Apps: radio link micro:bit reconnect failure

[microbit-robert]

It seems possible to get the radio link micro:bit into a bad state with the following steps:

• Follow the connection flow for radio
• Once successfully connected, unplug the radio link micro:bit
• A reconnect / try again dialog appears
• Replug the radio link micro:bit
• Dismiss the dialog by clicking the close buttons or background overlay
• Click connect at the bottom of the page, this restarts the connection flow 'from scratch'
• Sometimes the connection to the data collection micro:bit will fail, but unplugging and replugging will fix it
• The radio link micro:bit connection will almost certainly fail
• Sometimes unplugging and replugging will fix this sometimes it won't
• The LEDs on the radio link micro:bit show a single solid dot (not flashing) when this failure occurs

The live behaviour is that clicking connect at the bottom of the page after dismissing the try again / reconnect dialog retries the connection to the radio link micro:bit rather than starting from scratch.

Issue is a work in progress. More details to follow.

• Can it be recovered - yes sometimes, after a random(?) number retries and a mix of unplug/replug and just clicking "try again"
• Does it flash before the connection fails?

[microbit-robert]

Trace after unplugging and replugging radio link micro:bit prior to trying to connect (browser permissions dialog is shown):

Event {"type":"WebUSB-info","message":"connected"}
index-5w5jGsTR.js:20816 Detected board ID 9904
index-5w5jGsTR.js:20816 Event {"type":"WebUSB-info","message":"board-id/9904"}
index-5w5jGsTR.js:20816 Event {"type":"WebUSB-info","message":"board-family-hic/36029796990b"}
index-5w5jGsTR.js:20816 Starting serial
index-5w5jGsTR.js:20816 USB connection status CONNECTED
index-5w5jGsTR.js:20816 Stopping serial before flash
index-5w5jGsTR.js:20816 Reconnecting before flash
index-5w5jGsTR.js:20816 An error occurred whilst attempting to use WebUSB.
index-5w5jGsTR.js:20816 Details of the error can be found below, and may be useful when trying to replicate and debug the error.
index-5w5jGsTR.js:20816 InvalidStateError: Failed to execute 'transferOut' on 'USBDevice': The device must be opened first.
    at t.<anonymous> (index-5w5jGsTR.js:409:37467)
    at index-5w5jGsTR.js:409:1629
    at Object.next (index-5w5jGsTR.js:409:1734)
    at index-5w5jGsTR.js:409:671
    at new Promise (<anonymous>)
    at kt (index-5w5jGsTR.js:409:422)
    at t.write (index-5w5jGsTR.js:409:37231)
    at e.<anonymous> (index-5w5jGsTR.js:409:8754)
    at index-5w5jGsTR.js:409:1629
    at Object.next (index-5w5jGsTR.js:409:1734)
index-5w5jGsTR.js:20816 USB connection status DISCONNECTED
index-5w5jGsTR.js:20816 Radio connection status DISCONNECTED
index-5w5jGsTR.js:20816 Event {"type":"WebUSB-error","message":"11/failed-to-execute-transferout-on-usbdevice-the-device-must-be-opened-first"}

Trace after simply clicking try again (browser permissions dialog not shown):

An error occurred whilst attempting to use WebUSB.
index-5w5jGsTR.js:20816 Details of the error can be found below, and may be useful when trying to replicate and debug the error.
index-5w5jGsTR.js:20816 InvalidStateError: Failed to execute 'transferOut' on 'USBDevice': The device must be opened first.
    at t.<anonymous> (index-5w5jGsTR.js:409:37467)
    at index-5w5jGsTR.js:409:1629
    at Object.next (index-5w5jGsTR.js:409:1734)
    at index-5w5jGsTR.js:409:671
    at new Promise (<anonymous>)
    at kt (index-5w5jGsTR.js:409:422)
    at t.write (index-5w5jGsTR.js:409:37231)
    at e.<anonymous> (index-5w5jGsTR.js:409:8754)
    at index-5w5jGsTR.js:409:1629
    at Object.next (index-5w5jGsTR.js:409:1734)
index-5w5jGsTR.js:20816 USB connection status DISCONNECTED
index-5w5jGsTR.js:20816 Radio connection status DISCONNECTED
index-5w5jGsTR.js:20816 Event {"type":"WebUSB-error","message":"11/failed-to-execute-transferout-on-usbdevice-the-device-must-be-opened-first"}

Trace after simply clicking try again a second time (browser permissions dialog not shown):

An error occurred whilst attempting to use WebUSB.
index-5w5jGsTR.js:20816 Details of the error can be found below, and may be useful when trying to replicate and debug the error.
index-5w5jGsTR.js:20816 Error: Bad response for 8 -> 17
    at e.<anonymous> (index-5w5jGsTR.js:409:8858)
    at index-5w5jGsTR.js:409:1629
    at Object.next (index-5w5jGsTR.js:409:1734)
    at o (index-5w5jGsTR.js:409:478)
index-5w5jGsTR.js:20816 USB connection status DISCONNECTED
index-5w5jGsTR.js:20816 Radio connection status DISCONNECTED
index-5w5jGsTR.js:20816 Event {"type":"WebUSB-error","message":"undefined/bad-response-for-8-17"}

This eventually connected after another unplug / replug, fail, try again without unplugging and replugging. So it is recoverable, but as a user I would have given up or refreshed the page long before this.