POC: demo one device controlling another

[mitra42]

• Actuator Relay #54

• Sensor_SHT85 measuring humidity and temp

• Two devices - one with relay, other with sensor

• Build an adapter to demo the relay - box, Mains plug & socket, maybe 5V power supply, ESP8266 Relay

• control_xxx to watch humidity exceed certain level and send a message

  • MQTT high level: way to direct an activity to a topic, plus way to discover #43
  • configuration of control to subscribe to humidity (from same device)
  • configuration of that control to send message to a certain other device B/relay
    • Advertisement that specifies a value wants to know a digital topic to connect to
  • Slider control for humidity level
  • Expand slider control to give hysteresis (fatter bar) - maybe cursor turns into vertical line

• HTML control to select a topic to configure from digital outputs

• Test that it all works together.

• Future

  • Add controls over input i,e. not hard-wired to humidity
  • MQTT high level: way to direct an activity to a topic, plus way to discover #43 - completion: genericize control_demo_mqtt to have controllable input / output / setpoint and as template/class