Temperature?

[chriscummings]

Nathanne,

I'm trying to understand converting the TO pin voltage to a human readable celsius or fahrenheit. I see in your example you are calling ph4502c.read_temp(). However, when I look at that function, it seems like it just returns the straight pin value, not any sort of conversion.

int PH4502C_Sensor::read_temp() {
    return analogRead(this->_temp_pin);
}

For example, I'll just get a value of 752.00. I can't find any datasheet explaining what the equation should be for temperature.

Thank you.

[nthnn]

Hi Chris!

Even I can't seem to find any useful information about the sensor's temperature pin from the manufacturer or from the internet. Exact reason why I wrote read_temp() function the way it is.

However, the best way I can recommend to convert it to a meaningful temperature value is to calibrate it on the go. For instance,

int sensorValue = analogRead(sensorPin);
float temperature = map(sensorValue, 0, 1023, minTemperature, maxTemperature);

Just replace the minTemperature with the lowest temperature possible that you can get from your sensor, same with the maxTemperature for highest temperature you can get.

[chriscummings]

Nathanne,

Thank you for your response! 👍

I'll see if I can find the high/low temp info on the thermistor before I try to thermally test it myself.

[chriscummings]

Closing. Thanks again!