Adding sensors on raspberry


#1

Dear All,

My name is Vuk and I am pretty new in this stuff. recently I needed a device to measure temperature and himidity in my rack installations and I’ve heard about thinger. I have a lot of raspberry pi devices and I would like to add a DHT temperature and humidity sensor on them. It went all good until adding resources showed up where I am stuck. Before You start criticizing me, I have searched a LOT and I didn’t find any tutorial which I can use. They are mostly for arduino. Is there any easy way to add a sensor in main.cpp and add a fan trigger (later if I ever make sensor ;(
).
Please help…

Best regards.


#2

I have this in the main.cpp

int main(int argc, char *argv[])
{
thinger_device thing(USER_ID, DEVICE_ID, DEVICE_CREDENTIAL);

// define thing resources here. i.e, this is a sum example
    // define the resource just once in the setup
    thing["TempHum"] >> [](pson &out){
            out["temperature"] = dht.readTemperature();
            out["humidity"] = dht.readHumidity();
    };
thing.start();
return 0;

}

and I get this when I try to execute ./install.sh

root@thinger:/home/pi/Linux-Client/install/raspberry# ./install.sh
– OpenSSL Version: 1.1.1c
– Configuring done
– Generating done
– Build files have been written to: /home/pi/Linux-Client/install/raspberry/build
[ 50%] Building CXX object CMakeFiles/thinger.dir/src/main.cpp.o
/home/pi/Linux-Client/src/main.cpp: In lambda function:
/home/pi/Linux-Client/src/main.cpp:38:24: error: ‘dht’ was not declared in this scope
out[“temperature”] = dht.readTemperature();
^~~
/home/pi/Linux-Client/src/main.cpp:38:24: note: suggested alternative: ‘dh_st’
out[“temperature”] = dht.readTemperature();
^~~
dh_st
make[3]: *** [CMakeFiles/thinger.dir/build.make:63: CMakeFiles/thinger.dir/src/main.cpp.o] Error 1
make[2]: *** [CMakeFiles/Makefile2:73: CMakeFiles/thinger.dir/all] Error 2
make[1]: *** [CMakeFiles/Makefile2:85: CMakeFiles/thinger.dir/rule] Error 2
make: *** [Makefile:164: thinger] Error 2
[ 50%] Building CXX object CMakeFiles/thinger.dir/src/main.cpp.o
/home/pi/Linux-Client/src/main.cpp: In lambda function:
/home/pi/Linux-Client/src/main.cpp:38:24: error: ‘dht’ was not declared in this scope
out[“temperature”] = dht.readTemperature();
^~~
/home/pi/Linux-Client/src/main.cpp:38:24: note: suggested alternative: ‘dh_st’
out[“temperature”] = dht.readTemperature();
^~~
dh_st
make[2]: *** [CMakeFiles/thinger.dir/build.make:63: CMakeFiles/thinger.dir/src/main.cpp.o] Error 1
make[1]: *** [CMakeFiles/Makefile2:73: CMakeFiles/thinger.dir/all] Error 2
make: *** [Makefile:130: all] Error 2

My raspbian is Raspbian Buster Lite.

Someone knows whats wrong?


#3

this is your problem, where is dht declared? is this the whole code?


#4

Hello, thanks for reply. yes, that’s the whole code. I have no idea how to declare dht… ;(