Linking to an account¶

Linking is a one-time procedure: the device gets a one-time pairing token, exchanges it on the portal for a permanent secret and saves the secret to NVS. After that it connects to the portal on its own after every reboot. Until it has a secret, the device is in setup mode and waits for a token.

In the iDryer app¶

The device is on the network (see Wi-Fi), the phone is on the same network.
Connect a new device → the Pairing step (if the device is already on the network, tap the step's chip at the top of the window) → Pair.
The app finds the device on the local network, gets a token from the portal, hands it to the device and waits until the portal confirms that the device is online.
After Device paired, the device is in the list on the portal and in the app.

The log before pairing:

[BOOT] WiFi ok, logs enabled
[INFO ] CLOUD: WiFi connected, IP: 192.168.1.42, RSSI: -55 dBm, …
…
[INFO ] CLOUD: binding-v3: no secret — awaiting pairing token (SETUP)

After:

[INFO ] CLOUD: binding-v3: pairing token received (… chars)
[INFO ] CLOUD: binding-v3: activating with pairing token (serial=DEVICE_… mcu=-)
[INFO ] CLOUD: binding-v3: activated, deviceId=… -> Ready
…
[INFO ] MQTT: Connected! …

The firmware web installer passes the token over USB with the PAIR_TOKEN command (see below).

Unlinking¶

Unlinking in the app or on the portal reaches the device as the revoke command. Every firmware needs the handler:

// Unlinking in the app or on the portal: erase the secret and wait for new pairing.
s_link.onCommand("revoke", [](JsonObjectConst) { s_link.handleRevoke(); });

handleRevoke() erases the secret and keeps the network: the device waits for pairing again. Without the handler the secret stays in the device, and it can be linked again only after WIPE_IDENTITY.

USB commands¶

After joining the network, the core accepts lines on the serial port (115200, each line ends with a newline):

Command	Reply	What it does
`STATUS`	`STATUS:state=… wifi=… ip=… cloud=… serial=… mcu=… fw=… part=…`	state: `state` is `bound` (linked) or `setup` (waiting for a token), `cloud` is `online`/`offline`
`WIPE_IDENTITY`	`WIPE_IDENTITY:OK`	erases the secret like `revoke`; the network stays
`PAIR_TOKEN:<token>`	`PAIR_TOKEN:OK`, `PAIR_TOKEN:ERROR`, `PAIR_TOKEN:ERROR:ALREADY_BOUND`	passes a pairing token; a linked device does not accept a token

STATUS
STATUS:state=setup wifi=1 ip=192.168.1.42 cloud=offline serial=DEVICE_… mcu=- fw=0.1.0 part=…

Before the device joins the network, the port is busy with Improv and the commands do not answer. In a build with IDRYER_DEV_REPL the port belongs to the product and these commands do not exist: see Detailed setup.

If it did not work¶

the app does not find the device: the phone and the device are on the same network; guest networks often block device discovery;
PAIR_TOKEN:ERROR:ALREADY_BOUND, or the device belongs to another account: unlink it on the portal or send WIPE_IDENTITY, then pair again.

Next¶

Telemetry.