Ambient Pressure Sensing shared. More...

#include "sarmfsw.h"
#include "I2C_component.h"

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Macros
#define	SEA_LEVEL_PRESSURE 1013.25f
	Average sea level pressure (hPa / mbar)

Functions
float	Get_SeaLevel_Pressure (void)
	Sea Level pressure getter (in hPa / mbar)

float	Atmospheric_Pressure_To_Altitude (const float pressure, const float sea_level_pressure)
	Calculates the altitude (in meters) using international barometric formula from the specified atmospheric pressure (in hPa / mbar), and sea-level pressure (in hPa / mbar).

float	Altitude_To_SeaLevel_Pressure (const float pressure, const float altitude)
	Calculates the pressure at sea level (in hPa / mbar) using international barometric formula from the specified altitude (in meters), and atmospheric pressure (in hPa / mbar).

Detailed Description

Ambient Pressure Sensing shared.

Author: SMFSW

Copyright: MIT (c) 2017-2026, SMFSW

Macro Definition Documentation

◆ SEA_LEVEL_PRESSURE

#define SEA_LEVEL_PRESSURE 1013.25f

Average sea level pressure (hPa / mbar)

Note: Define SEA_LEVEL_PRESSURE to use a custom average SeaLevel pressure value (hard value); It is highly recommended to implement Get_SeaLevel_Pressure function in project instead.

Function Documentation

◆ Altitude_To_SeaLevel_Pressure()

float Altitude_To_SeaLevel_Pressure	(	const float	pressure,
		const float	altitude )

Calculates the pressure at sea level (in hPa / mbar) using international barometric formula from the specified altitude (in meters), and atmospheric pressure (in hPa / mbar).

!

Note: A difference in altitude of ∆altitude = 10m corresponds to 1.2hPa pressure change at sea level

Parameters

[in]	pressure	- Atmospheric pressure in hPa / mbar
[in]	altitude	- Altitude in meters

Returns: Sea Level pressure estimation in hPa / mbar

◆ Atmospheric_Pressure_To_Altitude()

float Atmospheric_Pressure_To_Altitude	(	const float	pressure,
		const float	sea_level_pressure )

Calculates the altitude (in meters) using international barometric formula from the specified atmospheric pressure (in hPa / mbar), and sea-level pressure (in hPa / mbar).

!

Note: A pressure change of ∆p = 1hPa corresponds to 8.43m at sea level

Parameters

[in]	pressure	- Atmospheric pressure in hPa / mbar
[in]	sea_level_pressure	- Sea Level pressure in hPa / mbar

Returns: Altitude in meters

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◆ Get_SeaLevel_Pressure()

float Get_SeaLevel_Pressure ( void )

Sea Level pressure getter (in hPa / mbar)

!

Weak Functions: Get_SeaLevel_Pressure is recommended to be user implemented (average value returned by weak implementation)

Returns: Sea Level pressure in hPa/mbar