HID descriptor

RE: HID descriptor

Hung Bui — Tue, 20 Jun 2017 10:32:48 GMT

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.

RE: HID descriptor

yoshimura — Mon, 19 Jun 2017 07:14:10 GMT

Hi Hung, thanks for taking time to answer the questions. The example is really helpful. Wondering what 0x81, 0x02 // Input (Data,Value,Relative,Bit Field) Stands for here. I guess this is more general description table question. After looking up USB HID Usage table, for consumer control devices zoom in/out are mapped to 22D/E/F, so I guess, I can append new fields to the description like this?

RE: HID descriptor

Hung Bui — Thu, 18 May 2017 13:06:38 GMT

Yes, it's an option. I'm not sure if there is actually a way to send a key to change zoom level besides the volume buttons.

RE: HID descriptor

yoshimura — Thu, 18 May 2017 06:35:18 GMT

Hi Hung, if I understand correctly, I should be able to remap volume keys action on the phone to emulate zoom in/out actions?

RE: HID descriptor

Hung Bui — Mon, 15 May 2017 10:45:17 GMT

Hi Yoshimura,

Would it's possible to map zoom functioning to the volume button on the phone ? Here is one example from my coworker on how to configure HID report as Consumer Control and send the volume keys. Pressing button 3 will send a volume up and button 4 volume down