Python Scripts

Setup

Downloading the Demo Scripts

• Open a terminal
  • Your terminal will always opens to your home folder
  • if you type ls you will "list" the conents of that folder
• Paste this command into the terminal
  • git clone https://github.com/penguinrunner/Python-Raspberry-Pi-Scripts.git
• Open the your home folder with the file browser and you will see a folder named Python-Raspberry-Pi-Scripts
• Now you have the project files!

Installing Dependencies

• In a terminal copy and run this command
  • pip3 install RPi.GPIO
  • pip3 install flask
  • This just uses Python3's package manager to install some things we need.

Running the scripts

• All of the scripts are written for Python3 (not Python2 or Python2.7)
• In the terminal type cd Python-Raspberry-Pi-Scripts and you will enter that folder via the terminal
  • Remember you can type ls to see all the files in the terminal
• From here type python3 hello_world.py to run our first script
• If you see the output Hello world from the world of python! then it worked
• you can now run the rest of the scripts by typing python3 and then the name of the script!

Pinout

• red_button = 37
• green_button = 35
• red_led = 40
• green_led = 38
• For all LEDs I used a 220 ohm resister between the pin and the led
• For all the buttons I used a 10k ohm resistor between the button and the pin
• 3.3v Was used as the input voltage for the buttons from pin 1
• You can use any GND pin for the negative Rail for the LEDs (Pins 6,9,14,20,25,30,39)
• LCD PINS: 5V, GND, 3 and 6
• HC-SR04 Sensor Pins: 5v(vcc), GND, 16 (trig), 18 (echo)

Outputs

• Blink Led 1

  • General Setup of the script
  • Import needed libraries
  • Setup pin as an output
  • Turn the output on and off

• Blink Led 2

  • General Setup of the script
  • Import needed libraries
  • Setup pins as an outputs
  • Turn the output on and off
  • Uses two outputs

Inputs

• Button Press 1

  • Basics of detecting an input on a GPIO pin

• Button Press 2

  • Basics of detecting an input on a GPIO pin
  • Control an output based on the input

• Button Press 3

  • Basics of detecting an input on a GPIO pin
  • Control an output based on the input
  • Non Blocking code while controlling each input/output

• Button Press 3

  • Basics of detecting an input on a GPIO pin
  • Control an output based on the input
  • Non Blocking code while controlling each input/output

• Button Press 4 (Can be skipped)

  • Basics of detecting an input on a GPIO pin
  • Control an output based on the input
  • Non Blocking code while controlling each input/output
  • Display which button is pressed on 1602A LCD Display

• Button Press 5

  • Basics of detecting an input on a GPIO pin
  • Control an output based on the input
  • Non Blocking code while controlling each input/output
  • Detect both the Rising and Falling of the input and control an out accordingly

Sonar HC-SR04 Sensor

• Measure distance with sound waves
• Calculates distance based on how long a sound wave takes to come back
• Ultrasonic1 and Ultrasonic Freenove are the same file
  • One uses functions and the other is simplified into a single loop

Flask Web Server

• Flask Led 1
  • Uses a python Library called "Flask" to create a web server
  • Uses "Routes" to decide which function you are asking for
    • uses whatever you put after the server address as the route
    • EX: 192.168.1.50/home would look for the route "home"
  • Has 3 different functions & Routes
    • Function 1 "hello_world"
      • Just returns a text back to the web browser
    • Function 2 "hello_template"
      • Returns a preconfigured HTML file back to the browser
    • Function 3 "led_control"
      • Adds a form to our HTML template
      • Lets us send information back to our program
      • When our program receives the information, it can do something with it (Like turn the led on or off)
      • Also lets us pass dynamic (changing) data to our template

LCD Display

• Coming Soon

RGB LED

• Coming Soon