Bosch BMP280 Digital Pressure Sensor. More...

#include <BMP280.h>

Public Types
enum	BMP280_REG_map_t { BMP280_READID = 0x58 , BMP280_ID = 0xD0, BMP280_CALIB25 = 0xA1, BMP280_CALIB00 = 0x88 }
typedef union BMP280::bmp280_config_reg	bmp280_config_t
	CTRL_MEAS (0xF4)
typedef union BMP280::bmp280_ctrl_meas	bmp280_ctrl_meas_t
	STATUS (0xF3)
typedef union BMP280::bmp280_status	bmp280_status_t
	RESET (0xE0)
Public Member Functions
	BMP280 (PinName sda, PinName scl, int slaveAddress)
	BMP280 constructor.
	BMP280 (I2C *i2c, int slaveAddress)
	BMP280 constructor.
int	writeReg (char reg, char value)
	Write a device register.
int	readReg (char reg, char *value)
	Read a device register.
	BMP280 (PinName sda, PinName scl)
	BMP280 constructor.
	BMP280 (I2C *i2c)
	BMP280 constructor.
	~BMP280 (void)
	BMP280 destructor.
int	init (bmp280_osrs_P_t Osrs_p, bmp280_osrs_T_t Osrs_t, bmp280_FILT_t Filter, bmp280_MODE_t Mode, bmp280_TSB_t T_sb)
	This initializes the BMP280.
int	ReadCompData (float Temp_degC, float Press_Pa)
	The BMP280 has 2 modes.
int	reg_write (BMP280_REG_map_t reg, char value)
	This function allows writing to a register.
int	reg_read (BMP280_REG_map_t reg, char *value, char number)
	This function allows writing to a register.
void	Reset (void)
	Performs a soft reset on the BMP280.
int	Detect (void)
	Detects if the BMP280 is present.
float	compensate_T_float (int32_t adc_T)
	Performs calculations on the raw temperature data to convert to.
float	compensate_P_float (int32_t adc_P)
	Performs calculations on the raw pressure data to convert to.
int	Sleep (void)
	Puts the BMP280 in low power Sleep mode.
int	ReadCompDataRaw (char *bmp280_rawData)
	This reads the raw BMP280 data.
int	ReadCompDataRaw2 (char *bmp280_rawData)
	This reads the raw BMP280 data uses the Bosch algorithm to get the data.
void	ToFloat (char bmp280_rawData, float Temp_degC, float *Press_Pa)
	This converts the raw BMP280 data to couble based on Bosch's algorithm.
float	ToFahrenheit (float temperature)
	converts to Farenhite from Centigrade
int	ReadId (void)
	Reads a unique ID from the register.
Data Fields
char	bmp280_reset
	ID (0xD0)
uint16_t	dig_T1
	Unique temp coeffs. read from the chip.
uint16_t	dig_P1
	Unique Press. coeffs. read from the chip.
int32_t	t_fine
	This is calculated int the temperature to be used by the pressure.

Detailed Description

Bosch BMP280 Digital Pressure Sensor.

Definition at line 45 of file BMP280.h.

Member Typedef Documentation

typedef union BMP280::bmp280_config_reg bmp280_config_t

CTRL_MEAS (0xF4)

typedef union BMP280::bmp280_ctrl_meas bmp280_ctrl_meas_t

STATUS (0xF3)

typedef union BMP280::bmp280_status bmp280_status_t

RESET (0xE0)

Member Enumeration Documentation

enum BMP280_REG_map_t

Enumerator:

BMP280_READID	BMP280 Register addresses.
BMP280_ID	calib25-calib00: 0xA1-0x88
BMP280_CALIB25	Beginning address.
BMP280_CALIB00	Ending address.

Definition at line 49 of file BMP280.h.

Constructor & Destructor Documentation

BMP280	(	PinName	sda,
		PinName	scl,
		int	slaveAddress
	)

BMP280 constructor.

Parameters:

sda	mbed pin to use for SDA line of I2C interface.
scl	mbed pin to use for SCL line of I2C interface.
slaveAddress	Slave Address of the device.

Definition at line 37 of file BMP280.cpp.

BMP280	(	I2C *	i2c,
		int	slaveAddress
	)

BMP280 constructor.

Parameters:

i2c	I2C object to use.
slaveAddress	Slave Address of the device.

Definition at line 45 of file BMP280.cpp.

BMP280	(	PinName	sda,
		PinName	scl
	)

BMP280 constructor.

Parameters:

sda	mbed pin to use for SDA line of I2C interface.
scl	mbed pin to use for SCL line of I2C interface.

BMP280 ( I2C * i2c )

BMP280 constructor.

Parameters:

i2c	I2C object to use.

~BMP280 ( void )

BMP280 destructor.

Definition at line 57 of file BMP280.cpp.

Member Function Documentation

float compensate_P_float ( int32_t adc_P )

Performs calculations on the raw pressure data to convert to.

pressure in Pascal, based on Bosch's algorithm

Parameters:

adc_P Raw Press ADC value, Global dig_P1, dig_P2,..., dig_P9

Returns:: The Pressure in Pascals

Definition at line 292 of file BMP280.cpp.

float compensate_T_float ( int32_t adc_T )

Performs calculations on the raw temperature data to convert to.

temperature in deg C, based on Bosch's algorithm

Parameters:

Raw	Temp ADC value, Global dig_T1, dig_T2, dig_T3

Returns:: The Temperature in deg C

Definition at line 274 of file BMP280.cpp.

int Detect ( void )

Detects if the BMP280 is present.

