Sega Mega-CD

The Sega Mega-CD (Japanese:メガCD) is an add-on device for the Sega Megadrive released in Europe and Japan. (The North American version is the Sega CD).

The device will allow the user to both play audio CDs and specially designed game CDs. It also has CD+G capabilities.

The development of the Sega CD was top secret; game programmers didn't know what they were designing for until the Sega CD was finally revealed at Tokyo Toy Show in Japan. The Sega Mega-CD in Japan was desgned to be in competition with the PC Engine, which had a CD module. A combination version of the aforementioned system, the Duo, would later be released. The Sega Mega-CD was not meant to compete with the Super Famicom, which was released in Japan, nor did it compete with Super Nintendo Entertainment System in Europe.

The Sega Mega-CD was first released in Japan in 1991 for ¥49,800. Initially, it was a great success because of the inherent advantages of CDs (high storage space and low media cost) and the fact that it had a nice RPG base. The system sold 100,000 units during the first year of release in Japan. Cost issues prevented more units from being sold. Sega of Japan did not inform their North American division of their Mega-CD console until a few months later. NEC did horribly with their PC Engine CD in Japan and the Turbo Duo in Europe.

At first, the Mega-CD was a CD tray unit that sat under the console. The Sega Mega-CD 2 was a smaller, cheaper top loading unit that sat next to the Sega Megadrive.

Europe had their Mega-CD expensively priced. It was released in April 1993 in the United Kingdom for £270. Only 4% of European Megadrive owners ended up having a Mega-CD because of its cost. The Megadrive was a very successful console in Europe. 60,000 of the 70,000 Mega-CD's shipped to Europe were sold by August 1993. Some European countries wouldn't get the Mega-CD until its redesign, which also slowed sales.

The Australians got their Mega-CD on 19 April, 1993.

The Sega Mega-CD exists in the following models:

• Sega Mega-CD I (Sega CD I in North America)
• Sega Mega-CD II (Sega CD II in North America) had a faster CD-ROM drive
• JVC Wondermega (Xeye in North American release, never released in Europe), was a all-in one Sega CD unit
• Sega Multimega (named Sega CDX in North America)
• Pioneer LaserActive Sega CD module, an add-on device you could add to a Laseractive Pioneer Laserdisc player.

What it adds to the Megadrive:

• 10 extra sound channels to complement the sound from the Megadrive Z80 sound processor.
• sprite enhancement features such as scaling and rotation, similar to that of the Super Famicom/SNES Mode 7.

Specs:

Main CPU: Motorola 68000 @ 12.5 MHz

• Same as the Megadrive... runs with it... except the Genesis CPU runs at the slower clock speed: 7.9 MHz

Graphics Processor: Custom ASIC RAM:

• 6 Mbit Main RAM
• 512 Kbit PCM Waveform Memory
• 128 Kbit CD-ROM data cache memory
• 64 Kbit Internal Backup RAM

Colours:

• Originally 64, same as Megadrive
• Using programming tricks, can get 128 colors via HAM "Hold and Modify"
• Using Cinepak and TruVideo:
  • 128 to 256 colours
  • Increase screen size from 1/4 to full
  • Advanced compression scheme
  • Software-based upgrade

Storage capability

• Approximately 500 MB of data (62 min of audio data equivalent)
• 1/4 screen B/W footage video: 1.5 to 4 hours
• 1/4 screen color footage: 45 minutes
• Above specs are prior to compression

Transfer rate of Sega CD: 150 kbytes/sec (1X) Boot ROM:

• 1 Mb contains:
  • CD Game Bios
  • CD Player Software
  • CD+G Software

  Bios Version     Machine
      1.00         Original Mega CD
      2.00         Mega CD2 (Sega CD2 in North America)
      2.05         Mega CD2
      2.10         Mega CD2
      2.21         Sega Mega LD (Japan), Sega Multimega (Europe) (CDX in North America)

Access time: 800 ms Sound Circuitry:

• PCM Sound
  • Stereo: 8 channels
• 32 KHz Maximum sampling wavelength
• 16 Bit D/A converter
• 8X internal over-sampling digital filter

Audio:

• Frequency Range: 20Hz - 20 KHz
• Signal-to-Noise Ratio: >900dB @ 1K
• Channel Separation: >900 dB

Output: RCA Pin Jack x2 (L/R) Dimensions: 301mm x 212.5 x 112.5 Weight: 3.1 lbs