How to Install an Xbox1 Cable Onto a Multi-Console Cthulhu

This Instructable will guide you through installing an original Xbox (Xbox1) style controller cable onto a multi-console 'MC' Cthulhu.

All of the information about the Cthulhu project is available online in the Shoryuken.com forums:
http://forums.shoryuken.com/showthread.php?t=162026

Please be quite aware that this Instructable applies only to the MC Cthulhu; if your Cthulhu was purchased advertised only for PS3/PC use, then you cannot add ax Xbox cable and expect it to work. Upgrade chips are available if you would like to turn your PS3 Only Cthulhu into an MC Cthulhu. If you are unsure which one you have, plug your arcade stick into your computer with the Start and Select buttons held down. if you see a new device called 'Cthulhu Bootloader' get installed, you have an MC Cthulhu. If you only see your arcade stick show up as normal, then it is not an MC Cthulhu.

Step 1: Step 1: Don't

This may sound rather odd, but don't. Step 1 of the my 'How to Install an Xbox cable on an MC Cthulhu' is 'Don't do it.'

Chances are you already have a USB cable being used by the Cthulhu, the same one used for playing on a PC or PS3. The Xbox1 uses USB for it's controllers; it just has an oddball end to make things difficult.

You can easily find adapters like the one pictured below on ebay for under $10. With one of these adapters, you can use your existing USB cable through the adapter on your Xbox1. All without having to even open the case. Remember to look for one with a female USB end!

The rest of the instructions will detail the process of installing an Xbox cable into the MC Cthulhu like normal, but if you can avoid the unneeded soldering, you should.

Step 2: Get to Know Your Xbox1 Cable

The Xbox1 controllers work over USB, but with an addition wire we don't need to worry about (some say it's a 12v power line, others say its for a vsync line for use with lightguns. Either way, we don't need it.) and very oddball connector.

The pinout numbers listed below are not a misprint; they are actually numbered that way. The very nice thing about Xbox1 cables is that every cable I've seen actually uses a set color code for the wires. You should of course use a multimeter to verify, but the Xbox1 connector is usually safe enough to just work off of the wire colors.

Here's the important list:
Pin # - Color - Purpose - Cthulhu Column
1 - Red - VCC - V
2 - White - "USB D-" - D
3 - Green - "USB D+" - E
4 - Black - Ground - G
5 - Yellow - Not Used - Not Connected

Strip off 3-4 cm of insulation off of the end of the cable to expose the wires. There will likely be some additional shielding wire; in the extension cable shown below, there is an aluminum foil-type material covering all of the wires, along with a few uninsulated copper wires. Trim those back close to the end of the insulation.

Remove about 1-2mm of insulation off of the end of the wires that are left. Use your multimeter to check for continuity between the exposed wire end and one of the pins on the Xbox1 end. Verify the pinout of the five remaining wires and write down which color goes to what pin, along with the listed purpose and the Cthulhu column it will go into.

Once you've identified which wire (usually Yellow) that goes to pin #5, go ahead and clip it short next to the cable insulation.

If you have any head shrink tubing, now would be good time to slide it over the cable and out of the way so we don't forget it later.

Step 3: Prepare the Wires

This is a quick step, but very recommended to help make things go smoother. Tin your wires.

The easiest way I've found to accomplish this is to twist the copper wires together so you have no stragglers, then apply a little flux onto the exposed copper at the end of each wire. Melt a little solder on the end of your iron, and touch it to your wire. With the flux, the wire will drink up the solder, leaving a much easier to use and solder single piece to solder to the board, instead of multiple thin copper threads. The insulation on the wire will melt and retract a little bit; that will actually help make things easier when we solder.

Step 4: Know Where It Is Going.

Below is an image of the grid on the Cthulhu board where the console cables all get soldered to.

Unlike the Playstation, we have no restriction on which row we use. If it recommended you don't use the first row, in case you decide to add a Playstation cable, but feel free to use row 2 or row 3, whichever you feel might be easiest. If you are certain you will never want to add a Playstation cable, then feel free to use row 1, but I see no reason to limit your future options when row 2 or 3 works just as well.

We have four wires in the Xbox cable, and four specific spots where they should go.

Pin # - Color - Purpose - Cthulhu Column
1 - Red - VCC - V
2 - White - "USB D-" - D
3 - Green - "USB D+" - E
4 - Black - Ground - G

The wires are tinned, we know which wires does what and where on the board it should go. Let's get to it.

Step 5: Soldering

Four wires, four holes, four soldering points. Easy.

I recommend starting and one end and working your way individually to the other. I start with the G column, would through A-F, and finally V, left-to right.

Take the GND wire, place it through the row 1 column G hole so the insulation stops at the board. Take a finger, bend the wire over from underneath and hold it in place while you flip the board over. Solder the wire in place, and trim off any excess wire.

Repeat down the same row for each wire in turn.

Step 6: Final Clean-Up and Test

The most important thing you can do is trust your instincts. If anything looks or feels wrong, fix it.

Next, test anyways to prevent any catastrophic problems. The worst thing you can do is accidentally cause a short. Use your multimeter to check for continuity between the VCC screw terminal (top right-most screw terminal in the picture below) and a GND terminal (like the lower left-most terminal) If there is a low resistance present, you MUST fix it before even thinking about testing the board out. It would be very dangerous to plug it into anything without locating the short and fixing it. The ground and power lines in the columns you just soldered to are very far apart, so this sort of mistake will be rare, but it is better to test for it now.

If you used heat shrink tubing, slide it down over the wires as far as you can, and use a heat source such as a heat gun, or even a lighter, to shrink it down over the wires.

A note on final installation: The cable is secured to the board with only the four very thin wires. In the event of even slight force, these wires will not hold. It is very important when installing in your arcade stick that you devise some method of strain relief, so any tugging on the cable will be stopped and not result in pressure on these small wires. The usual method I prefer is to make a small loop in the cable, secure the loop with a zip tie, and making sure the loop is as close to the exit of the case as possible. If the cable gets tugged at all, the loop is far too big to exit the case, preventing the thin wires from being pulled.

Give it a test, and enoy your stick with a good Xbox game!