64MBit ExLOROM SRAM Problem
Posted: Wed May 03, 2017 7:04 am
So, I just recently got to know that LoROM games can actually be 64MBit large.
I tried to solder Wizardry VI for someone, while the game works it freezes once you save.
This is how I soldered the game on a SHVC-1A3M-XX Board with replacing the SRAM with a HY62256A:
Bent up Pin 1 and 30 of SRAM.
Soldered Pin 1 to ROM A14.
Soldered Pin 30 to ROM A13.
ROM1: MBM29F033C using TSOP Type III Adapter.
ROM2: AM29F016B using TSOP Type III Adapter.
Both piggybacked leaving the /OE lines disconnected.
Added a 74LS139 to decode A23.
Pin 1 = SNES /OE (Cart #49)
Pin 2 = SNES A23 (Cart #48)
Pin 3 = GND
Pin 4 = ROM2 /OE
Pin 5 = ROM1 /OE
Pin 8 = GND
Pin 16 = VCC
All other pins are NC.
While the game boots and runs fine from my testing so far, it crashes once you want save a character.
Anyone know what's wrong?
P.S. Even tried decoding the SRAM like HiROM with A13 and A14 being connected to A16 and A17, didn't help.
I tried to solder Wizardry VI for someone, while the game works it freezes once you save.
This is how I soldered the game on a SHVC-1A3M-XX Board with replacing the SRAM with a HY62256A:
Bent up Pin 1 and 30 of SRAM.
Soldered Pin 1 to ROM A14.
Soldered Pin 30 to ROM A13.
ROM1: MBM29F033C using TSOP Type III Adapter.
ROM2: AM29F016B using TSOP Type III Adapter.
Both piggybacked leaving the /OE lines disconnected.
Added a 74LS139 to decode A23.
Pin 1 = SNES /OE (Cart #49)
Pin 2 = SNES A23 (Cart #48)
Pin 3 = GND
Pin 4 = ROM2 /OE
Pin 5 = ROM1 /OE
Pin 8 = GND
Pin 16 = VCC
All other pins are NC.
While the game boots and runs fine from my testing so far, it crashes once you want save a character.
Anyone know what's wrong?
P.S. Even tried decoding the SRAM like HiROM with A13 and A14 being connected to A16 and A17, didn't help.