Trying to build a DHT11 block and keep getting this error in Simulink

Im trying to build this block but I get this error that I will provide below. I have followed exactly the steps from the matlab tutorials, so I have no idea what is the problem. Please if anyone knows I would appreciate the help.

C:/Users/user/DOCUME~1/MATLAB/R2024b/ArduinoStaticLibrary/ArduinoUno/FasterRuns/MW_RebuildSrc_Core.o -lm -lcomm -lcore DHT11_DDAppGeneratedModel.o: In function `DHT11_DDAppGeneratedModel_step': DHT11_DDAppGeneratedModel.c:(.text.DHT11_DDAppGeneratedModel_step+0xc0): undefined reference to `stepFunctionDHT11' DHT11_DDAppGeneratedModel.o: In function `DHT11_DDAppGeneratedModel_initialize': DHT11_DDAppGeneratedModel.c:(.text.DHT11_DDAppGeneratedModel_initialize+0x5c): undefined reference to `setupFunctionDHT11' collect2.exe: error: ld returned 1 exit status gmake[1]: *** [../DHT11_DDAppGeneratedModel.elf] Error 1 gmake[1]: Leaving directory `C:/Users/user/Desktop/DHT11/DHT11_DDAppGeneratedModel_ert_rtw' gmake: *** [all] Error 2 C:\Users\user\Desktop\DHT11\DHT11_DDAppGeneratedModel_ert_rtw>echo The make command returned an error of 2 The make command returned an error of 2 C:\Users\user\Desktop\DHT11\DHT11_DDAppGeneratedModel_ert_rtw>exit /B 1 ### Build procedure for DHT11_DDAppGeneratedModel aborted due to an error.

Build Summary

Top model targets: Model Build Reason Status Build Duration ===================================================================================================================================================== DHT11_DDAppGeneratedModel Information cache folder or artifacts were missing. Failed to build. For more information, see build log. 0d 0 of 1 models built (0 models already up to date) Build duration: 0h 0m 29.469s

Error(s) encountered while building "DHT11_DDAppGeneratedModel"

Component:Simulink | Category:Block diagram error

And my code is as follows:

#include "C:\Users\user\Desktop\DHT11\DHT11.h"

#include "Adafruit_Sensor.h"

#include "DHT.h"

#include "DHT_U.h"

#include "Arduino.h"

#define DHTPIN 10

#define DHTTYPE DHT11

DHT_Unified dht(DHTPIN, DHTTYPE);

uint32_t delayMS;

void setupFunctiondht11Sensor(uint32_T * dataDelay,int size_vector__1){

Serial.begin(9600);

dht.begin();

delayMS = dataDelay;

}

void stepFunctiondht11Sensor(float * Humidity,int size_vector_1,float * Temperature,int size_vector_2){

delay(delayMS);

sensors_event_t event;

dht.temperature().getEvent(&event);

if (isnan(event.temperature)) {

}

else {

*Temperature=event.temperature;

}

dht.humidity().getEvent(&event);

if (isnan(event.relative_humidity)) {

}

else {

*Humidity=event.relative_humidity;

}

}

Answer 1

[Divyanshu]

Hello @ATHANASIOS,

I think you are following the example documentation Create DHT11 Sensor Block.

A possible reason for getting error 'undefined reference to stepfunctionDHT11' during the build can be missing pre-requisite drivers, files or packages.

As mentioned in the above example documentation link, the prerequisites for the example are:

• Download the DHT-sensor-library drivers for the sensor from the GitHub.
• Download the dependent files Adafruit Unified Sensor from the GitHub.
• Ensure to install the Simulink support package for arduino hardware.

Hope this helps!

[ATHANASIOS]

Thank you for the answer,

Its true I follow that example, however I have downloaded all the libraries needed and the support package.

Answer 2

[Mohamadmahdi]

I followed all of the above steps, but the error has not been resolved.