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View Full Version : Wierd issue with SNES Game Genie.


stardust4ever
03-15-2018, 12:17 AM
I think my Game Genie has a stuck bit. I've haven't touched it in a couple years but I never had issues with it in the past. Last time I used it was on stock hardware, to grant infinite lives while playing the physical cart of Guntz's SML v3 Super Mario World hack, and enabling the feather cape to reach some hard to reach spots. Recently the Super NT gave me a renewed interest in everything Super Nintendo related, and I have run into so problems with the device itself.

Anyway I made a youtube video of the behavior.

https://youtu.be/2oD4tFCKICU

Basically the third character on the code input screen entry appears to have a stuck bit in it. Upon reset, some codes entered have the wrong character assigned, and they still don't work properly when entered. It exhibits the same behavior on stock hardware as well as the Super NT.

Is there potential to fix it, or should I just buy another one? *_*
jb143
03-15-2018, 12:55 AM
That is...odd. I expected to see some consistent pattern if some of the bits were open or shorted.

As always, I'd start by cleaning the contacts with q-tips and alcohol just to rule that out. My first thoughts were that an open or short trace on the PCB could cause it to happen but I don't really know.
stardust4ever
03-15-2018, 01:17 AM
That is...odd. I expected to see some consistent pattern if some of the bits were open or shorted.

As always, I'd start by cleaning the contacts with q-tips and alcohol just to rule that out. My first thoughts were that an open or short trace on the PCB could cause it to happen but I don't really know.Well each character is 4 bits. Eight characters revert to a different character while the other eight stay the same. I'm aware that Genies aren't straight hex code as the bit order is obfuscated. But it seems obvious to me that one of the address bits in the third column is stuck. This means potentially half of all codes will not work as expected. I'm curious if anyone else has experienced a Game Genie malfunction in this fashion, and if it's bit rot of the rom or a stuck bit in ram.
jb143
03-15-2018, 10:31 AM
Yeah, I was wondering if it the odd pattern was because it wasn't using a standard hex mapping. I would still suspect dirty contacts or a broken trace over bit rot or something internal to the chip, unless they used really really cheap chips which is certainly a possibilty. Maybe there's a cold solder join on one of the pins.
gbpxl
03-15-2018, 02:16 PM
not sure. Usually if something in life is too hard i just give up and move on to something else instead of trying to make it easier