Flame Presence Sensor with Smart Pi One

In this guide, we will demonstrate how to read the values from a flame presence sensor connected to the Smart Pi One, using the SmartPi-GPIO library.

We will cover the following methods: - CLI commands - Python script

Required Materials

• Smart Pi One
• Flame presence sensor (e.g., DFRobot DFR0090 or similar)
• Connecting wires
• Breadboard (optional for easier connections)

Wiring Diagram

The flame presence sensor typically has three pins: VCC, GND, and DOUT (digital output).

• VCC connects to 5V (Pin 1).
• GND connects to Ground (Pin 6).
• DOUT connects to GPIOG11(Pin 7) to read the presence of flame.

Pin Number	Pin Name	Function
2	5V	Power Supply
7	GPIOG11	Flame Sensor Output (D0)
6	GND	Ground

Prerequisites: Configuration of smartpi-gpio

To install SmartPi-GPIO on your Smart Pi One, follow these steps:

1. Update system:

sudo apt update 
sudo apt-get install -y python3-dev python3-pip libjpeg-dev zlib1g-dev libtiff-dev
sudo mv /usr/lib/python3.11/EXTERNALLY-MANAGED /usr/lib/python3.11/EXTERNALLY-MANAGED.old

1. Clone the repository:

git clone https://github.com/ADNroboticsfr/smartpi-gpio.git
cd smartpi-gpio

1. Install the library:

sudo python3 setup.py sdist bdist_wheel
sudo pip3 install dist/smartpi_gpio-1.0.0-py3-none-any.whl

1. Activate GPIO interfaces:

sudo activate_interfaces.sh

Reading Values via CLI

You can read the values from the flame presence sensor using the CLI.

Steps:

1. Configure the pin for digital input:

sudo gpio 7 mode in

1. Read the value from the flame sensor:

sudo gpio 7 read

1. Example to read and display values continuously:

Use a loop to read the state of the flame sensor and print its value:

while true; do
  value=$(sudo gpio 7 read)
  echo "Flame Sensor Value: $value"
  sleep 1
done

This will display the current value read by the flame sensor every second.

Using Python

Reading Values with Python

With SmartPi-GPIO and Python, you can write a simple script to read the value from the flame presence sensor.

Steps:

1. Create a Python file:

nano flame_sensor_read.py

1. Write the following code:

from smartpi_gpio.gpio import GPIO
import time

# Initialize GPIO instance
gpio = GPIO()

# GPIO pin number for the flame sensor (GPIO7)
flame_sensor_pin = 7

# Configure the pin as input
gpio.set_direction(flame_sensor_pin, "in")

print("Reading values from the flame presence sensor...")

while True:
    # Read the value from the flame sensor
    value = gpio.read(flame_sensor_pin)
    print(f"Flame Sensor Value: {value}")
    time.sleep(1)  # Read every second

1. Save and exit (CTRL+X, Y, and Enter).

2. Run the Python script:

sudo python3 flame_sensor_read.py

This will continuously display the current value read by the flame presence sensor every second.