SHT21

class SHT21

Driver for SHT21 I2C temperature and humidity sensor. More...

Public Functions

Type	Name
	SHT21 (I2C * i2c)
float	readTemp ()
float	readHumidity ()
int	reset ()
int	setPrecision (char precision)

Detailed Description

SHT21 Connection class, utilizing a I2C interface Example:

#include "mbed.h"
#include "SHT21_ncleee.h"


DigitalOut myled(LED1);
Serial pc(USBTX, USBRX);
I2C i2c(p28,p27);
SHT21 sht(&i2c);

int main() 
{

    pc.printf("Hello World...\n\tTesting temperature Sensor\n");

    int temperature = sht.readTemp();

    pc.printf("Temperature is: %d \n", temperature);

    pc.printf("Experiment complete...\n");

}

Public Functions Documentation

function SHT21

SHT21::SHT21 (
    I2C * i2c
)

Constructor - create a connection to a SHT21 temperature and humidity sensor through an I2C interface

Parameters:

• *i2c a pointer to the i2c interface that is used for communication

• frequency - I2C frequency

function readTemp

float SHT21::readTemp ()

Read the temperature value from the sensor Involves triggering the measuring unit then waiting for 100ms for the measuring to complete before reading the temperature

Parameters:

• returns a value representing the temperature in degrees centigrade

function readHumidity

float SHT21::readHumidity ()

Read the humidity value from the sensor Involves triggering the measuring unit then waiting for 100ms for the measuring to complete before reading the humidity

Parameters:

• returns the percentage humidity

function reset

int SHT21::reset ()

Perform a soft-reset of the sensor unit.

function setPrecision

int SHT21::setPrecision (
    char precision
)

Set the precision of the measuring //Data precision settings //RH 12 T 14 - default

define SHT_PREC_1214 0x00

//RH 8 T 10

define SHT_PREC_0812 0x01

//RH 10 T 13

define SHT_PREC_1013 0x80

//RH 11 T 11

define SHT_PREC_1111 0x81

Parameters:

• precision - the precision, refer to above or datasheet.

The documentation for this class was generated from the following file: D:/w/hw-libs/\_libs\_/libraries/SHT21\_ncleee.h