Connect to a compatible USB device and detect it on the browser. Check lsusb on Linux or system_profiler SPUSBDataType on MacOSX for Vendor ID and Product ID.
<label for="vendorId">Vendor ID: 0x</label>
<input type="text" name="vendorId" placeholder="vendorId" id="vendor" value="2a03">
<p><a href="#" id="click">Click me to get USB device info</a></p>
<script>
  click.onclick = function() {
    var vendorId = '0x' + document.getElementById('vendor').value
    navigator.usb.requestDevice({ filters: [
      { 'vendorId': vendorId }
    ] })
    .then(device => {
      console.log(device)
      console.log("Product ID: " + device.productId.toString(16))
      console.log("Vendor ID: " + device.vendorId.toString(16))
    })
    .catch(error => { console.log(error) })
  }
</script>