Sega Mega-CD/Technical specifications
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- Back to: Sega Mega-CD.
Technical specifications for the Sega Mega-CD.
The following are upgrades over the Sega Mega Drive technical specifications.
- See Sega Mega Drive technical specifications for details of the base Mega Drive hardware
- Main CPU: Motorola 68000 16-bit processor running at 12.5 MHz
- Same as the Mega Drive. Acts as a co-processor along with the Mega Drive CPU.
- Bus width: 16-bit
- Instruction set: 16-bit and 32-bit instructions, 16 registers
- Performance: 2.19 MIPS
- Co-processor: Motorola 68000 (Mega Drive CPU) running at 7.67 MHz
- Bus width: 16-bit
- Performance: 1.34225 MIPS
- GPU: Same as base Mega Drive
- GFX co-processor: Sega 315-5548 Custom ASIC
- Bus width: 32-bit (2x 16-bit)
- Bus clock rate: 6.25 MHz (25 MB/s bandwidth)
- Transformed graphics tiles are DMA'd to the main VRAM for display.
- Full motion video: Video size from 1/4 to full screen, advanced compression scheme, software-based upgrade
- On-screen colors available in Cinepak and TruVideo modes: 128–256 colors
- Sprites/Tilemaps: The Mega-CD features enhancement effects such as scaling and rotation, similar to Sega's Super Scaler arcade hardware and that of the "Mode 7" effect employed by the Super NES. While Mode 7 only supports the scaling and rotation of tilemap backgrounds, the Sega CD supports the scaling and rotation of both the sprites and the tilemap backgrounds.
- DMA transfer rates: 3.467179 MB/s (VRAM), 6.934358 MB/s (CRAM/VSRAM)
- Transfer rates during active display: 1.625 MB/s (VRAM), 3.25 MB/s (CRAM/VSRAM)
- Read/Write fillrate: 6.934358 MPixels/s
- Write fillrate during active display: 3.25 MPixels/s
The Mega-CD adds 10 sound channels to the 10 provided by the Mega Drive's sound chips.
- CD Digital Audio
- 2-channel stereo
- 44.1 kHz sampling rate
- 16-bit PCM audio depth
- Sound format: 8-bit sign/magnitude monaural PCM (with "stereo" support by allowing each channel to have different volumes on both left and right channels)
- Maximum sample rate: 32 kHz
- PCM audio depth: 16-bit
- Bus width: 8-bit
- 16-bit DAC
- 8x internal over-sampling digital filter
- Frequency Range: 20 Hz - 20 KHz
- Signal-to-Noise Ratio: > 90 dB @ 1K
- Channel Separation: > 90 dB
- Input: Mixer cable for Mega Drive Model 1 compatibility.
- Output: Stereo RCA connectors.
- System Boot ROM: 1 Mbit (128 KB)
- External Memory Card: 1 Mbit (128 KB) CD BackUp RAM Cart
- System RAM bandwidth: 62.5 MB/sec (3 buses, 56-bit bus width)
- 500 MB CD-ROM discs (equivalent to 62 min of audio data)
- Access time: 800 ms
- 1/4 screen B/W footage video: 1.5 to 4 hours
- 1/4 screen color footage: 45 minutes
- CD-ROM drive transfer rate: 150 Kbytes/s (1x)
(Above specs prior to compression)
- Main article: Sega Mega-CD/Boot ROM.
- Size: 1 Mb (128 KB)
- Used for games, CD player, CD+G viewing, karaoke (limited to Japanese systems) and regional lockout
- Dimensions: 301 mm (11.85") x 212.5 mm (8.366") x 112.5 mm (4.429")
- Mass: 1.4 kg (3lb 1.384oz)
- ↑ 1.0 1.1 File:MCD MaintenanceManual Export RevA.pdf, page 102
- ↑ 2.0 2.1 Sega CD programming FAQ (1998-12-06)
- ↑ File:MCDHardware Manual PCM Sound Source.pdf
- ↑ 4.0 4.1 File:MCD MaintenanceManual Export RevA.pdf
- ↑ File:TC511664B datasheet.pdf
- ↑ File:TC51832 datasheet.pdf
- ↑ File:MB8464A datasheet 2.pdf
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|Hardware||Mega CD (Asia | North America | Europe (West | North | South | Central and East) | South America | Australia | Africa)|
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|Misc. hardware||CD BackUp RAM Cart | Mega-CD Karaoke | Pro CDX|
|Development tools||SNASM Mega-CD | PsyQ Mega-CD SDK | PSY-Q CD Emulation System (Mega-CD)|
|Unreleased hardware||Game Genie|