RJ-45 MC Cthulhu+ IMP+ Xbox 360 Dual Mod Tutorial Diagram

Thanks rtdzign! (And thanks to hikarutilmitt for the good intentions.) I just finished rewiring my TE and it’s working awesome. I know people have explained how to wire both the 360 & MC Cthulhu to the RJ-45, but having a diagram makes everything so unambiguous.

Also, I thought I read that the MC Cthulhu had to be the Primary on the Imp, so I’m glad you made it clear that it doesn’t. It’s a bit more convenient for me having the 360 Primary. Speaking of which…

To have your SE/TE stick work like Kreeee’s, you have to wire the MC Cthulhu to 2 D+ and 2 D- on the Imp, and wire the 360 PCB to 1 D+ and 1 D- on the Imp. The pictured diagram in Step 2 does it the other way around, but notes that it can be switched. You’d also have to connect the Imp’s Guide point to the RS point on the 360 PCB, instead of connecting it the way it is in this guide. Bomberman’s guide has images that show how to do this with both the SE and TE.

Diagrams halfway down.


I used 26 gauge stranded and have 10 colors of wire used to help color code. I cut all of my wires to size first. I strip off maybe 5mm to a 1cm of wire, tin it, insert through hole, solder in, cut excess, then move on to the next hole. After all holes on MC cthulhu are done, I then wrap it in a wire sleeve and use my multimeter to test what wire is what. The color codes I used help me figure out what wire is what. I cut to proper size, strip tin then solder them to the xbox 360 pad. After each point bridged I do a second continuity check to make sure it is right before moving on.


Follow this tutorial but do the following differently:

1 - Swap D+/D- around on the imp so the 360 is on the “1” channel
2 - Wire the guide on the imp to the RS switch

It’s much more elegant this way imo.

Finally thoroughly took a look at this, well done… it’s a pretty slick ass way to allow for only 1 port. Using the Imp as a passthrough for the 2 required lines during MC functionality is a very sweet way to do things.

I likes that a LOT…I may be using that fairly soon. Good shit man!

Has everyone nominated this post?

RTDZIGN deserves serious recognition for this…it’s really about time someone did this.

I can’t stress enough how helpful abd well written this is, and can’t help but think that I had some part in this.

I PM’d RT asking questions about the mod, prior to this posting…I guess he got sick of my questions and wrote this :slight_smile:


Someone needs to STICKY this thread…but anyway…


Everyone…do it!

Chuckles If I was going to answer you I figure I might as well do it right and do it for everyone.

If you look at Kyle’s Sticky Read first tutorials/ thread in the tutorials section, he actually listed it there. He made a tutorials sticky because there where too many stickies to the point where the first page was more than half stickies.

Yeah a lot of people kept asking about this on the forums, and I recently sold networkingyuppy some ethernet hacked cables and was worried he might hook it up wrong. It was something I’ve wanted to do for a while so having these folks asking on how to do it prompted me to write it.

Updated with info for DPDT switch option if you do not want to use an Imp.

Thank you so much for this guide. This is exactly what I’ve been looking for.

i have a few questions about the piggy back method.

  1. i have a regular madcatz xbox pad do i have to solder the buttons and d pad to certain points on the MC cthulhu??
    or do i just solder away and the board detects the points??

  2. is it better to use the IMP or the DPDT switch method?

3.if you can can you put up what wire goes to what spot on the MC cthulhu.

thanks man!

  1. Look to 3. For regular Madcatz tutorial look at Upas’ Madcatz padhacking tutorial.. Instead of putting the button signals to the button switches you solder those to the unlabeled points.

  2. Reasons listed in first post. It is about whether or not you can drill a hole in your case to mount the switch.

  3. Comes with MC Cthulhu. Any drawing I make would be too messy or too much work.

Wouldn’t wiring the 360 as primary on the imp cause you to have to hold down the guide button in order to play on ps2 (and any other system that uses either the D or E line on the mc)?

I don’t understand the significance of wiring the RJ-45 cable to the Imp at all.

Yeap, that is why Cthulhu is recommended as primary unless you do 70%-90% of your gaming on xbox 360. You actually have to press guide for any system that uses the Cthulhu.

This is needed to allow USB to work. The D+ and D- lines are data lines for USB. If you want one USB cable port to work for 360 and PS3/PC, you need the imp or dpdt swtich to prevent data from both boards going to the system of choice at the same time.

If you notice the D+ and D- both come off the Cthulhu and and 360 pad. The imp chooses one set of data lines to be out put to the console. The output of that goes to the RJ-45 cable. While both boards are on the output data. Imagine that the xbox D+D_ lines speak English and the PS3 speaks Japanese to the console. If you don’t separate them the system simultaneously gets english and japanese letters for both those lines and the communcation makes no sense. Imp chooses one or the other.

Oh all right. Thanks. I didn’t install a Neutrik USB port on mine since when I did the RJ-45 mod I had a MC Cthulhu in there already for 360/PS3. The RJ-45 was only for custom cables.

Is there any reason why the VCC and Ground lines aren’t wired to the IMP instead of the Cthulhu?

They wired in step 3. You might be do it either way since VCC are all have the same continuity and Common Ground does too.

But then for option b with a dpdt switch, it makes writing a tutorial more complicated, and I have not tested wiring the VCC to the imp directly.

The reason I’m asking is that I’m trying to accomplish something similar. Only I didn’t have room to fit a RJ45 connector to my case so I went with CAT5 cable with a DIN connector at the end. Connecting the stick with that cable does absolutely nothing at the moment, not even the USB ding and a failure. Connecting the Cthulhu with a USB cable however works just fine and everything worked with the IMP before I rewired it to fit my new cable scheme. I guess I’ll have to hook it up and bust out the multimeter.

I’m experiencing a similar problem. The usb cable connects the MC Cthulhu just fine, but the RJ-45 jack gives nothing, nor will it hop over to 360 mode. After checking the continuity between the D+ , D- wires and the keyjack pinout, i have to say something gets muddled somewhere around the imp

Usually if you can figure out how to take pictures with the macro on, people often will look over any wiring problems you may have. Sometimes D+ and D- might be shorting each other out. Check all adjacent soldering spots for continuity with a multimeter. There is a possibility that something is linked that should not.

Ok, i’m going to figure that out somehow. For the sake of helping others, should I reply info here, or onto the Main Cthulhu thread?