Sega Mega Drive - Hardware revisions
(Пришло 5, Ушло 4) / Рейтинг 0
VA0 (JPN), VA1 (JPN),VA2 (USA, High Definition Graphics) ,VA3 (USA, High Definition Graphics) ,VA4 (JPN) , VA4 (PAL), VA5 (JPN),VA6 (JPN) , VA6 (USA, High Definition Graphics), VA6.5 (PAL), VA6.8, VA7 (USA)
Components:
M68K CPU: Signetics SCN68000C8N64
M68K memory: 2x HM65256BLSP-15 (32Kx8 PSRAM, 150 ns)
Z80 CPU: Zilog Z0840004PSC
Z80 memory: TMM2063P - 10 (8Kx8 SRAM, 100 ns)
I/O chips: Sega 315-5308, Sega 315-5309, Signectic 74LS00N, 74LS161AN, 74F161AN, 74LS74AN (DIP-16)
VDP: Sega 315-5313 (Yamaha YM7101)
Video RAM: 2x HM53461ZP-12 (64Kx4 VRAM 120 ns)
Headphone amp: Sony CXA1034
Video encoder: Sony CXA1145
FM synthesizer: Yamaha YM2612
Due to a last-minute issue with the VDP in H40 mode, additional clock circuitry had to be added during manufacturing. This circuitry is present on a daughterboard in the center of the PCB, and contains the master oscillator (53.6931 MHz, NTSC), a 74LS74 (dual D-type flip-flops), and two 74LS161s (4-bit counter).
VA0 (USA)
Components:
M68K CPU: Hitachi HD68HC000CP8
M68K memory: Toshiba TC51832AFL-10
Z80 CPU: Toshiba 84C00AU-6
Main ASIC: Sega 315-5487-01
Video Encoder: Samsung KA2195D
Amplifier: Texas Instruments 311223J
Подробнее про Sega Mega Drive - Hardware revisions