DFRobot_ESP_PH_WITH_ADC_BY_GREENPONIK Library

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ESP Ph Reading and Calibration @ https://github.com/greenponik/DFRobot_ESP_PH_WITH_ADC_BY_GREENPONIK

using Gravity: Analog pH Sensor / Meter Kit V2, SKU:SEN0161-V2 + ADC ADS1115

based on DFRobot_PH @ https://github.com/DFRobot/DFRobot_PH

IMPORTANT : to make it work, you will need the help of an additionnal ADC converter because the one on the ESP32 isn't accurate enough. Here we used an ADS1115 from Adafruit You can find it here : https://www.adafruit.com/product/1085

And here is the library you'll need to add to your sketch : https://github.com/adafruit/Adafruit_ADS1X15

Example

#include <Arduino.h>
#include "DFRobot_ESP_PH_WITH_ADC.h"
#include "OneWire.h"
#include "DallasTemperature.h"
#include "Adafruit_ADS1015.h"
#include "EEPROM.h"

#define ONE_WIRE_BUS 15
OneWire oneWire(ONE_WIRE_BUS);
DallasTemperature sensors(&oneWire);

DFRobot_ESP_PH_WITH_ADC ph;
Adafruit_ADS1115 ads;

float voltage, phValue, temperature = 25;

float readTemperature()
{
	//add your code here to get the temperature from your temperature sensor
	sensors.requestTemperatures();
	return sensors.getTempCByIndex(0);
}

void setup()
{
	Serial.begin(115200);
	EEPROM.begin(32);//needed EEPROM.begin to store calibration k in eeprom
	ph.begin();
	sensors.begin();
	ads.setGain(GAIN_ONE);
	ads.begin();
}

void loop()
{
	static unsigned long timepoint = millis();
	if (millis() - timepoint > 1000U) //time interval: 1s
	{
		timepoint = millis();
		/**
		 * index 0 for adc's pin A0
 		 * index 1 for adc's pin A1
		 * index 2 for adc's pin A2
		 * index 3 for adc's pin A3
		*/
		voltage = ads.readADC_SingleEnded(1) / 10; // read the voltage
		Serial.print("voltage:");
		Serial.println(voltage, 4);

		temperature = readTemperature(); // read your temperature sensor to execute temperature compensation
		Serial.print("temperature:");
		Serial.print(temperature, 1);
		Serial.println("^C");

		phValue = ph.readPH(voltage, temperature); // convert voltage to pH with temperature compensation
		Serial.print("pH:");
		Serial.println(phValue, 4);
	}
	ph.calibration(voltage, temperature); // calibration process by Serail CMD
}

Compatibility

MCU	Work Well	Work Wrong	Untested	Remarks
ESP32	√
ESP8266		√

Credits

Written by Mickael Lehoux from @greenponik

Based on written by Jiawei Zhang(Welcome to our website)

Tutorial here

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