WebUSB
For a deeper dive into the WebUSB, refer to https://developers.google.com/web/updates/2016/03/access-usb-devices-on-the-web
WebUSB API Specification: https://wicg.github.io/webusb/
Overview
This simple echo application demonstrates the WebUSB sample application. This application receives the data and echoes back to the WebUSB based web application (web page) running in the browser at host. This application is intended for testing purposes only. For running real usecase, implement applications based on the WebUSB API. This sample can be found under samples/subsys/usb/webusb in the Zephyr project tree.
Requirements
This project requires an USB device driver, which is available for multiple boards supported in Zephyr.
Building and Running
Build and flash webusb sample with:
west build -b <board to use> samples/subsys/usb/webusb
west flash
Testing with the latest Google Chrome on host
This sample application requires the latest Google Chrome, a web page based on WebUSB API to connect to the USB device and optionally http server running on localhost to serve the web page.
WebUSB is a powerful new feature added to the Web and it is available only to secure origins. This means the web page/site that is used to connect to the device must be served over a secure connection (HTTPS).
Follow these steps to run the demo on your host system:
Run the latest Google Chrome on host.
Implement a web app (web page) using WebUSB API and run it on localhost.
The sample can be found in the webusb sample directory: samples/subsys/usb/webusb/index.html.
This sample web page demonstrates how to create and use a WebUSB interface, as well as demonstrate the communication between browser and WebUSB enabled device.
There are two ways to access this sample page:
Using Chrome browser go to WebUSB HTML Demo App
Host the demo page locally: Start a web server in the webusb sample directory.
$ python -m http.server
Using Chrome browser open url http://localhost:8001/
Connect the board to your host.
Once the device is booted, you should see a notification from Chrome: “Go to localhost to connect.”. Click on the notification to open demo page. Note that at the moment WebUSB landing page notification is disabled in Chrome on Windows. See https://github.com/WICG/webusb#implementation-status
Click on the Connect button to connect to the device.
Send some text to the device by clicking on the Send button. The demo app will receive the same text from the device and display it in the text area.