Custom sensor 'no matching function for call' error

ESPHome
1

Hi. I am new in c++, and I try to create custom sensor for my boiler. I’m using OpenTherm Arduino/ESP8266 Library

My .h file:

#include "esphome.h"
#include "OpenTherm.h"

class OpenThermSensor : public PollingComponent, public Sensor
{
public:
    const int inPin = 4;
    const int outPin = 5;

    OpenTherm ot = OpenTherm(inPin, outPin);

    OpenThermSensor() : PollingComponent(1000) {}

    void setup() override
    {
        ot.begin(handleInterrupt);
    }

    void update() override
    {
        publish_state(ot.getBoilerTemperature());
    }

    void handleInterrupt()
    {
        ot.handleInterrupt();
    }
};

But on compile error:

In file included from src/main.cpp:12:0:
src/esp_opentherm.h: In member function 'virtual void OpenThermSensor::setup()':
src/esp_opentherm.h:16:33: error: no matching function for call to 'OpenTherm::begin(<unresolved overloaded function type>)'
         ot.begin(handleInterrupt);
                                 ^
src/esp_opentherm.h:16:33: note: candidates are:
In file included from src/esp_opentherm.h:2:0,
                 from src/main.cpp:12:
/data/heater/.piolibdeps/heater/OpenTherm Library/src/OpenTherm.h:118:7: note: void OpenTherm::begin(void (*)())
  void begin(void(*handleInterruptCallback)(void));
       ^
/data/heater/.piolibdeps/heater/OpenTherm Library/src/OpenTherm.h:118:7: note:   no known conversion for argument 1 from '<unresolved overloaded function type>' to 'void (*)()'
/data/heater/.piolibdeps/heater/OpenTherm Library/src/OpenTherm.h:119:7: note: void OpenTherm::begin(void (*)(), void (*)(long unsigned int, OpenThermResponseStatus))
  void begin(void(*handleInterruptCallback)(void), void(*processResponseCallback)(unsigned long, OpenThermResponseStatus));
       ^
/data/heater/.piolibdeps/heater/OpenTherm Library/src/OpenTherm.h:119:7: note:   candidate expects 2 arguments, 1 provided
*** [/data/heater/.pioenvs/heater/src/main.cpp.o] Error 1

Why? I can’t understand…

upd: in arduaino scetch it builds, why not builds in ESPHome?

2

Out of my depth here. But maybe order. Try to put the handleInterrupt() function higher up above the setup function.

The arduino i think is very generous about the declaration order. handleInterrupt() is not part of any h file. So maybe order comes to play here.
Maybe worth a try at least.

/Mattias

3

I tried to do this, it doesn’t help…

4

I think that the problem is another.

The handleInterrupt() is a member function. That means that it’s probably not a the correct function pointer that you are looking for. Because the openTerm requires a c function pointer.
When you declare the function in arduino. Then i becomes a c function which works.
I do not have any solution for you. Maybe this is what is your problem.


I hope you find a solution. Sorry I could not help you more.
/Mattias
5

This code compiles:

class OpenThermSensor : public PollingComponent, public Sensor
{
public:
    OpenTherm ot = OpenTherm(inPin, outPin);

    OpenThermSensor() : PollingComponent(1000) {}

    void setup() override
    {
        ot.begin(&OpenThermSensor::handleInterrupt);
    }

    void update() override
    {
        publish_state(ot.getBoilerTemperature());
    }

    static void handleInterrupt()
    {
    
    }
};

But I can’t access ‘ot’ in static function… Is there any way to make ‘ot’ static?

6

I found this. He has solved it.

Check the opentherm_component.h.

He declare the handleInterrupt() outside the class.
and make an ot instance that he call from handleInterrupt()

// Configuración OpenTherm
const int inPin = D5; 
const int outPin = D6; 

OpenTherm ot(inPin, outPin, false);

ICACHE_RAM_ATTR void handleInterrupt() {
	ot.handleInterrupt();
}


class OpenthermComponent: public PollingComponent {
private:
  const char *TAG = "opentherm_component";
...

/Mattias

7

Yes, it works !!! :slight_smile:

8

Awesome.
/Mattias