Hi, I'm new and I had a few questions (go figure) and I was wondering if anyone with more experience could help me with my project. I'm just doing this for myself for fun, and I'm hoping to learn in the process.
So I've already done a gimmick reproduction on which the yamaha chip is a bit loud...I think I need a resistor on it to fix it but I am not sure where to put it. Other than that, it works fine, but any advice on that would be amazing. Regardless, that repro was much better documented and yeah it took some doing, but I more or less could easily figure it out. I decided I wanted to play The Portopia Serial Murder Case translated on real hardware since the game is very text heavy. Originally, I expected it to be fairly easy, since the game uses NROM, which is about as basic as it gets. The problem with this is that the translation uses the much more complex mapper 68 (and for what other than expanded storage, I'm not entirely sure).
My PRG and CHR chips are regular W27C020-70 EEPROMs, in a 32 pin DIP. I've already programmed them based on the translated rom, that shouldn't be a problem (assuming it's written so it can run on a real console, that is).
I've already acquired Maharaja, which uses the same mapper as the translation, seems to use the same mirroring, and has a CHR and PRG just like Portopia uses. The PRG is 28 pins, however, and I don't know how to connect my 32 pin EEPROM to it. Is it the same pins as on MMC3 cartridges? Can I just stick the CHR in as is since it's 32 pin? The game also has a battery, which portopia doesn't use, and I'm not sure if I can just remove it. I figure it's probably also a good idea to replace the 22uf electrolytic capacitor on it since it's pretty old if this works.
I was mainly wondering if this would even be possible to do (I haven't seen anyone's finished repro of the game yet) and if so, what modifications I'd need to make.
Thanks a lot for reading this.
So I've already done a gimmick reproduction on which the yamaha chip is a bit loud...I think I need a resistor on it to fix it but I am not sure where to put it. Other than that, it works fine, but any advice on that would be amazing. Regardless, that repro was much better documented and yeah it took some doing, but I more or less could easily figure it out. I decided I wanted to play The Portopia Serial Murder Case translated on real hardware since the game is very text heavy. Originally, I expected it to be fairly easy, since the game uses NROM, which is about as basic as it gets. The problem with this is that the translation uses the much more complex mapper 68 (and for what other than expanded storage, I'm not entirely sure).
My PRG and CHR chips are regular W27C020-70 EEPROMs, in a 32 pin DIP. I've already programmed them based on the translated rom, that shouldn't be a problem (assuming it's written so it can run on a real console, that is).
I've already acquired Maharaja, which uses the same mapper as the translation, seems to use the same mirroring, and has a CHR and PRG just like Portopia uses. The PRG is 28 pins, however, and I don't know how to connect my 32 pin EEPROM to it. Is it the same pins as on MMC3 cartridges? Can I just stick the CHR in as is since it's 32 pin? The game also has a battery, which portopia doesn't use, and I'm not sure if I can just remove it. I figure it's probably also a good idea to replace the 22uf electrolytic capacitor on it since it's pretty old if this works.
I was mainly wondering if this would even be possible to do (I haven't seen anyone's finished repro of the game yet) and if so, what modifications I'd need to make.
Thanks a lot for reading this.