Circuit Documentation

Summary

This document provides a detailed overview of a circuit designed to monitor soil moisture levels and control a water pump based on the moisture readings. The circuit includes an ESP32 microcontroller, an I2C LCD screen for display, a soil moisture sensor and module, a 5V relay, and a 5V mini water pump. The circuit is powered by a 3xAAA battery pack with a switch.

Component List

1. I2C LCD 16x2 Screen

   • Description: A 16x2 character LCD screen with I2C interface.
   • Pins: SCL, SDA, VCC (5V), GND, VDD, VO, RS, RW, E, D0, D1, D2, D3, D4, D5, D6, D7, BLA, BLK

2. Soil Moisture Module

   • Description: A module to interface with the soil moisture sensor.
   • Pins: positive, negative, Analog, Digital, Ground, VCC

3. ESP32 (30 pin)

   • Description: A powerful microcontroller with Wi-Fi and Bluetooth capabilities.
   • Pins: EN, VP, VN, D34, D35, D32, D33, D25, D26, D27, D14, D12, D13, GND, Vin, D23, D22, TX0, RX0, D21, D19, D18, D5, TX2, RX2, D4, D2, D15, 3V3

4. Soil Moisture Sensor

   • Description: A sensor to measure the moisture level in the soil.
   • Pins: VCC, GND, SIG

5. 5V Relay

   • Description: A relay module to control high-power devices.
   • Pins: Normally Open, Common terminal, Normally Closed, In, GND, VCC

6. 5V Mini Water Pump

   • Description: A small water pump powered by 5V.
   • Pins: positive pin, negative pin

7. 3xAAA Battery with Switch (bare wire)

   • Description: A battery pack with a switch to power the circuit.
   • Pins: POS, NEG

Wiring Details

I2C LCD 16x2 Screen

• SCL connected to ESP32 D22
• SDA connected to ESP32 D21
• VCC (5V) connected to 5V Relay VCC, Soil Moisture Module VCC, ESP32 Vin
• GND connected to 5V Relay GND, Soil Moisture Module Ground, ESP32 GND

Soil Moisture Module

• positive connected to Soil Moisture Sensor VCC
• negative connected to Soil Moisture Sensor GND
• Analog connected to ESP32 D33
• Ground connected to 5V Relay GND, I2C LCD 16x2 Screen GND, ESP32 GND
• VCC connected to 5V Relay VCC, I2C LCD 16x2 Screen VCC (5V), ESP32 Vin

ESP32 (30 pin)

• D22 connected to I2C LCD 16x2 Screen SCL
• D21 connected to I2C LCD 16x2 Screen SDA
• Vin connected to 5V Relay VCC, I2C LCD 16x2 Screen VCC (5V), Soil Moisture Module VCC
• GND connected to 5V Relay GND, I2C LCD 16x2 Screen GND, Soil Moisture Module Ground
• D33 connected to Soil Moisture Module Analog
• D4 connected to 5V Relay In

Soil Moisture Sensor

• VCC connected to Soil Moisture Module positive
• GND connected to Soil Moisture Module negative

5V Relay

• VCC connected to I2C LCD 16x2 Screen VCC (5V), Soil Moisture Module VCC, ESP32 Vin
• GND connected to I2C LCD 16x2 Screen GND, Soil Moisture Module Ground, ESP32 GND
• In connected to ESP32 D4
• Normally Open connected to 5V Mini Water Pump positive pin
• Common terminal connected to 3xAAA Battery with Switch POS

5V Mini Water Pump

• positive pin connected to 5V Relay Normally Open
• negative pin connected to 3xAAA Battery with Switch NEG

3xAAA Battery with Switch (bare wire)

• POS connected to 5V Relay Common terminal
• NEG connected to 5V Mini Water Pump negative pin

Code

No code is provided for this circuit.