Virtual Barometric Pressure/Altimeter Sensor Interface. More...

Public Attributes
bool(*	readPressure )(uint32_t *const pressure)
	Read the current pressure from the device. More...

bool(*	readAltitude )(int32_t *const altitude)
	Get the current altitude, corrected for Sea Level Pressure. More...

void(*	setSeaLevelPressure )(uint32_t slp)
	Set the sea level pressure. More...

Detailed Description

Virtual Barometric Pressure/Altimeter Sensor Interface.

A standard interface for a device which can measure barometric pressure.

This is a simple interface, which only provides the ability to read the current sample.

Fundamental Assumptions

The device produces barometric pressure readings
- This device reports barometric pressure in hectopascal (hPa)
- The reported barometric pressure reading will be compensated for ambient temperature by the implementation if it is required.
- Pressure will be formatted as a 32-bit fixed-point integer with format UQ22.10, giving a resolution of 0.001 hPa.
This device produces barometric altitude readings
- This device will report barometric altitude in meters
- Altitude will be formatted as a 32-bit fixed-point integer with format Q21.10, giving a resolution of 0.001 m.
- Altitude will be corrected for Sea Level Pressure. If no value for SLP has been supplied, calculations will assume 1013.25 hPa.
The device will indicate whether the current sample is valid or invalid
This interface, at its core, appears to be blocking. However, you can still implement this interface in a non-blocking way. For example, you could always return the most recent altitude measurement, while there is another thread (or a timer) that handles updates to that measurement asynchronously.

Definition at line 68 of file barometric_sensor.h.

bool(* BarometricSensor::readAltitude) (int32_t *const altitude)

Get the current altitude, corrected for Sea Level Pressure.

If no value for SLP has been supplied, calculations will assume 1013.25 hPa.

Precondition: The pressure sensor has been properly initialized by the system.; The altitude parameter is not NULL.

Postcondition: If the measurement is valid, the data pointed to by the altitude parameter will be updated with the latest reading.; If the measurement is invalid, the data pointed to by the altitude parameter will remain unchanged.

Returns: Current altitude in meters (m), corrected for sea level pressure. Altitude is specified as a signed 32-bit fixed-point number in format Q21.10.

Definition at line 104 of file barometric_sensor.h.

bool(* BarometricSensor::readPressure) (uint32_t *const pressure)

Read the current pressure from the device.

Precondition: The pressure sensor has been properly initialized by the system.; The pressure parameter is not NULL.

Postcondition: If the measurement is valid, the data pointed to by the pressure parameter will be updated with the latest reading.; If the measurement is invalid, the data pointed to by the pressure parameter will remain unchanged.

Parameters

[in,out] pressure Pointer which will be used for storing the latest pressure reading. This pointer must not be null.

Pressure will be formatted as a 32-bit fixed-point integer with format UQ22.10, giving a resolution of 0.001 hPa.

Returns: True if the sample is valid, false if invalid (e.g., an error occured)

Definition at line 88 of file barometric_sensor.h.

void(* BarometricSensor::setSeaLevelPressure) (uint32_t slp)

Set the sea level pressure.

Parameters

[in] slp The current sea level pressure in hPa. slp should be specified as an unsigned 32-bit fixed-point number in format UQ22.10.

Definition at line 111 of file barometric_sensor.h.

The documentation for this struct was generated from the following file: