Manuel Caballero / HTU21D

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HTU21D Class Reference
Public Types | Public Member Functions

HTU21D Class Reference

Example: More...

#include <HTU21D.h>

Public Types

enum  HTU21D_address_t
 

DEFAULT ADDRESSES.

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enum  HTU21D_user_register_resolution_t { RESOLUTION_12RH_14TEMP = 0, RESOLUTION_8RH_12TEMP = 1, RESOLUTION_10RH_13TEMP = 2, RESOLUTION_11RH_11TEMP = 3 }
 

RESOLUTION.

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enum  HTU21D_user_register_status_t { STATUS_END_BATTERY_HIGH_2V25 = 0, STATUS_END_BATTERY_LOW_2V25 = 1 }
 

STATUS: END OF BATTERY.

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enum  HTU21D_user_register_heater_t { HEATER_ENABLED = 0, HEATER_DISABLED = 1 }
 

ON-CHIP HEATER.

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enum  HTU21D_user_register_otp_t { OTP_ENABLED = 0, OTP_DISABLED = 1 }
 

OTP RELOAD.

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enum  HTU21D_master_mode_t { MODE_HOLD_MASTER = 0, MODE_NO_HOLD_MASTER = 1 }
 

MODE.

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enum  HTU21D_status_t { , I2C_SUCCESS = 0 }
 

INTERNAL CONSTANTS.

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Public Member Functions

 HTU21D (PinName sda, PinName scl, uint32_t addr, uint32_t freq)
 Create an HTU21D object connected to the specified I2C pins.
 ~HTU21D ()
 Delete HTU21D object.
HTU21D_status_t HTU21D_Init (HTU21D_master_mode_t myMode, HTU21D_user_register_resolution_t myResolution, HTU21D_user_register_heater_t myHeater)
 It configures the device.
HTU21D_status_t HTU21D_SoftReset (void)
 It resets the device by software.
HTU21D_status_t HTU21D_TriggerTemperature (void)
 It triggers a new temperature measurement.
HTU21D_status_t HTU21D_ReadRawTemperature (Vector_raw_temperature_t *myRawTemperature)
 It reads the raw temperature.
HTU21D_status_t HTU21D_ReadTemperature (Vector_temperature_f *myTemperature)
 It reads the temperature.
HTU21D_status_t HTU21D_TriggerHumidity (void)
 It triggers a new humidity measurement.
HTU21D_status_t HTU21D_ReadRawHumidity (Vector_raw_humidity_t *myRawHumidity)
 It reads the raw humidity.
HTU21D_status_t HTU21D_ReadHumidity (Vector_humidity_f *myHumidity)
 It reads the humidity.
HTU21D_status_t HTU21D_BatteryStatus (HTU21D_user_register_status_t *myBattStatus)
 It gets the battery status.

Detailed Description

Example:

include "mbed.h" include "HTU21D.h"

HTU21D myTempRXSensor ( I2C_SDA, I2C_SCL, HTU21D::HTU21D_ADDRESS, 400000 ); Serial pc ( USBTX, USBRX ); // tx, rx

Ticker serial;

DigitalOut myled(LED1);

HTU21D::Vector_temperature_f myTemperature; HTU21D::Vector_humidity_f myHumidity;

void sendDATA ( void ) { HTU21D::HTU21D_user_register_status_t myBatteryStatus;

myled = 1;

Get Temperature myTempRXSensor.HTU21D_TriggerTemperature (); myTempRXSensor.HTU21D_ReadTemperature ( &myTemperature );

Get Humidity myTempRXSensor.HTU21D_TriggerHumidity (); myTempRXSensor.HTU21D_ReadHumidity ( &myHumidity );

Get Battery Status myTempRXSensor.HTU21D_BatteryStatus ( &myBatteryStatus );

Send data through the UART pc.printf( "\nTemperature: %0.01f\nHumidity: %0.01f\n", myTemperature.Temperature, myHumidity.Humidity );

if ( myBatteryStatus == HTU21D::STATUS_END_BATTERY_HIGH_2V25 ) pc.printf( "Battery status higher than 2.25V\r\n" ); else pc.printf( "Battery status lower than 2.25V\r\n" );

myled = 0; }

int main() { pc.baud ( 115200 );

myTempRXSensor.HTU21D_SoftReset (); myTempRXSensor.HTU21D_Init ( HTU21D::MODE_NO_HOLD_MASTER, HTU21D::RESOLUTION_12RH_14TEMP, HTU21D::HEATER_DISABLED );

serial.attach( &sendDATA, 1 ); // the address of the function to be attached ( sendDATA ) and the interval ( 1s )

Let the callbacks take care of everything while(1) sleep(); }

Library for the HTU21D Digital humidity sensor with temperature output.

