Drakon
Active Member
There's a lot of famicom games that used custom audio chips inside the carts. Flash cards like the nes powerpak and the famicom n8 sound noticably different than the real audio chips inside these carts. I decided to buy the actual carts of the games that interest me and convert the rpgs into english. Here's the first batch:
Esper dream 2 and madara were very easy, straight eprom pinouts no rewiring necessary. Just breed was difficult:
Just breed required a good amount of rewiring, also the game rom wouldn't work on a rgb system until I patched the rom in a hex editor to disable the colour emphasis bits, otherwise I'd just get a white screen.
Moving onto a more insane conversion is megami tensei 2. Megami tensei 2 the official pcbs are all globtop, I needed to convert another game that's not glob top but contains the same audio chip as megami tensei 2 into megami tensei 2. The only game that's like this is dragon ninja, except the dragon ninja pcb needs some serious modding to be turned into megami tensei 2. First I wired up the eproms (at first flash chips later I used eproms) using maskrom pinouts from nesdev and following traces to confirm. Once I got that working I used schematics from a polish forum to wire up the 8k ram chip that megami tensei 2 needs for savedata, hand wiring a ram chip is interesting. Next I built a battery circuit again using a schematic from this polish forum, I harvested some diodes from an old mario world cart I never play anymore to build the circuit, both the ram and the battery circuit work great! Lastly I used a combination of japanese blogs and looking at the audio circuit on my megami tensei 2 glob top pcb to figure out the audio circuit of the real thing. The audio wiring is luckily very simplistic. Here's the cart:
And here's the proof that the audio is exactly the same as the legit cart:
The last conversion I did is the most difficult (even worse than megami tensei 2 if you can believe this). I wanted to play gimmick! for the famicom but I didn't feel like paying the insane prices the real cart demands. I read that sunsoft fme7 famicom games made around the same time as gimmick would sometimes contain the sunsoft 5b mapper / audio chip (but most of the time not). The only way to find out if you got a sunsoft 5b chip is to open your cart and look at the pcb. The sunsoft 5b is a fme7 chip with additional audio capabilities, the 5b is the only version of the chip with the additional audio. I bought a cheap gremlins 2 on ebay and by fluke it contained a sunsoft 5b chip. Restoring the audio circuit of the sunsoft 5b required me to desolder the entire teeny sunsoft 5b surface mount chip, cut a trace on the pcb underneath the chip, and solder the sunsoft 5b back onto the pcb. Without doing this one of the sunsoft 5b audio pins is grounded and the audio circuit won't work at all (thanks a lot sunsoft..). Next I had to attach 4 wires to the tiny sunsoft 5b chip legs, three for the audio circuit and the fourth wire to add support for a larger prg rom. Wiring the gimmick prg rom requires wiring a 32 pin eprom into a 28 pin spot so that took some rewiring.
To restore the audio circuit I used a schematic posted on a japanese blog and compared it to pcb scans of a real gimmick pcb, seems like the real thing. When I first built my gimmick cart to test the audio of the cart I didn't have the right parts for the audio circuit so I used the wrong parts to wire it up just for the sake of testing that it even works. Later I built the official circuit, it does work, but my "spare parts" circuit actually sounds noticably better on the av famicom so I'm using that. Here's the schematic of my "spare parts" audio circuit:
Here's the cart:
This cart sounds better than the retail version of the game, it uses the same audio chip and is using my improved audio circuit. Here's how it sounds on the av famicom:
Esper dream 2 and madara were very easy, straight eprom pinouts no rewiring necessary. Just breed was difficult:
Just breed required a good amount of rewiring, also the game rom wouldn't work on a rgb system until I patched the rom in a hex editor to disable the colour emphasis bits, otherwise I'd just get a white screen.
Moving onto a more insane conversion is megami tensei 2. Megami tensei 2 the official pcbs are all globtop, I needed to convert another game that's not glob top but contains the same audio chip as megami tensei 2 into megami tensei 2. The only game that's like this is dragon ninja, except the dragon ninja pcb needs some serious modding to be turned into megami tensei 2. First I wired up the eproms (at first flash chips later I used eproms) using maskrom pinouts from nesdev and following traces to confirm. Once I got that working I used schematics from a polish forum to wire up the 8k ram chip that megami tensei 2 needs for savedata, hand wiring a ram chip is interesting. Next I built a battery circuit again using a schematic from this polish forum, I harvested some diodes from an old mario world cart I never play anymore to build the circuit, both the ram and the battery circuit work great! Lastly I used a combination of japanese blogs and looking at the audio circuit on my megami tensei 2 glob top pcb to figure out the audio circuit of the real thing. The audio wiring is luckily very simplistic. Here's the cart:
And here's the proof that the audio is exactly the same as the legit cart:
The last conversion I did is the most difficult (even worse than megami tensei 2 if you can believe this). I wanted to play gimmick! for the famicom but I didn't feel like paying the insane prices the real cart demands. I read that sunsoft fme7 famicom games made around the same time as gimmick would sometimes contain the sunsoft 5b mapper / audio chip (but most of the time not). The only way to find out if you got a sunsoft 5b chip is to open your cart and look at the pcb. The sunsoft 5b is a fme7 chip with additional audio capabilities, the 5b is the only version of the chip with the additional audio. I bought a cheap gremlins 2 on ebay and by fluke it contained a sunsoft 5b chip. Restoring the audio circuit of the sunsoft 5b required me to desolder the entire teeny sunsoft 5b surface mount chip, cut a trace on the pcb underneath the chip, and solder the sunsoft 5b back onto the pcb. Without doing this one of the sunsoft 5b audio pins is grounded and the audio circuit won't work at all (thanks a lot sunsoft..). Next I had to attach 4 wires to the tiny sunsoft 5b chip legs, three for the audio circuit and the fourth wire to add support for a larger prg rom. Wiring the gimmick prg rom requires wiring a 32 pin eprom into a 28 pin spot so that took some rewiring.
To restore the audio circuit I used a schematic posted on a japanese blog and compared it to pcb scans of a real gimmick pcb, seems like the real thing. When I first built my gimmick cart to test the audio of the cart I didn't have the right parts for the audio circuit so I used the wrong parts to wire it up just for the sake of testing that it even works. Later I built the official circuit, it does work, but my "spare parts" circuit actually sounds noticably better on the av famicom so I'm using that. Here's the schematic of my "spare parts" audio circuit:
Here's the cart:
This cart sounds better than the retail version of the game, it uses the same audio chip and is using my improved audio circuit. Here's how it sounds on the av famicom:
