David Maitland

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8 years, 7 months ago.

Struggling to get updates from this library

So I'm trying to get this library working on my Happy Gecko dev board (first ever cortex development). I used the MemLCD-Temperature-Humidity-Demo as an example. I get the first temperature reading over serial, but each reading after is exactly the same value. Only after you hit reset on the board you get a real up to date reading from the sensor.

I'm calling the rhtSensor.measure method and waiting for the callback until I call rhtSensor.get_temperature() but it's never different. Am I doing something stupid here?

#include "SILABS_RHT.h"

DigitalOut status(LED1); // Status LED 1

Serial serial(USBTX, USBRX); // Setup USB serial

// Setup sensor

I2C sensorI2C(PD6, PD7);
DigitalOut SENS_EN(PC8);
silabs::SILABS_RHT rhtSensor(&sensorI2C);

// Variables

volatile bool busChecked = false;

// Functions
 
void respondedCallback(void) {
    busChecked = true;
}

int getTemp(void) {

    status = 1; // Turn on status LED
    
    busChecked = false;
    
    rhtSensor.measure(si7021, respondedCallback);

    while(busChecked == false) sleep();

    while(rhtSensor.get_temperature() == 0);
    
    status = 0; // Turn on status LED
        
    return rhtSensor.get_temperature();
    // return rhtSensor.get_humidity()
    
}

int main() {

    SENS_EN = 1; // Enable sensor
    
    wait(1);
    
    rhtSensor.check_availability(si7021, respondedCallback);
    
    while(busChecked == false) sleep();
    
    while(1) {
        
        serial.printf("%02d.%01d\n", getTemp() / 1000);
        
        wait(3);

    }

}

Question relating to:

Last updated: 05 May 2015
This is a library to read out sensor values from Silicon Labs' si70xx-range of relative humidity and temperature sensors. I2C, RHT, sensor, Si7013, Si7020, Si7021, Silicon Labs, silicon_labs, siliconlabs
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