This is a library to read out sensor values from Silicon Labs' si70xx-range of relative humidity and temperature sensors.

Dependents:   MemLCD-Temperature-Humidity-Demo lab123


All examples in this repo are considered EXPERIMENTAL QUALITY, meaning this code has been created as one-off proof-of-concept and is suitable as a demonstration for experimental purposes only. This code will not be regularly maintained by Silicon Labs and there is no guarantee that these projects will work across all environments, SDK versions and hardware.


This library targets mbed's asynchronous transfer APIs, so it can only be used in conjunction with platforms supporting these APIs.

The library is currently compatible with Si7013, Si7020 and Si7021 parts.


Include mbed low-power to use this driver

#include "mbed.h"
#include "SILABS_RHT.h"
I2C sensorI2C(PD6, PD7); //PD6=SDA, PD7=SCL
silabs::SILABS_RHT rhtSensor(&sensorI2C);
volatile bool busChecked = false;
void respondedCallback( void ) {
    busChecked = true;

int main() {
    rhtSensor.check_availability(si7021, respondedCallback);
    while(busChecked == false) sleep();
    busChecked = false;
    rhtSensor.measure(si7021, respondedCallback);
    while(busChecked == false) sleep();

    if(rhtSensor.get_active()) {
        printf("Temperature: %d.%03d degC\n", rhtSensor.get_Temperature()/1000, rhtSensor.get_Temperature()%1000);
    } else {
        printf("No sensor found\n");

    while(1) sleep();


Download repository: zip gz

Files at revision 2:83a8b7df827f

Name Size Actions
SILABS_RHT.cpp 7835 Revisions Annotate
SILABS_RHT.h 4313 Revisions Annotate