HID descriptor

[yoshimura]

Hello,

I am using HID mouse/keyboard examples from SDK to learn creating custom HID device.

Besides using four buttons on EVK to simulate motion action. I would love sending zooming in/out actions from custom devices to android devices. I realize I would need to understand HID or generic USB descriptor protocol to create proper descriptor table.

However, after going through multiple online examples, I am still struggling to find a understandable tutorials or specs (e.g.www.usb.org/.../Hut1_12v2.pdf) to create a custom descriptor table based on hardware configuration.

How are the hex values determined? Would it matter to use different type of devices defined in usb spec such as digitizer, mouse, desktop or etc...

Thank you! I really appreciate your input.

[Hung Bui]

Hi Yoshimura-san, 0x81, 0x02 describe the input report, is a data (not constant), variable (not array), relative (not absolute) and is bit field as they are boolean. There is a tutorial here that you can have a look.

Regarding the zoom in/out descriptor you pointed to, I believe it's to zoom in and out on the GUI screen, not to zoom in and out the camera. You need to check with Android.