Alternate or better description for finding power on the usb cable end:

First: Find the power wire.

Connect USB cable to USB host of your computer.
Connect a multimeters ground cable to your USB host computers ground. The metal parts on the rear will usually do.
Use your multimeter with at least 6V DC range to find the wire with 5 Volt (mine did 5,3V). This is the power wire.

Second: Find ground wire.

Set your multimeter to diode, beep, or short circuit test mode (Please edit this mode to the correct english name). The one that makes it beep if you put the test probes together.
Test the remaining 3 wires for short circuit. The one continuesly beeping is ground.

Third: Identify Tx and Rx.

The remaining two did a very short beep directly after touching with the probes, but stay silent then.
They are Tx and Rx, follow the steps on article to find out which is which.

Double7 23:26, 28 August 2010 (UTC)

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