No, unfortunately you cannot charge the XOOM with a USB cable.

Just about every device with a microUSB connection uses the port for syncing data and charging the device’s internal battery.  But the Motorola XOOM is different.

To charge the XOOM, you’ll need either a XOOM-specific wall or car charger that uses the tablet’s small, round charging port, or a dock that can charge the tablet using the two gold-colored contacts on the bottom edge of the XOOM. 

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