TI中文支持网我的板子（beaglebone black）用自带的usb线，连接pc (ubuntu 14.04)【3.16.0-33-generic #44~14.04.1-Ubuntu SMP】。
用beaglebone black自带的系统（emmc）启动后，pc能够正确识别网卡和boot分区。
板子下电，按住boot键，没有插sd卡，用usb线连接pc，无法识别usb设备。
这样我无法使用uniflash工具烧写系统阿，求教各位了～
shen liu3：
dmesg打印：usb 3-7: new full-speed USB device number 115 using xhci_hcd usb 3-7: not running at top speed; connect to a high speed hub usb 3-7: Dual-Role OTG device on non-HNP port usb 3-7: can't set HNP mode: -32 usb 3-7: new full-speed USB device number 116 using xhci_hcd usb 3-7: not running at top speed; connect to a high speed hub usb 3-7: Dual-Role OTG device on non-HNP port usb 3-7: can't set HNP mode: -32 usb 3-7: new full-speed USB device number 117 using xhci_hcd usb 3-7: not running at top speed; connect to a high speed hub usb 3-7: Dual-Role OTG device on non-HNP port usb 3-7: can't set HNP mode: -32 usb 3-7: new full-speed USB device number 118 using xhci_hcd usb 3-7: not running at top speed; connect to a high speed hub usb 3-7: Dual-Role OTG device on non-HNP port usb 3-7: can't set HNP mode: -32 usb usb3-port7: unable to enumerate USB device
