Circuit Documentation

Summary

The circuit in question is designed to interface an Arduino UNO with a variety of sensors and an I2C LCD display. The sensors include a heart pulse sensor and two soil moisture sensors, one of which is a SparkFun Soil Moisture Sensor and the other is a generic soil moisture module. The circuit is powered by a 9V battery, which supplies power to the Arduino UNO as well as the sensors and the LCD display through various connections. The Arduino UNO reads the analog signals from the heart pulse sensor and the soil moisture module and communicates with the I2C LCD to display relevant information.

Component List

Arduino UNO

• Microcontroller board based on the ATmega328P
• It has 14 digital input/output pins, 6 analog inputs, a 16 MHz quartz crystal, a USB connection, a power jack, an ICSP header, and a reset button.

Heart Pulse Sensor

• A plug-and-play heart-rate sensor for Arduino
• It can be used to measure the electrical activity of the heart.

SparkFun Soil Moisture Sensor

• A simple breakout for measuring the moisture in soil and similar materials
• The two large exposed pads function as probes for the sensor, together acting as a variable resistor.

Soil Moisture Module

• A soil moisture detection module that can be used to detect moisture levels of the soil.
• It provides both analog and digital outputs.

16x2 I2C LCD

• A 16 character by 2 line display that is compatible with the I2C protocol
• It reduces the number of GPIOs used on the Arduino.

9V Battery

• A standard 9V battery used to provide power to the circuit.

Wiring Details

Arduino UNO

• 5V connected to VCC of Heart Pulse Sensor, Soil Moisture Module, and 16x2 I2C LCD
• GND connected to GND of 16x2 I2C LCD and Heart Pulse Sensor, and "-" of 9V battery
• Vin connected to "+" of 9V battery
• A0 connected to SIGNAL of Heart Pulse Sensor
• A1 connected to Analog of Soil Moisture Module
• A4 (SDA) connected to SDA of 16x2 I2C LCD
• A5 (SCL) connected to SCL of 16x2 I2C LCD

Heart Pulse Sensor

• VCC connected to 5V of Arduino UNO
• GND connected to GND of Arduino UNO
• SIGNAL connected to A0 of Arduino UNO

SparkFun Soil Moisture Sensor

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

Soil Moisture Module

• VCC connected to 5V of Arduino UNO
• Ground connected to GND of Arduino UNO
• Analog connected to A1 of Arduino UNO
• positive connected to VCC of SparkFun Soil Moisture Sensor
• negative connected to GND of SparkFun Soil Moisture Sensor

16x2 I2C LCD

• VCC connected to 5V of Arduino UNO
• GND connected to GND of Arduino UNO
• SDA connected to A4 (SDA) of Arduino UNO
• SCL connected to A5 (SCL) of Arduino UNO

9V Battery

• + connected to Vin of Arduino UNO
• - connected to GND of Arduino UNO

Documented Code

Arduino UNO Code (sketch.ino)

void setup() {
  // put your setup code here, to run once:

}

void loop() {
  // put your main code here, to run repeatedly:

}

Note: The provided code for the Arduino UNO is a template and does not contain any functional code. It is expected that the user will fill in the setup and loop functions with code to initialize the sensors and LCD, read sensor data, and display the data on the LCD.