UsbMode is an Android application for investigating USB charging, hosting and keyboard functions.
The top pane indicates details over charging. The bottom pane indicates details over keyboards. The "Linux code" is the scancode that is seen by the Android subsystem. The "Android code" is the keycode as translated by the Android subsystem. The "HID usage" is a conjecture of what USB HID Usage Page:Usage might have caused the keycode. In many cases there is no one-to-one mapping. The "Inputs" field is dependent on whether /sys (the SysFS) is readable.
The "View USB" pane will display the tree of hosted USB peripherals, provided that there is hosting capability, that it is readable and that there are peripherals.
The Barnes & Noble Glowlights do not switch painlessly into USB host mode. A small daemon has been written to enable UsbMode to control host/peripheral mode without UsbMode having root capability.
Download UsbMode-2.4.apk
Download the usbhostd daemon