Where can I find the Rpm counter value?

[FDY-fr]

I am developing a monitoring system for my 2GM20 Yanmar motor (temperature X4, total run time, trip time, RPM,…). This is based on an ESP32 board dev kit C.
Everything works well and I can get all the motor sensors values displayed with Openplotter (RPI 5). I used all the examples to create my own source code. I want to add an e-ink display to the ESP32 that monitors the motor to display the motor parameter “locally”. I have an issue as I am not able to get locally the RPM (or frequency) value that is sent to signalk. Would you know how I could get that value locally so that I can display that value on my local e-ink display?

Thanks in advance for your support. If you need additional info, do not hesitate to ask.

[FDY-fr]

Hello experienced software developer.
could someone help me to fix my issue with the RPM counter as describe in my message above?
thanksssss for your support
Francis

[FDY-fr]

Hello @caballero03
I tried your proposed modifications and it compiled well but when I added the line "->connect_to(displayMotorRPM_)" to my code below I got the following error. I tried things to fix it but I did not succeed.
Your help will be greatly appreciated one more time.
Thanks again
Francis

[FDY-fr]

hello again @caballero03

I did more research on internet and found the an example that I tried in my code which is working as I am able to display the RPM on the e-paper screen.

If I keep the "->connect_to(new SKOutputFloat("propulsion.engine.revolutions", config_path_skpath));" after the lines I added, the compilation fails. So I had to create two separated codes: one for the e-paper and one for the signalK. I would have prefered to have just one code for both but I cannot make it working.
As I am a beginner in C++ and SensESP I cannot fix it....
Any thoughts?
Francis

[kinyo666]

You just have to chain the objects with connect_to() and declare a callback for your LambdaConsumer :

// callback out of setup()
void getRPMValue(float value) {
    float localRPMvalue = value;
};

// setup()
MovingAverage *mov_avg = new MovingAverage(2, 1.0, "/EngineRPM/MovingAVG");
mov_avg->connect_to(new LambdaConsumer<float>(getRPMValue));

sensorRPM->connect_to(new Frequency(multiplier, config_path_calibrate))
                  ->connect_to(mov_avg)
                  ->connect_to(new SKOutputFloat("propulsion.engine.revolutions", config_path_skpath));

PS : You should avoid using config path name with space in as it is stored as-is in the filesystem and it is not hashed.

[FDY-fr]

Thanks @caballero03 and @kinyo666 for your support. It is now working nicely as I am able to get the rpm value on both the SK server and my e-paper local display.
i will therefore close that issue and marked it as solved.
thanks again.

[kinyo666]

It could be interesting to share your code / setup as I am doing the same project on a Volvo Penta engine.

Here is my discord username : kinyo666_85300
(en français)

[FDY-fr]

@caballero03 , @kinyo666
Ok no problem.
i will clean up a little all the code I wrote and I will upload it on GitHub for you to access it.
enjoy your Easter weekend.

[FDY-fr]

@caballero03, @kinyo666
hi guys,
I have uploaded the latest code at: https://github.com/FDY-fr/MotorMonitoring
I also added the schematics
thanks again for your support
francis

[kinyo666]

I quickly reviewed your code. In your lib_deps in platformio.ini you should remove the http link (which doesn't match to any lib) and replace it by SignalK/SensESP@^3.1.0 for the lastest stable version. It needs some adaptation from a SensESP <= 3.0.0 code.

If you need to use configuration path, you must add a ConfigItem object like this :

      Frequency *freq = new Frequency(multiplier, config_path_calibrate);
      // [...]
      ConfigItem(freq)
      ->set_title("Frequency - Multiplier")
      ->set_description("Alternator W ratio")
      ->set_sort_order(0);

You can then connect to the ESP32 and dynamically modify without recompiling your code.

For the PC817 IR sensor, are you still using the analog gauge in the dashboard ?
I am looking for a solution to keep the old one and add a digital dashboard without disturbing the W signal.