U2
Zilog Z0840004PSC
Co-CPU
DIP-40 (Model 1); QFP on Model 2
Sound / compatibility CPU
About this component
The Z80 drives the YM2612 and the PSG from its own 8 KB of RAM, leaving the 68000 free for game logic. With a Power Base Converter fitted it becomes the main CPU for Master System games. If music is missing but sound effects driven by the 68000 still work, the Z80, its RAM or the bus arbiter are good suspects. Part variants: Seen on a US VA2 Model 1 board. Model 2 VA0 uses a Z80 in a QFP package (part not confirmed). On Model 2 VA4 and Genesis 3 the Z80 is integrated into the 315-5960 / 315-6123 ASIC.
What it does on this board
Z80 @3.58MHz for audio control and Master System mode.
Pinout & readings
Pinout and readings are for members
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