ePaper Boards

Flash the firmware once (USB to bc1). Default secrets.h with no WiFi defines is fine — the device will provision itself.
Power the board on. The e-paper shows SETUP MODE with the SSID it just created (e.g. HexworthBoard-A1B2).
On your phone, join that WiFi network. A captive-portal page opens automatically (or browse to http://192.168.4.1).
Pick your home WiFi from the list, enter the password, and type a Board ID (lowercase + dashes, e.g. room-318). Submit.
Device saves to its internal flash (NVS), reboots, joins your WiFi, and starts polling its Cloud Function URL.
Back here in the admin UI, click + New Board and create a Firestore doc with the same Board ID. Fill in the courses to display.

At power-on, hold the BOOT button on the XIAO for 5 seconds. The device wipes its saved credentials and reopens the captive portal.
Then follow the onboarding flow from step 2 above.
This is also how you change the Board ID — re-pair and enter a different one.

The Board ID lives in two places: the device's NVS storage and the Firestore doc here. They must match exactly.
The device appends it to the CF URL: ?board=room-214. The CF looks up /epaper_boards/room-214 and renders accordingly.
If the doc doesn't exist, the device gets HTTP 404 and the display keeps its last image. Create the doc here to fix.
Once a board is in the wild, do not change its ID in the admin UI — the device won't follow. Either re-pair the device or keep both in sync.

OK Last seen under 30 minutes ago — healthy, on its regular polling cycle.
Stale Last seen 30 min – 4 hours ago. Probably OK but worth checking if it persists.
Dead No contact for 4+ hours. Likely powered off, WiFi lost, or hardware fault.

Devices poll their CF every 15 minutes by default (compiled into firmware).
Edits saved here take effect on the device's next poll — up to 15 min lag. Press the device's RESET button to pull immediately.
The e-paper retains its last image even when power is lost, so there's no "blank" failure mode.

Registered Boards