Double check your wiring, don’t trust other peoples color guides, especially on 3rd party cables.
It could be your adapter. Only good way to test out NES and SNES cables are on the actual consoles. Original hardware is preferred but clone hardware consoles works too.
If you are going to use your MC Cthulhu on your PC, stick to USB.
lol man i KNEW you were gonna say exactly that. I should have prefaced my statement with “yes i always pin out every wire myself”
As for the USB adapter im only using that on the NES (I have an actual SNES), and yeah i thought the adapter was the problem too but, when my friend tried it on his NES he said it didnt work on there either. Also for some strange reason, i got a different result using both a PS360 board and MC Cthuhlhu board with usb to NES. Neither worked but PS360 didnt read at all, the MC Cthuhlu atleast gave me “incorrect” inputs"
So i take it there arent any weird quirks about making NES or SNES cables?
Like with the PS360+ and the Saturn/ jumper to home terminal fix
I couldn’t make correct SNES/NES cables either, although I made several PS2/ Xbox/ Saturn/ USB/ etc with no problem.
I wondered if there was some issue with version of console: US versus Europe vs Asia … I had the same issue with PCE cables…
Did you try updating the MCC firmware ?
NES/SNES controllers are about as straight forwards as it gets. The encoder chip is just a Shift register, which is pretty basic.
Pal Region SNES consoles did have a region lock on the controller ports.
There is a minor hack to fix this.
What you do is open up your SNES, find the controller board inside, and ether bypass these 4 diodes or remove them and replace them with wire.
US game pads work on Japanese consoles and vise versa.
yeah thats weird then. im not doing anything weird with it.
im just using a regular old SNES mini
EDIT
Alright so further testing and it looks like some weird shit is going on with it. i can only get 4 buttons to work. LK MK start and select.
the weird thing is when i press home, then i can use LP MP but they are also now LK MK…but with turbo. so like double buttons in each row
none of the other buttons work no matter what i i do
when i press home again, they deactivate EXCEPT if i push them simultaneously, Then they together become a start button. What the hell is going on here. Does the MC Cthulhu have a built in toggle switch or something?
its strange because this problem ONLY occurs on SNES. My sticks are fine on EVERY other console.
anyway im thinking i’ll sac a few more cables and see if that changes anything. if that doesnt work i’ll just redo these. if that doesnt work then…i dont know.
Alright i made a couple more cables and its looks like i got it.
gonna redo the other ones and see what the heck went wrong there.
damn now i have new set of problems.
so i recently sold off one my mc modded arcade sticks and the sent it back saying it had problems. obviously that doesnt make a whole lot of sense since its my stick and i know for you it works. well now i have it in my hands and it rj45 does not work at all anymore.
i tried using usb and that works perfectly fine. all the buttons and directions are good. i redid the firmware and still nothing.
i even recrimped a new rj45 connector for the inside. still nothing. im gonna hit it with a multimeter but i get the feeling the connection is good.
now before i crank out the soldering iron and start to redo stuff, are there some quick things i can test or do to get this working. are there any known problems with this sort of thing?
Are you using a panel mount RJ plug on the case like a Neutrik?
yes. im using a typical neutrik pass through adapter
Probe the cable coming from the board. Then probe the solder points on the back of the Neutrik with the inside cable plugged in. Count the beeps. Both should be the same. If not, you need a new Neutrik.
its definitely not the neutrik. i plugged it up to another one and it was the same. hopefully its just the cable and a redoing it will solve it.
so i swapped out both the old cthulhu and the old neutrik adapter.
its looking like it was the neutrik adapter causing the problem or possibly both because the old adapter doesnt work with either boards and the old cthulhu board doesnt agree with either adapter.
its weird for it fail suddenly after all these years.
RJ45 connectors aren’t really made for repeated connects and disconnects.
i understand that but of all the sticks to fail, this one shouldnt have been one of them. i can probably count how many times i used this one.
my main 2 sticks are still going strong
edit: maybe its the fact that i hardly ever used it is the actual reason why it failed?
I didn’t find this info already in this thread, although maybe it’s buried somewhere, and also could not find it despite multiple searches online.
To pinout an RJ-45 connector for use on SNES and MC Cthulhu:
SNES Chthulhu RJ-45 Color
1 G 1 Brown
4 C 4 Red
5 F 7 Orange
6 A 2 Yellow
7 V 8 White
Or, simply, SNES cable colors to RJ-45
RJ-45 SNES
1 Brown
2 Yellow
4 Red
7 Orange
8 White
I would not quote any colors matches, even if those colors are right for you, they could be wrong for someone else.
I have found Nintendo branded controllers that didn’t follow the normal color assignments.
Its best to go off Pin assignments and figure out your own color guide.
Hence why the Original guide at the beginning of this thread never gave color to pin match ups.
I found going by the actual assignments is a better guide
http://pinoutguide.com/Game/snescontroller_pinout.shtml
As you see from that link that Red and Yellow are often swap around.
Worst offenders is Sony controllers. With Wire colors changing with each batch of production.
No one should be cutting cables without using a multimeter, it is your best friend.
I’ve even seen some fucked up USB cables where the colours were all switched around.
I got a USB cable where the colors were Yellow, Blue, Brown, and Red. And Red was not VCC.
That’s fucking disgusting, mines were purple, blue, white, and red iirc and white wasn’t D- and red wasn’t VCC, LMAO. This is why DMMs are the best so you’ll be prepared for matchups like these.
Good points. I thought about that as I was posting, but figured someone would call me out on it if it would be an issue. 
Nonetheless, hopefully the correlation to the RJ-45 pins is helpful. That wasn’t noted in the original post, and was probably the biggest head scratcher of the effort.
Also worth mentioning that SNES wiring does not simply slide or stab into an RJ-45 connector like most other cables I’ve created. It took a bit of finagling and jimmy-rigging with various fine-point edged “tools” that I had at my immediate disposal. The individual cables don’t all extend to the end of the RJ-45 head like I would like, but they are in far enough for contact to be made once crimped and the cable to works.