SHT15

Table of Contents

    Note

    This page has been moved to the Components section of the website. Please see http://developer.mbed.org/components/SHT15-temperature-and-humidity/ .

    The SHT15 is a temperature and humidity sensor from Sensirion. The SHT15 digital humidity and temperature sensor is fully calibrated and offers high precision and excellent long-term stability at low cost. The digital CMOSens Technology integrates two sensors and readout circuitry on one single chip.

    SHT15 Datasheet

    HT15
    Sparkfun SHT15 Breakout board


    The Sparkfun SHT15 breakout board already includes the two I2C pullups (R1&R2 above) needed.

    Wiring

    mbedSHT15 sensor
    gndgnd
    Vout(3.3V)VCC
    P9(sda)Data
    p10(scl)SCK

    Here is a demo program using the SHTx library that prints out the temperature and humidity

    Import programSHT15_Example

    Example program for the SHT1x sensor driver



    /**
     * Copyright (c) 2010 Roy van Dam <roy@negative-black.org>
     * All rights reserved.
     *
     * Redistribution and use in source and binary forms, with or without
     * modification, are permitted provided that the following conditions
     * are met:
     * 1. Redistributions of source code must retain the above copyright
     *    notice, this list of conditions and the following disclaimer.
     * 2. Redistributions in binary form must reproduce the above copyright
     *    notice, this list of conditions and the following disclaimer in the
     *    documentation and/or other materials provided with the distribution.
     *
     * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
     * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
     * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     * SUCH DAMAGE.
     */
    
    #include "mbed.h"
    #include "SHTx/sht15.hpp"
    
    Serial pc(USBTX, USBRX);
    DigitalOut busy(LED1);
    
    // I used p9 and p10 here  but you
    // can use any other GPIO as well.
    SHTx::SHT15 sensor(p9, p10);
    
    int
    main() {
        // Speed things up a bit.
        sensor.setOTPReload(false);
        sensor.setResolution(true);
        
        while(1) {
            busy = true;
            sensor.update();
            busy = false;
            
            // Temperature in celcius
            sensor.setScale(false);
            pc.printf("Temperature [ %3.2f C ]\r\n", sensor.getTemperature());
            
            // Temperature in fahrenheit
            sensor.setScale(true);
            pc.printf("            [ %3.2f F ]\r\n", sensor.getTemperature());
            
            // Relative Humidity
            pc.printf("Humidity     [ %3.2f %% ]\r\n\n", sensor.getHumidity());
            
            wait(5);
        }
    }
    



    SHTtest

    Output from SHT15 Example Program