Connectivity Status
The HMI Device State service tracks whether each HMI Device is active or inactive and updates a set of server-side attributes (or time-series) with connection timestamps. This lets you build automations — notifications, alarms, dashboard indicators — that react to HMI Devices going offline or coming back online.
HMI Device State Data
Section titled “HMI Device State Data”When a HMI Device connects, disconnects, or becomes inactive, iRis Cloud updates the following values:
| Field | Type | Description |
|---|---|---|
active | Boolean | true if the HMI Device is currently active |
lastConnectTime | ms since epoch | When the HMI Device last connected |
lastDisconnectTime | ms since epoch | When the HMI Device last disconnected |
lastActivityTime | ms since epoch | When the HMI Device last sent telemetry, attributes, or an RPC command |
inactivityAlarmTime | ms since epoch | When the last inactivity event was fired |
Connectivity Events
Section titled “Connectivity Events”The HMI Device State service tracks four connectivity event types while updating HMI Device state.
| Event | When it fires |
|---|---|
| Connect | HMI Device establishes a session (MQTT) |
| Disconnect | HMI Device session closes (MQTT) |
| Activity | An inactive HMI Device sends telemetry, updates attributes, or sends an RPC command |
| Inactivity | No activity received |
Inactivity Detection
Section titled “Inactivity Detection”A HMI Device is marked inactive when no activity is received for 60 seconds. iRis Cloud checks all HMI Devices on a schedule controlled by 60 seconds.