Cartridge

A cartridge is a plastic case which houses the ROM chip that stores a game's data, and in some cases also contains additional hardware such as the CR2032 SRAM. Some examples of cartridge-based systems include the Sega Mega Drive / Genesis, Sega Master System and Sega Game Gear.

Genesis cartridge features

Lock-On

• The Sonic & Knuckles cartridge has another cartridge slot on top of it, similar to Game Genie and Pro Action Replay carts. This is known as Lock-On Technology.

J-Cart

• The term "J-Cart" refers to the special carts released by Codemasters that had two extra joystick ports built into the cartridge. This permitted four-way gameplay without a multitap adapter. Only six J-Carts were released: Pete Sampras Tennis, Pete Sampras Tennis 96, Micro Machines 2, Micro Machines 96, Micro Machines Military Edition, and Super Skidmarks. All were later re-released as standard cartridges.

Sega Virtua Processor

• Virtua Racing contains a custom-designed DSP chip (known officially as SVP, Sega Virtua Processor), allowing for enhanced graphics and sound capabilities. This chip essentially serves as an extra processor, allowing the game to produce polygons that would be impossible to create using a standard Mega Drive/Genesis. This extra power cost extra, though, with the game costing around $100 in total. Interestingly, this game was the first to showcase the power of the SVP chip - plans were underway to produce more games using this chip, using a "Modular Converter" cartridge to cut production costs. This Converter would contain the SVP chip, with the enhanced game designed to use the SVP chip plugging into the top of the unit. However, due to the costs of production against the Mega Drive/Genesis' age and falling popularity, the project was dropped. Virtua Racing also has a cartridge roughly one-and-a-half times the size of a usual Mega Drive/Genesis cartridge due to the added chip, and is incompatabile with the Sega 32X addon.

Specifications

See Sega Mega Drive Technical Specifications for standard Mega Drive specifications

• GPU: Samsung SSP1601 @ 23 MHz (25 MIPS)
  • DSP core: 16-bit fixed-point arithmetic, 25 registers (8 general, 8 external, 8 pointer, 1 status)
  • ALU: 32-bit, status register
• Graphics: 3D polygon graphics: 9000 polygons/sec
• Audio: 2 PWM channels
• Memory: 2179 KB (2.128 MB)
  • RAM: 131 KB (2 KB instruction cache, 1 KB SRAM cache, 128 KB FPM DRAM)
  • ROM: 2 MB
• RAM bandwidth:
  • SRAM cache: 43.869018 MB/sec (16-bit, dual-bank, 23 MHz)
  • FPM DRAM: 34.679066 MB/sec (16-bit, 18.181818 MHz, 55 ns cycles)