ESP-WROOM-32 compatibility with GravityTDS meter

Hi, I’m trying to use DFRobot TDS meter v1.0 for my project. However, the sensor comes default as not-calibrated which makes the result inaccurate. However, the library GravityTDS’ calibration example returns no result (0) which is impossible. How can I configure the example to work with ESP32?


The Calibration Example:

 DFRobot Gravity: Analog TDS Sensor/Meter
 This sample code shows how to read the tds value and calibrate it with the standard buffer solution.
 707ppm(1413us/cm)@25^c standard buffer solution is recommended.
 Created 2018-1-3
 By Jason <>
 GNU Lesser General Public License.
 See <> for details.
 All above must be included in any redistribution.
 /***********Notice and Trouble shooting***************
 1. This code is tested on Arduino Uno with Arduino IDE 1.0.5 r2 and 1.8.2.
 2. Calibration CMD:
     enter -> enter the calibration mode
     cal:tds value -> calibrate with the known tds value(25^c).
     exit -> save the parameters and exit the calibration mode

#include <EEPROM.h>
#include "GravityTDS.h"

#define TdsSensorPin A1
GravityTDS gravityTds;

float temperature = 25,tdsValue = 0;

void setup()
    gravityTds.setAref(5.0);  //reference voltage on ADC, default 5.0V on Arduino UNO
    gravityTds.setAdcRange(1024);  //1024 for 10bit ADC;4096 for 12bit ADC
    gravityTds.begin();  //initialization

void loop()
    //temperature = readTemperature();  //add your temperature sensor and read it
    gravityTds.setTemperature(temperature);  // set the temperature and execute temperature compensation
    gravityTds.update();  //sample and calculate 
    tdsValue = gravityTds.getTdsValue();  // then get the value