const int analogPin = A0;  // Analog pin connected to the output of the TDS sensor
const float voltageReference = 5.0;  // Arduino Uno voltage reference
const float tdsFactor = 0.5;  // TDS conversion factor

void setup() {
  Serial.begin(9600);
}

void loop() {
  // Read analog value from the TDS sensor
  int rawValue = analogRead(analogPin);
  
  // Convert raw analog value to voltage
  float voltage = (float)rawValue * voltageReference / 1023.0;
  
  // Convert voltage to TDS value using conversion factor
  float tdsValue = voltage * tdsFactor;

  // Print TDS value to Serial Monitor
  Serial.print("TDS (ppm): ");
  Serial.println(tdsValue);
  
  delay(1000);  // Adjust delay as needed
}
/*In this code:

We define analogPin as the analog pin connected to the output of the TDS sensor.
voltageReference is set to 5.0V, which is the reference voltage of the Arduino Uno.
tdsFactor is a conversion factor to convert the analog voltage to TDS value. This factor depends on the specifications of your TDS sensor module.
In the setup() function, we initialize serial communication.
In the loop() function, we read the raw analog value from the TDS sensor using analogRead().
We convert the raw analog value to voltage by scaling it based on the reference voltage (5.0V) and the ADC resolution (1023 steps).
We multiply the voltage by the TDS conversion factor to get the TDS value in parts per million (ppm).
We print the TDS value to the Serial Monitor.
Adjust the delay as needed to control the sampling frequency.
Please note that TDS sensors require proper calibration to accurately measure TDS levels. Calibration typically involves comparing the sensor readings with standard TDS solutions of known concentrations. The conversion factor (tdsFactor) may need to be adjusted based on your calibration results and the characteristics of your specific TDS sensor module.*/