A HomeKit Thermostat. It requires a compatible sensor.

The following configuration is available for thermostats:

{
  "c":{"t":3},
  "a":[{
    "t":25,
    "w":3,
    "p":"HPDRAGAAAGCKAE",
    "s":5,
    "g":14,
    "0":{"i":[{"c":"BcAbBaAbBaBbAbAdArAdCdBdAuHaDcDbDaU"}]},
    "1":{"i":[{"c":"BcAbBaAbBaBbAbAdApAbAbAgBdAuFaBaBaGbDaU"}]},
    "2":{"i":[{"c":"BcAbBaAbBaBbAbAdApAaAdCdBdAuFaAaDcDbDaU"}]},
    "3":{"i":[{"c":"BcAbBaAbBaBbAbAdApAbAdBdBdAuFaBaDbDbDaU"}]},
    "4":{"i":[{"c":"BcAbBaAbBaBbAbAdApAaAcBfBdAuFaAaCbFbDaU"}]},
    "5":{"a":0}
  }]
}

This is an example of a Mitsubishi HVAC IrDA Remote Thermostat and Humidity sensor ("t":25). The type ("w":3) is a heater & cooler thermostat. The thermostat is controlled via a infra-red and the protocol is defined by "p":"HPDRAGAAAGCKAE". A sensor is connected to GPIO 14 ("g":14) and is is the default type 2 ("n":2 not required as the default). Control of the sensor is via actions 0 to 5 and their respective IR strings. The initial state has been set to "last state before restart" ("s":5).

Multiple actions are supported by a thermostat. The Digital Outputs "r": [{}] for each should be configured to attain the desired state.

Sensor GPIO is defined by the "g" key contained within the accessory object.

Home Accessory Architect only supports one-wire temperature sensors. This is a mandatory option that specifies the GPIO the sensor is attached to e.g. "g": 14

Sensor type is defined by the "n" key contained within the accessory object.

A variety of one-wire sensors are available and supported by HAA.

Refer to Sensor Type for details of the sensors that are supported.

Sensor polling time is defined by the "j" key contained within the accessory object.

The thermostat temperature is polled on a regular basis to read the latest values. These values are then posted to HomeKit. If this option is not specified then the sensor will be polled once every 30 seconds.

Temperature offset is defined by the "z" key contained within the accessory object.

The accuracy of the temperature sensor varies and may sometimes read consistently higher or lower than the actual temperature. The temperature offset option enables calibration of the sensor by specifying a positive or negative offset to apply to the reading.

The option uses is a floating point value, accurate to 1 decimal place e.g. 1.1

Humidity offset is defined by the "h" key contained within the accessory object.

NOTE: This option is available only for device type 25

The accuracy of the available one-wire sensors varies and may sometimes read consistently higher or lower than the actual humidity. The humidity offset option enables calibration of the sensor by specifying a positive or negative offset to apply to the reading.

The option uses is a floating point value, accurate to 1 decimal place e.g. 1.1

Thermostat type is defined by the "w" key contained within the accessory object.

This option is used to select the type of thermostat controlled by the device.

Minimum temperature is defined by the "m" key contained within the accessory object.

This option is used to set the minimum temperature in °C you can set. The value is a floating point variable accurate to 2 decimal places e.g. 10.04.

Maximum temperature is defined by the "x" key contained within the accessory object.

This option is used to set the maximum temperature in °C you can set. The value is a floating point variable accurate to 2 decimal places e.g. 10.04.

Deadband temperature is defined by the "d" key contained within the accessory object.

The "d" option is used to set the temperature deadband in °C to adjust how thermostat works. The value is a floating point variable accurate to 2 decimal places e.g. 10.04.

A thermostat deadband (or hysteresis) is designed to lag the inputs from the environment for the purposes of saving you energy and saving your air conditioner or furnace wear and tear from turning on and off frequently.

The deadband represents a temperature range around the automatic mode set point that is your “comfort zone”. For example, with a 4°C wide deadband ("d": 4.0) and a setpoint of 20°C, the deadband will be 18 - 22°C. This keeps the system from bouncing quickly between heating and cooling when in automatic mode.

When temperatures fall within the deadband, neither heating nor cooling can occur. A larger deadband will have your system run more economically, while a smaller deadband will have your system hold the temperature closer to the setpoint and increase comfort. The deadband does not affect your thermostat’s operation when in HEAT or COOL modes.

Example: If you have an 8ºC deadband and you set your desired temperature to 22ºC in AUTO mode, your heating set point will be 18º and your cooling set point will be 26ºC.

Deadband temperature force idle is defined by the "df" key contained within the accessory object.

Deadband temperature soft on is defined by the "ds" key contained within the accessory object.

The list of notifications "m" supported by a thermostat are as follows:

See the general Accessory Notifications section for details of how to configure these notifications.

Digital Inputs "b" are supported by this accessory.

See Digital Inputs for details on how to define this mandatory option.

State inputs "f[n]" & Status Inputs "g[n]" are supported by this accessory. The supported list is:

NOTE: Fixed states "f5", "f6" & "f7" are only available when thermostat type 3 is selected ("w": 3)

Refer to State Inputs for more detail and examples.

ICMP Ping inputs "p[n]" and "q[n]" are supported by this accessory. Refer to ICMP Ping Inputs for more detail.

Wildcard Actions "y[n]" are supported by this accessory. The supported list is:

Refer to Wildcard Actions for more detail.

The Initial State key is supported by this accessory. Refer to Initial State for more details.