U1
Other components on Sega Master System
About this component
The Z80 runs all game and BIOS code, talking to the VDP, the 315-5216 I/O controller, 8 KB of work RAM and the cartridge/card slots. On the Master System it sits as IC1 on the through-hole board. A 4 MHz-rated part is used but run at roughly 3.58 MHz. NEC D780C-1 and Zilog parts are pin-compatible, so either can be used as a replacement. Part variants: Early NTSC Model 1 boards (171-5379) used an NEC D780C-1 Z80 clone; later Model 1 (171-5532) and NTSC Master System II (171-5926A) boards use the Zilog Z0840004PSC. The Japanese Mark III used NEC D780C-1 (Japan) or Goldstar Z8400A PS (Korea).
What it does on this board
8-bit Z80 CPU @3.58MHz.
Pinout & readings
Pinout and readings are for members
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- The full pinout — 40 pins with what each one does
- Datasheets