[AT&T, Rogers HTC One X, Telstra One XL] ModemJunki:
*** Another update ***

The 4.2.2 firmware appears to be missing the desktop dock mode entirely. The phone does not go into landscape mode and no dock launches.

*** Another update ***

The 2.2.1 firmware appears to be missing the desktop dock mode entirely. The phone goes into landscape mode but no dock launches.

Nothing I can fix, sorry.

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*** IMPORTANT UPDATE ***

It has been brought to my attention that this may only work for the US version of the HOX, and not for the international (quad core) version.

See this post in the thread: http://xdaforums.com/showpost.php?p=35485317&postcount=20

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So, after getting used to my Thunderbolt having a nice HTC dock that triggers Desktop mode, I was very disappointed to find nothing yet on the market for the AT&T One X. instead of returning the inexpensive dock, or messing around with software, I rolled up my sleeves and made it happen.

Originally I started making a breakout connection for the USB thinking I'd build a powered bluetooth speaker into the dock but then I realized I had too many projects going on. That's why the tiny breadboard is in the pictures - its part of the abandoned breakout. It's not needed at all, you could safely tape or heatshrink these 1/4 watt resistors for this application.

Also I realized after I started splicing that I needed to pare back more of the insulation, if I had to do it again I'd give myself more room to work with.

In my particular dock, the cable shield is not connected to port shield but it is used as the ground.

Pin 5 (ground) cable shield / black

Pin 4 (ID) Black wire

Pin 3 (Data +) Yellow

Pin 2 (Data -) White

Pin 1 (+5V DC) Red

The signal to go into dock mode is triggered with a resistor between pins 4 and 5.

10kOhm triggers auto dock mode

68kOhm triggers desk dock mode (also, a 47kOhm triggers desk dock mode)

Starting in Car Dock mode allows a toggle to Desk Dock with the switch, but the phone doesn't toggle back to the Car Dock from Desk Dock when switched back.

Not the point, at any rate - the only reason I did this was because I had the two-pole switch and both resistors handy.

The dock:

The underbelly (pull off the rubber feet gently)..

If you don't pull off the feet, you won't get the hidden screws.

The top will come off easily. Now you can push the bottom out.

The bottom has a steel weight.

Gently pry the cable out of the base. It lifts out.

Now you can unscrew the other end.

This is how I tested the resistors. Be VERY careful if you do this - the pin can break the wire. For such a tiny wire you need to pierce the side of the insulation.

Proof of concept.

I actually only had a 68.1kOhm resistor handy, it works fine.

Tie the ends of the resistors together to the shield. Tie the center of the switch to the ID wire.

Shrink wrap, tape, or otherwise insulate the connections. TEST FIRST, then reassemble - install switch....

Put it all back together....

Fullsize pics here:

https://picasaweb.google.com/ModemJunki/OneXDockHack#

See it in action! (not sure how to embed YouTube properly...)

http://youtu.be/tZ0Mom1wZq4

[YOUTUBE]http://www.youtube.com/watch?v=tZ0Mom1wZq4[/YOUTUBE]