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Sega · Game Console · 1987

Sega Master System

Sega master system: Zilog Z80A, 8-bit, rated for 4 MHz but runs at approximately 3.58 MHz, ROM cartridges (Mega Cartridges) held up to 4 Mbit (512 KB) of code/data storage. Released in 1985.

Chipset
Zilog Z80A, 8-bit, rated for 4 …
Resolution
256 x 192 pixels
Master System II (3006)Master System (3010)

Audio

FM audio
Japanese Master System (Oct 23, 1987) added a built-in FM audio chip (Yamaha YM2413)
Sound chip
Texas Instruments SN76489 Programmable Sound Generator (PSG)

Media

Slots
Two game input slots (cartridge slot and Sega Card slot), plus an expansion slot and two controller ports
Formats
ROM cartridges and credit-card-sized Sega Cards

Memory

RAM
8 KB
VRAM
16 KB, accessible only by the VDP via a 16-bit data bus
Card storage
Sega Cards held up to 256 Kbit (32 KB)
Cartridge storage
ROM cartridges (Mega Cartridges) held up to 4 Mbit (512 KB) of code/data

Graphics

VDP
Custom Video Display Processor designed by Sega for the Mark III, internally based on the Texas Instruments TMS9918 design (as used in the SG-1000) with added enhancements
Resolution
256 x 192 pixels
Video output
RF switch standard; Model 1 units with AV port also support composite and RGB video

Physical

Dimensions (Master System)
365 mm x 170 mm x 70 mm (14.4 in x 6.7 in x 2.8 in)
Dimensions (Sega Mark III)
318 mm x 145 mm x 52 mm (12.5 in x 5.7 in x 2.0 in)

Processor

CPU
Zilog Z80A, 8-bit, rated for 4 MHz but runs at approximately 3.58 MHz

Parts documented to fit this model — fitment grade and repair difficulty. Supplier listings are rolling out; “Find suppliers” searches the marketplace today.

Sega Master System Capacitor Kit Aftermarket A Soldering Skill 3/5 Find suppliers →
Sega Master System DC Power Jack Aftermarket A Soldering Skill 3/5 Find suppliers →

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