Hello, everybody
Recently I tried to do conversion of my Japanese Chrono Trigger with the support of 27C322 and two multiplexers which I bought from a person who makes repros and I assume everything was written fine.
I tried to follow this scheme by Mousebite Labs which he used for making an adapter
But after soldering it turned out that game does not work, it boots, but fails each time differently, sometimes after a minute, sometimes after five minutes. Firstly artifacts appear, then game freezes and gets stuck. Also it doesn't boot again right after that but if cartridge lays for a while without powering, only then it can boot again.
Maybe someone can kindly help with the issue? I've seen someone put OE signal to MAD chip, but it isn't described in scheme. I would appreciate any help
27C322 Eng Rom to Japanese Chrono Trigger Failed
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1. NO BLATANT PIRACY. This includes reproducing homebrew less than 10 years old, with the exception of free software.
2. No advertising your reproductions, with the exception of free software.
3. Be nice. See RFC 1855 if you aren't sure what this means.
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Re: 27C322 Eng Rom to Japanese Chrono Trigger Failed
I think you need to connect the chip enable lines to the rom.
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Re: 27C322 Eng Rom to Japanese Chrono Trigger Failed
27c322 pin 11 to maskrom 24 (assuming it uses 36pins)
you have that pin grounded in your schematic.
you have that pin grounded in your schematic.
Re: 27C322 Eng Rom to Japanese Chrono Trigger Failed
Ultimately, the multiplexer chips /enable is what needs to be controlled. Turning the rom “off” won’t really help if the multiplexers are still driving. So really, the rom can be enabled all the time like your schematic shows because the signals won’t get through the mux’s if they are controlled correctlyyour_sunset wrote: ↑Thu Mar 16, 2023 7:06 amCould you please tell to which ROM pin do I need to connect the line?
Are you hand wiring this?
Drawing that blue circle around the mask rom makes it difficult to actually see where you connected some of the lines. Not helpful. You can just reference the “mask rom” and we would understand, no circle needed. Lastly, the mask rom /CE (pin 24) should probably go to the 27c322 rom /CE. The maskrom /OE (pin 33) probably the mux’s enable pin. It’s hard to tell but that may be the way you have it already.
Edit: according to the mouse labs chart, it said to connect the /CE as I mentioned
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- Posts: 4
- Joined: Tue Mar 14, 2023 10:08 am
Re: 27C322 Eng Rom to Japanese Chrono Trigger Failed
Here's the schematic I used when soldering Yes, this is handwiredMarkfrizb wrote: ↑Thu Mar 16, 2023 2:20 pmUltimately, the multiplexer chips /enable is what needs to be controlled. Turning the rom “off” won’t really help if the multiplexers are still driving. So really, the rom can be enabled all the time like your schematic shows because the signals won’t get through the mux’s if they are controlled correctlyyour_sunset wrote: ↑Thu Mar 16, 2023 7:06 amCould you please tell to which ROM pin do I need to connect the line?
Are you hand wiring this?
Drawing that blue circle around the mask rom makes it difficult to actually see where you connected some of the lines. Not helpful. You can just reference the “mask rom” and we would understand, no circle needed. Lastly, the mask rom /CE (pin 24) should probably go to the 27c322 rom /CE. The maskrom /OE (pin 33) probably the mux’s enable pin. It’s hard to tell but that may be the way you have it already.
Edit: according to the mouse labs chart, it said to connect the /CE as I mentioned
E2BB502F-8BAB-4531-A05F-1AFB29627733.jpeg