UPM

The UPM API is a high level sensor library for IoT devices using MRAA. See examples here. Back to index page.
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HDXXVXTA Class

Module: hdxxvxta

The driver was developed using the HD2NVSTA1 humidity transmitter. The 'T' variant supports a temperature transmitter as well. Both signals are provided by the device as analog 0-5Vdc or 0-10Vdc outputs. The A1 variant supports a temperature range of -40C-50C, while the A2 variant supports a range of 0C-50C. Humidity ranges for all devices in this device family range from 0% to 100% (non-condensing).
This driver used the 5Vdc outputs for obvious reasons. Your MCU must be configured for 5V operation. Using any other analog reference voltage will require the appropriate external circuitry (such as a voltage divider) in order to interface safely with your MCU.
For devices which do not support temperature, use '-1' as the temperature pin number in the object constructor. If temperature measurement is disabled, getTemperature() will always return 0C/32F.

Methods

HDXXVXTA

(
  • hPin
  • tPin
  • aref
)
Number

HDXXVXTA object constructor

Parameters:

  • hPin Number

    Analog pin to use for the humidity measurement

  • tPin Number

    Analog pin to use for temperature. If your device does not support temperature, use -1 as the value so that temperature will not be queried and an analog pin won't be wasted.

  • aref Number

    The analog reference voltage, default 5.0

Returns:

Number:

setRange

(
  • range
)

Set the temperature range of the sensor. HDA1 sensors support a range of -40C-50C, while HDA2 devices support a temperature range of 0C-50C. The constructor sets a default of RANGE_MINUS40_50.

Parameters:

  • range RANGE_T

    One of the RANGE_T values, default is RANGE_MINUS40_50

update

()

Read current values from the sensor and update internal stored values. This method must be called prior to querying any values, such as temperature or humidity.

getTemperature

(
  • fahrenheit
)
Number

Get the current temperature. update() must have been called prior to calling this method. If temperature measurement was disabled (by passing -1 as the temperature pin in the constructor) then this function will always return 0C/32F.

Parameters:

  • fahrenheit Boolean

    true to return the temperature in degrees fahrenheit, false to return the temperature in degrees celsius. The default is false (degrees Celsius).

Returns:

Number:

The last temperature reading in Celsius or Fahrenheit

getHumidity

() Number

Get the current relative humidity. update() must have been called prior to calling this method.

Returns:

Number:

The last humidity reading

Properties

RANGE_MINUS40_50

Enum RANGE_T

RANGE_0_50

Enum RANGE_T