HID Generic In/Out

A USB HID device that exchanges raw IN/OUT reports over a vendor-defined usage page, with no standard keyboard/mouse usage. It simply echoes back whatever the host sends.

What it does

Presents one HID interface built from the generic in/out report descriptor template (vendor usage page), with both an IN and an OUT endpoint.
Whenever the host sends data on the OUT endpoint (or via SET_REPORT), the device echoes the same bytes back to the host via tud_hid_report.
The LED blinks to indicate USB state (250 ms not mounted, 1000 ms mounted, 2500 ms suspended).
Because the reports carry no standard HID usage, the device is meant to be driven by a host-side tool rather than recognized as a keyboard/mouse. The example ships with hid_test.js (node-hid) and hid_test.py (Python hid) scripts to send and receive data.

USB Descriptors

Interface	Class driver
0	HID (generic in/out, raw vendor reports)

Configuration

Notable tusb_config.h settings:

#define CFG_TUD_HID            1
#define CFG_TUD_HID_EP_BUFSIZE 64

Building

CMake:

mkdir build && cd build
cmake -DBOARD=raspberry_pi_pico ..
cmake --build .

Make:

make BOARD=raspberry_pi_pico all

Try it

After flashing, run the bundled host tool — node hid_test.js or python3 hid_test.py — to send a buffer to the device and observe the same data echoed back.