • PowerVR2: 800 MB/s (64‑bit, 100 MHz)
    • AICA: 256 MB/s (32‑bit, 67 MHz)
  • GD‑ROM Drive: 1.8 MB/s transfer rate, 250 milliseconds access time

BIOS

BIOS Revisions
BIOS Version Machine Download
1.004 Sega Dreamcast (Commercial-Early) 1.004 (Japan) (info) (912 kB)
1.01d Sega Dreamcast (Commercial) 1.01d (North America) (info) (886 kB)
1.01d (Europe) (info) (886 kB)
1.01d (Japan) (info) (885 kB)
1.011 Sega Dreamcast (HKT-0120 Devbox) 1.011 (HKT-0120 Devbox) (info) (992 kB)

Other Specifications

  • Operating Systems:
  • Inputs: Four ports that can support a digital and analog controller, steering wheel, joystick, keyboard, mouse, and more
  • Dimensions: 189mm x 195mm x 76mm (7 7/16" x 7 11/16" x 3")
  • Weight: 1.9kg (4.4lbs)
  • Modem: Removable; Original Asia/Japan model had a 33.6 Kbytes/s; models released after 9 September 1999 had a 56 Kbytes/s modem
  • Sega Dreamcast Broadband Adapter: these adapters are available separately and replace the removable modem
    • HIT-400: "Broadband Adapter", the more common model, this used a RealTek 8139 chip and supported 10/100mbit
  • HIT-300: "Lan Adapter", this version used a Fujitsu MB86967 chip and supported only 10mbit
  • Storage: "Visual Memory Unit" (VMU) 128 Kb removable storage device
  • Input devices: (4 custom controller ports)
  • Output devices:
  • Add-ons:

History

Main article: History of the Sega Dreamcast

Launch Titles

Japan

North America

Europe

Media:DreamcastMagazine UK 03.pdf[25]

Gallery

Hardware Diagrams

Logos

Promotional material

Print advertisements

Television advertisements

Other advertisements

References

  1. File:CVG UK 216.pdf, page 52
  2. File:CVG UK 215.pdf, page 59
  3. 3.0 3.1 3.2 3.3 3.4 3.5 3.6 3.7 3.8 Sega Dreamcast: Implementation (IEEE)
  4. File:SH-4 Software Manual.pdf
  5. File:SH-4 datasheet.pdf
  6. 6.00 6.01 6.02 6.03 6.04 6.05 6.06 6.07 6.08 6.09 6.10 File:DreamcastDevBoxSystemArchitecture.pdf
  7. 7.0 7.1 7.2 7.3 7.4 7.5 File:Dreamcast Hardware Specification Outline.pdf
  8. 8.0 8.1 File:PowerVR2DCFeaturesUnderWindowsCE.pdf
  9. 9.0 9.1 9.2 http://segatech.com/technical/gpu/index.html
  10. Hideki Sato Sega Interview (Edge)
  11. Tiling Accelerator Notes
  12. Zombie Revenge (21 January 2000)
  13. PowerVR (Dreamcast Hardware)
  14. Dreamcast Comparison
  15. Neon 250 Specs & Features
  16. Computer Graphics: Principles and Practice (Page 868)
  17. Floating-Point Calculations
  18. Vintage Game Consoles: An Inside Look at Apple, Atari, Commodore, Nintendo, and the Greatest Gaming Platforms of All Time (Page 277)
  19. File:PowerVR2DCFeaturesUnderWindowsCE.pdf, page 11
  20. File:Edge UK 067.pdf, page 11
  21. Polygon Calculations
  22. Dreamcast & Saturn Specifications
  23. File:SH-4 Software Manual.pdf, page 25
  24. File:Dreamcast Hardware Specification Outline.pdf, page 6
  25. File:DreamcastMagazine UK 03.pdf, page 7
Sega Home Video Game Systems
83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 00 01 02 03 04 05 06 07 08 09 10 11
SG-1000 SG-1000 II Mega Drive Mega Drive II
SC-3000 Mega-CD Mega-CD II Genesis 3
Sega Mark III Saturn
Master System Master System II
Game Gear
32X Dreamcast
Pico Beena
Sega Dreamcast Hardware
 Dreamcast Variations   Special Dreamcast Models
 Console Add-ons   Dreamcast Karaoke | Dreameye
Game Controllers   Controller | Arcade Stick | Fishing Controller | Gun (Dream Blaster) | Racing Controller | Maracas | Twin Stick | Keyboard | Mouse
Controller Add-ons   Jump Pack (Third Party) | Microphone | VMU (Third Party)
Controller Connectors DC Tsunaident 123 | Dream Connection 2 in 1 | Dream Connection 4 in 1 | Dream Connection II | Super Converter 3 | Total Control | Total Control 2 | Total Control Plus | Total Control 3 | Total Control 5
Development Hardware Dreamcast Dev.Box | Controller Box | Dreamcast Controller Function Checker | Sound Box | GD-Writer | C1/C2 Checker | Dev.Cas | Dreamcast GD-ROM Duplicator
Online Services/Add-ons   Dreamarena | SegaNet | WebTV for Dreamcast | Modem | Modular Cable | Dreamcast Modular Extension Cable | Broadband Adapter | Dreamphone
Connector Cables   5-Pin Cable | Audio Cable | RF Adapter | Scart Cable | Stereo AV Cable | VGA Adapter

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

Misc. Hardware   Action Replay | Code Breaker | Kiosk | MP3 DC | MP3 DC Audio Player | Treamcast
Unreleased Accessories   Dreamcast DVD Player | Dreamcast Zip Drive | Swatch Access for Dreamcast | VMU MP3 Player