Parameters:

none

Returns:: 1 for found, 0 for not found, -1 for comm error

Definition at line 252 of file BMP280.cpp.

int init	(	BMP280::bmp280_osrs_P_t	Osrs_p,
		BMP280::bmp280_osrs_T_t	Osrs_t,
		BMP280::bmp280_FILT_t	Filter,
		BMP280::bmp280_MODE_t	Mode,
		BMP280::bmp280_TSB_t	T_sb
	)

This initializes the BMP280.

The BMP280 has 2 modes. FORCED mode and NORMAL mode. FORCED Mode gives more control to the processor as the processor sends out the Mode to initiate a conversion and a data is sent out then. NORMAL mode is initialized once and it just runs and sends out data at a programmed timed interval. (In this example the main() will set this to Normal function)

Parameters:

Osrs_p-	Pressure oversampling
Osrs_t-	Temperature oversampling
Filter-	Filter Settings
Mode-	Power Modes
T_sb-	Standby time (used with Normal mode)
dig_T1,dig_T2,dig_T3-	Coeffs used for temp conversion - GLOBAL variables (output)
dig_P1,....,dig_P9-	Coeffs used for press conversion - GLOBAL variables (output)

Returns:: 0-if no error. A non-zero value indicates an error.

Read all the temp coeffecients from the BMP280 memory. It will be used in calculation

Read all the press coeffecients from the BMP280 memory. It will be used in calculation

Definition at line 65 of file BMP280.cpp.

int ReadCompData	(	float *	Temp_degC,
		float *	Press_Pa
	)

The BMP280 has 2 modes.

FORCED mode and NORMAL mode. FORCED Mode gives more control to the processor as the processor sends out the Mode to initiate a conversion and a data is sent out then. NORMAL mode is initialized once and it just runs and sends out data at a programmed timed interval. (In this example the main() will set this to Normal function)

Parameters:

*Temp_degC	- Pointer to temperature (result in deg C)
*Press_Pa	- Pointer to pressure (resul in Pascal)

Returns:: 0-if no error. A non-zero value indicates an error.

Definition at line 189 of file BMP280.cpp.

int ReadCompDataRaw ( char * bmp280_rawData )

This reads the raw BMP280 data.

Parameters:

*bmp280_rawData- array of raw output data

Returns:: 0-if no error. A non-zero value indicates an error.

Definition at line 167 of file BMP280.cpp.

int ReadCompDataRaw2 ( char * bmp280_rawData )

This reads the raw BMP280 data uses the Bosch algorithm to get the data.

in float, then the float gets converted to an String

Parameters:

*bmp280_rawData- array of raw output data

Returns:: 0-if no error. A non-zero value indicates an error.

Definition at line 148 of file BMP280.cpp.

int ReadId ( void )

Reads a unique ID from the register.

Parameters:

none

Returns:: The correct id value which is 0x58

Definition at line 265 of file BMP280.cpp.

int readReg	(	char	reg,
		char *	value
	)

Read a device register.

CONFIG_REG (0xF5)

int reg_read	(	BMP280_REG_map_t	reg,
		char *	value,
		char	number
	)

This function allows writing to a register.

reg- Address of the register to read from (input) *value- Pointer to the value read from the register (output)

Returns:: 0-if no error. A non-zero value indicates an error.

Definition at line 213 of file BMP280.cpp.

int reg_write	(	BMP280_REG_map_t	reg,
		char	value
	)

This function allows writing to a register.

Parameters:

reg-	Address of the register to write to
value-	Data written to the register

Returns:: 0-if no error. A non-zero value indicates an error.

Definition at line 201 of file BMP280.cpp.

void Reset ( void )

Performs a soft reset on the BMP280.

Parameters:

none

Returns:: none

Definition at line 246 of file BMP280.cpp.

int Sleep ( void )

Puts the BMP280 in low power Sleep mode.

Parameters:

none

Returns:: 0 if no errors, -1 if error.

Definition at line 230 of file BMP280.cpp.

float ToFahrenheit ( float temperature )

converts to Farenhite from Centigrade

Parameters:

temperature in Centigrade

Returns:: temperature value in Farenhite

Definition at line 142 of file BMP280.cpp.

void ToFloat	(	char *	bmp280_rawData,
		float *	Temp_degC,
		float *	Press_Pa
	)

This converts the raw BMP280 data to couble based on Bosch's algorithm.

Parameters:

*bmp280_rawData-	array of raw input data
*Temp_degC-	pointer to output, Temp value in deg C
*Press_Pa-	pointer to output, Press value in Pascals

Returns:: 0-if no error. A non-zero value indicates an error.

Definition at line 176 of file BMP280.cpp.

int writeReg	(	char	reg,
		char	value
	)

Write a device register.

Field Documentation

char bmp280_reset

ID (0xD0)

Definition at line 142 of file BMP280.h.

uint16_t dig_P1

Unique Press. coeffs. read from the chip.

Definition at line 195 of file BMP280.h.

uint16_t dig_T1

Unique temp coeffs. read from the chip.

Definition at line 191 of file BMP280.h.

int32_t t_fine

This is calculated int the temperature to be used by the pressure.

Definition at line 205 of file BMP280.h.

Type:	Program
Mbed OS support:	Mbed OS
Created:	25 Oct 2016
Imports:	1381
Forks:	1
Commits:	4
Dependents:	0
Dependencies:	1
Followers:	128

BMP280 Class Reference

Public Types

Public Member Functions

Data Fields

Detailed Description

Member Typedef Documentation

Member Enumeration Documentation

Constructor & Destructor Documentation

Member Function Documentation

Field Documentation

Repository toolbox

Repository details

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BMP280 Class Reference

Public Types

Public Member Functions

Data Fields

Detailed Description

Member Typedef Documentation

Member Enumeration Documentation

Constructor & Destructor Documentation

Member Function Documentation

Field Documentation

Repository toolbox

Repository details

Important Information for this Arm website

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