Circuit Documentation

Summary

This circuit is designed to interface an ESP32 Devkit V1 microcontroller with an HC-SR04 Ultrasonic Sensor, a TDS Sensor Module, and a pH Degree Sensor Module for the purpose of measuring water level, total dissolved solids (TDS), and pH level. The circuit is powered by a 5V battery. The ESP32 reads the sensors' outputs and processes the data, which is then available for monitoring or further processing.

Component List

ESP32 Devkit V1

• Description: A microcontroller development board based on the ESP32 chip, featuring Wi-Fi and Bluetooth connectivity.
• Pins: 3V3, GND, D15, D2, D4, RX2, TX2, D5, D18, D19, D21, RX0, TX0, D22, D23, EN, VP, VN, D34, D35, D32, D33, D25, D26, D27, D14, D12, D13, VIN

HC-SR04 Ultrasonic Sensor

• Description: An ultrasonic distance sensor capable of measuring distances by emitting ultrasonic waves and timing their reflection.
• Pins: VCC, TRIG, ECHO, GND

TDS Sensor Module

• Description: A sensor module used to measure the total dissolved solids in water, indicating water quality.
• Pins: TDS Negative, TDS Positive, TDS A

pH Degree Sensor Module

• Description: A sensor module used to measure the pH level of a solution, indicating its acidity or alkalinity.
• Pins: pH Negative, pH Positive, pH A

5V Battery

• Description: A power source providing a stable 5V supply to the circuit.
• Pins: Positive, Negative

Wiring Details

ESP32 Devkit V1

• D22 connected to HC-SR04 Ultrasonic Sensor ECHO
• D23 connected to HC-SR04 Ultrasonic Sensor TRIG
• D34 connected to TDS Sensor Module TDS A
• D35 connected to pH Degree Sensor Module pH A

HC-SR04 Ultrasonic Sensor

• VCC connected to 5V Battery Positive
• TRIG connected to ESP32 Devkit V1 D23
• ECHO connected to ESP32 Devkit V1 D22
• GND connected to 5V Battery Negative

TDS Sensor Module

• TDS Positive connected to 5V Battery Positive
• TDS Negative connected to 5V Battery Negative
• TDS A connected to ESP32 Devkit V1 D34

pH Degree Sensor Module

• pH Positive connected to 5V Battery Positive
• pH Negative connected to 5V Battery Negative
• pH A connected to ESP32 Devkit V1 D35

5V Battery

• Positive connected to HC-SR04 Ultrasonic Sensor VCC, TDS Sensor Module TDS Positive, pH Degree Sensor Module pH Positive
• Negative connected to HC-SR04 Ultrasonic Sensor GND, TDS Sensor Module TDS Negative, pH Degree Sensor Module pH Negative

Documented Code

// Include necessary libraries
#include <Arduino.h>

// Define pins
#define TRIG_PIN 23 // Trigger pin for HC-SR04
#define ECHO_PIN 22 // Echo pin for HC-SR04
#define TDS_PIN 34  // Analog pin for TDS sensor
#define PH_PIN 35   // Analog pin for pH sensor

void setup() {
    Serial.begin(115200); // Start serial communication
    pinMode(TRIG_PIN, OUTPUT); // Set trigger pin as output
    pinMode(ECHO_PIN, INPUT);  // Set echo pin as input
}

void loop() {
    // Read water level using ultrasonic sensor
    long duration, distance;
    
    // Clear the trigger
    digitalWrite(TRIG_PIN, LOW);
    delayMicroseconds(2);
    
    // Set trigger high for 10 microseconds
    digitalWrite(TRIG_PIN, HIGH);
    delayMicroseconds(10);
    digitalWrite(TRIG_PIN, LOW);
    
    // Read the echo pin
    duration = pulseIn(ECHO_PIN, HIGH);
    
    // Calculate distance in cm (speed of sound = 340 m/s)
    distance = (duration * 0.034) / 2; // Divide by 2 because the sound travels to the object and back
    
    // Read TDS and pH values
    int tdsValue = analogRead(TDS_PIN); // Read TDS value
    int phValue = analogRead(PH_PIN);   // Read pH value

    // Print values to Serial Monitor
    Serial.print("Water Level (cm): ");
    Serial.println(distance);
    Serial.print("TDS Value: ");
    Serial.println(tdsValue);
    Serial.print("pH Value: ");
    Serial.println(phValue);
    
    // Wait for a second before the next reading
    delay(1000);
}

This code is designed to be uploaded to the ESP32 Devkit V1. It initializes the pins connected to the sensors, reads the distance from the HC-SR04 Ultrasonic Sensor, and the TDS and pH values from their respective sensors. The results are printed to the Serial Monitor every second.