Definition at line 89 of file HTU21D.h.

Member Enumeration Documentation

enum HTU21D_address_t

DEFAULT ADDRESSES.

Definition at line 95 of file HTU21D.h.

enum HTU21D_master_mode_t

MODE.

Enumerator:
MODE_HOLD_MASTER 

Mode Hold master

MODE_NO_HOLD_MASTER 

Mode No hold master

Definition at line 153 of file HTU21D.h.

enum HTU21D_status_t

INTERNAL CONSTANTS.

Enumerator:
I2C_SUCCESS 

I2C communication was fine

Definition at line 185 of file HTU21D.h.

enum HTU21D_user_register_heater_t

ON-CHIP HEATER.

Enumerator:
HEATER_ENABLED 

Heater enabled

HEATER_DISABLED 

Heater disabled

Definition at line 134 of file HTU21D.h.

enum HTU21D_user_register_otp_t

OTP RELOAD.

Enumerator:
OTP_ENABLED 

OTP enabled

OTP_DISABLED 

OTP disabled

Definition at line 142 of file HTU21D.h.

enum HTU21D_user_register_resolution_t

RESOLUTION.

Enumerator:
RESOLUTION_12RH_14TEMP 

Resolution: RH 12-bits, T 14-bits

RESOLUTION_8RH_12TEMP 

Resolution: RH 8-bits, T 12-bits

RESOLUTION_10RH_13TEMP 

Resolution: RH 10-bits, T 13-bits

RESOLUTION_11RH_11TEMP 

Resolution: RH 11-bits, T 11-bits

Definition at line 116 of file HTU21D.h.

enum HTU21D_user_register_status_t

STATUS: END OF BATTERY.

Enumerator:
STATUS_END_BATTERY_HIGH_2V25 

Status: RH 12-bits, T 14-bits

STATUS_END_BATTERY_LOW_2V25 

Status: RH 8-bits, T 12-bits

Definition at line 126 of file HTU21D.h.

Constructor & Destructor Documentation

HTU21D ( PinName  sda,
PinName  scl,
uint32_t  addr,
uint32_t  freq 
)

Create an HTU21D object connected to the specified I2C pins.

HTU21D.c.

Parameters:
sdaI2C data pin
sclI2C clock pin
addrI2C slave address
freqI2C frequency in Hz.

Digital humidity sensor with temperature output. Functions file.

Returns:
NA
Author:
Manuel Caballero
Date:
4/September/2017
Version:
4/September/2017 The ORIGIN
Precondition:
NaN.
Warning:
NaN
Precondition:
This code belongs to AqueronteBlog ( http://unbarquero.blogspot.com ).

Definition at line 20 of file HTU21D.cpp.

~HTU21D (  )

Delete HTU21D object.

Definition at line 28 of file HTU21D.cpp.

Member Function Documentation

HTU21D::HTU21D_status_t HTU21D_BatteryStatus ( HTU21D_user_register_status_t *  battStatus )

It gets the battery status.

HTU21D_BatteryStatus ( HTU21D_user_register_status_t* )

Read the user register to check the battery status.

Parameters:
[in]battStatus,:Variable to store the battery status.
[out]Statusof HTU21D_BatteryStatus.
Returns:
NA
Author:
Manuel Caballero
Date:
5/September/2017
Version:
5/September/2017 The ORIGIN
Precondition:
NaN
Warning:
NaN.

Definition at line 442 of file HTU21D.cpp.

HTU21D::HTU21D_status_t HTU21D_Init ( HTU21D_master_mode_t  myMode,
HTU21D_user_register_resolution_t  myResolution,
HTU21D_user_register_heater_t  myHeater 
)

It configures the device.

HTU21D_Init ( HTU21D_master_mode_t , HTU21D_user_register_resolution_t , HTU21D_user_register_otp_t )

It initializes the device.

Parameters:
[in]myMode,:Hold/No Hold master mode.
[in]myResolution,:Resolution of the sensor.
[in]myHeater,:Heater enabled or disabled.
[out]NaN.
Returns:
Status of HTU21D_Init.
Author:
Manuel Caballero
Date:
4/September/2017
Version:
4/September/2017 The ORIGIN
Precondition:
NaN
Warning:
NaN.

