/**************************************************************************** *                   I.MX6 简单电路模拟USB设备的插入 * 说明： *     因为USB这边出了点问题，于是撘一个简单的电路来测试一下。 * *                                          2016-7-28 深圳 南山平山村 曾剑锋 ***************************************************************************/一、参考文档：    搭个简单电路验证USB主机是如何检测USB设备的插入和拨出动作的        http://usb.baiheee.com/usb_article/usb_spec/usb_plug_detect.html二、测试效果如图：    usb 2-1.1: new full speed USB device number 3 using fsl-ehci    usb 2-1.1: device descriptor read/64, error -32    usb 2-1.1: device descriptor read/64, error -32    usb 2-1.1: new full speed USB device number 4 using fsl-ehci    usb 2-1.1: device descriptor read/64, error -32    usb 2-1.1: device descriptor read/64, error -32    usb 2-1.1: new full speed USB device number 5 using fsl-ehci    usb 2-1.1: device not accepting address 5, error -32    usb 2-1.1: new full speed USB device number 6 using fsl-ehci    usb 2-1.1: device not accepting address 6, error -32    hub 2-1:1.0: unable to enumerate USB device on port 1三、洞洞板焊接如图：