For a hobby project using the stm32f1xx-hal, I'm wanting to periodically read a sensor and then push the values such that I can graph them realtime in a webUSB app.
I have found an example in webusb_blinky by mvirkkunen which demonstrates the connectivity portion, but it's not clear to me how I would adapt it to publish sensor values. Should I be overriding control_in?
Any suggestions/help would be appreciated. Thanks!
You could define a control transfer that requested the device respond with the current sensor values but the more natural USB mechanism for publishing sensor updates is with an IN endpoint.
The usbd-serial module is the best example I can find of creating and using endpoints with this framework. A serial port consists of both an IN and OUT endpoint for bidirectional streaming of data. For your application you would only need the IN endpoint since the device only generates data.