Definition at line 55 of file HTU21D.cpp.

HTU21D::HTU21D_status_t HTU21D_ReadHumidity ( Vector_humidity_f *  myhumidity )

It reads the humidity.

HTU21D_ReadHumidity ( Vector_humidity_f* )

Read a new humidity measurement.

Parameters:
[in]myhumidity,:Variable to store the humidity.
[out]Statusof HTU21D_ReadHumidity.
Returns:
NA
Author:
Manuel Caballero
Date:
5/September/2017
Version:
5/September/2017 The ORIGIN
Precondition:
NaN
Warning:
HTU21D_TriggerHumidity MUST be called before.

Definition at line 366 of file HTU21D.cpp.

HTU21D::HTU21D_status_t HTU21D_ReadRawHumidity ( Vector_raw_humidity_t *  myRawhumidity )

It reads the raw humidity.

HTU21D_ReadRawHumidity ( Vector_raw_humidity_t* )

Read a new raw humidity measurement.

Parameters:
[in]myRawhumidity,:Variable to store the raw humidity.
[out]Statusof HTU21D_ReadHumidity.
Returns:
NA
Author:
Manuel Caballero
Date:
5/September/2017
Version:
5/September/2017 The ORIGIN
Precondition:
NaN
Warning:
The measuring time depends on the chosen resolution.
HTU21D_TriggerHumidity MUST be called before.

Definition at line 408 of file HTU21D.cpp.

HTU21D::HTU21D_status_t HTU21D_ReadRawTemperature ( Vector_raw_temperature_t *  myRawtemperature )

It reads the raw temperature.

HTU21D_ReadRawTemperature ( Vector_raw_temperature_t* )

Read a new raw temperature measurement.

Parameters:
[in]myRawtemperature,:Variable to store the temperature.
[out]Statusof HTU21D_ReadTemperature.
Returns:
NA
Author:
Manuel Caballero
Date:
5/September/2017
Version:
5/September/2017 The ORIGIN
Precondition:
NaN
Warning:
HTU21D_TriggerTemperature MUST be called before.

Definition at line 270 of file HTU21D.cpp.

HTU21D::HTU21D_status_t HTU21D_ReadTemperature ( Vector_temperature_f *  mytemperature )

It reads the temperature.

HTU21D_ReadTemperature ( Vector_temperature_f* )

Read a new temperature measurement.

Parameters:
[in]mytemperature,:Variable to store the temperature.
[out]Statusof HTU21D_ReadTemperature.
Returns:
NA
Author:
Manuel Caballero
Date:
5/September/2017
Version:
5/September/2017 The ORIGIN
Precondition:
NaN
Warning:
HTU21D_TriggerTemperature MUST be called before.

Definition at line 229 of file HTU21D.cpp.

HTU21D::HTU21D_status_t HTU21D_SoftReset ( void   )

It resets the device by software.

HTU21D_SoftReset ( void )

Rebooting the HTU21D sensor switching the power off and on again.

Parameters:
[in]NaN.
[out]Statusof HTU21D_SoftReset.
Returns:
NA
Author:
Manuel Caballero
Date:
5/September/2017
Version:
5/September/2017 The ORIGIN
Precondition:
NaN
Warning:
The soft reset takes less than 15ms.

Definition at line 130 of file HTU21D.cpp.

HTU21D::HTU21D_status_t HTU21D_TriggerHumidity ( void   )

It triggers a new humidity measurement.

HTU21D_TriggerHumidity ( void )

Trigger a new humidity measurement.

Parameters:
[in]NaN.
[out]Statusof HTU21D_TriggerHumidity.
Returns:
NA
Author:
Manuel Caballero
Date:
5/September/2017
Version:
5/September/2017 The ORIGIN
Precondition:
NaN
Warning:
The measuring time depends on the chosen resolution.

Definition at line 302 of file HTU21D.cpp.

HTU21D::HTU21D_status_t HTU21D_TriggerTemperature ( void   )

It triggers a new temperature measurement.

HTU21D_TriggerTemperature ( void )

Trigger a new temperature measurement.

Parameters:
[in]NaN.
[out]Statusof HTU21D_TriggerTemperature.
Returns:
NA
Author:
Manuel Caballero
Date:
5/September/2017
Version:
5/September/2017 The ORIGIN
Precondition:
NaN
Warning:
The measuring time depends on the chosen resolution.

Definition at line 165 of file HTU21D.cpp.

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