jimmy jiang <jiangyuqing@...> writes: More information: If I connect one USB2.0 hub between the port(only USB port in the embedded system) and the USB flash stick, I am able to copy the file from other places to the USB flash. However, the connection between the USB flash and the USB host controller will be lost after couple minutes. Thanks. Regards Jimmy -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html