* The pinout of top, unpopulated blob (let's call it U4) is exactly like the AX5202P, without WRAM and PRG-A18 pins). There are also extra pins wired to it: CPU-A12, CPU-A2, CPU-A1 (wonder which mapper can take use of them - JY Company?), and two input pins (mode select?)
* The pinout of bottom, populated blob chip (let's call it U5) is:
Code: Select all
.---. CPU D0 -> | | -- +5V CPU D1 -> | | -> PRG /CE CPU D2 -> | | <- M2 CPU D4 -> | | <- CPU A14 PRG A14 <- | | <- CPU R/W PRG A15 <- | | <- CPU /ROMSEL PRG A16 <- | | -- GND PRG A17 <- | | -> CIRAM A10 '---'
* The unpopulated bottom SO14 chip is meant to be 74*74 - its output would change every reset to allow 2 different games
It turns out the PCB is quite versatile - it allows to be used as:
* NROM (no extra chips need to be present)
* MMC3 (U4)
* UNROM/ANROM (U5)
Unfortunately the mapper blob is broken, but EEPROM was good. It holds the Mega Girl Another Fight Story game.