Sega Saturn Internal Memory Mod with FRAM – no battery required
@SegaSaturn
Published in
SegaSaturn
· 28 Feb 2021
... UPD43257B Pinout of FM1808 (my candidate replacement chip) The pinouts are almost perfect matches except for one pin. The UPD43257B has an active-high CE signal on pin 22 (driven by signal SCE2 on the schematic) whereas the FM1808 has an active-low #OE signal on pin 22. Tracing back the SCE2 on the Sega Saturn Schematics I found that it is originating from a battery management IC. This type of chip usually prevents bad writes during power down cycles. Clearly, this signal would not be necessary fo ...