
Sega Genesis / Mega Drive
Sega's 16-bit console known for its speed and attitude. Genesis does what Nintendon't - featuring Sonic and countless action classics.
Technical Specifications
CPU
Motorola 68000 @ 7.67 MHz (main), Zilog Z80 @ 3.58 MHz (sound/sub)
GPU
Yamaha YM7101 VDP (Video Display Processor), 320x224 or 256x224 resolution, 512 color palette, 64 simultaneous on-screen colors (up to 183 with tricks), 80 sprites, 2 scrolling background planes, shadow/highlight mode
Memory
64 KB main RAM, 64 KB VRAM, 8 KB Z80 sound RAM
Storage
Cartridge-based ROM, up to 40 Mbit (5 MB) standard, some games with bank switching exceeding this
Display
320x224 (NTSC) or 320x240 (PAL) pixels, interlace mode for 320x448, hardware horizontal and vertical scrolling
Audio
Yamaha YM2612 FM synthesis (6 channels, one convertible to DAC for PCM samples) + TI SN76489 PSG (3 square waves + 1 noise), stereo output via headphone jack (Model 1)
Media
64-pin cartridge
History
Hardware Variants
Mega Drive / Genesis Model 1 (1601)
Released: October 29, 1988
Original design featuring rounded top, headphone jack with volume control, HD graphics label, and expansion port.
Mega Drive 2 / Genesis Model 2 (1631)
Released: May 1, 1993
Cost-reduced redesign: smaller, lighter, no headphone jack, simplified audio circuit. Removed EXT port.
Genesis 3 (1639)
Released: January 1, 1998
Budget model manufactured by Majesco in North America only. Very compact, no expansion port (incompatible with Sega CD and 32X).
Sega Nomad
Released: October 1, 1995
Portable Genesis with built-in 3.25-inch backlit LCD screen. Played standard Genesis cartridges on the go. Short battery life (~2 hours on 6 AA batteries).
Mega Jet
Released: March 1, 1994
Handheld Genesis without a screen, designed originally for Japan Airlines in-seat entertainment. Required external display.
Development Story

Mortal Kombat
• 1993

Sonic the Hedgehog
• 1985

Sonic the Hedgehog 3
• 1994

Sonic the Hedgehog 2
• 1992

Sonic Classic Heroes
• 2023

Sonic & Knuckles
• 1985

Tiny Toon Adventures: Buster's Hidden Treasure
• 1993

Teenage Mutant Ninja Turtles: Shredder's Re-Revenge
• 2023

Sonic Boom
• 1994

Sonic 3D Blast
• 1996

Golden Axe
• 1989

Streets of Rage 3
• 1994
About the Sega Genesis / Mega Drive
The Sega Genesis / Mega Drive (Genesis) is a home video game console manufactured by Sega. Released on October 29, 1988, it belongs to the 4th generation of gaming hardware.
With a library of 126+ games, the Genesis remains one of the most popular platforms for retro gaming enthusiasts. Our wiki provides detailed information about the hardware specifications, variants, and game library to help you understand and appreciate this classic gaming system.
Whether you're researching emulation compatibility, collecting vintage hardware, or simply exploring gaming history, the Genesis encyclopedia entry offers comprehensive information about this iconic gaming platform.