原帖由： BurnieG ,
Usually you need a compatible OTG cable or dock for your device. An OTG cable is different than a normal USB cable. An OTG cable has the sense pin shorted to the ground pin, while a normal USB cable does not. Some manufactures may use a resistor of a certain value to short the sense pin to the ground pin. This tells the device to enter USB host mode when an OTG cable is connected. So if you have a compatible OTG cable you should only need to plug in the cable for the device to activate USB host mode (OTG). Plug in your USB device to the OTG cable first then plug the OTG cable into your tablet. If this does not work then you may want to let me know what version of Android you are running and what kernel it uses. You can find this information in the settings menu under About tablet. Or you can do a search to see if the kernel you are using has OTG function or not included. I am going to guess your kernel does have it but it may not hurt to check if you can not get the tablet to enter USB host mode(OTG). There are also some apps from the Google Play Store that may help troubleshoot your OTG issue, just type OTG into Google Play search to find some. Hope this helps.