Week 27 28 29

WEEK 27-28-29

1. I have improved two example videos to load the program to physical tello in python and in scratch for the channel kibotics.
   • For Python => Simple Tello exercise tutorial with Python
   • For Scratch => Simple Tello exercise tutorial with Scratch
2. I have continued investigating how to achieve the integration of the tello drone from kibotics with MacOs and Windows. Check if with PyInstaller you could only make the self-contained file without entering the python interpreter, which is what gives problems when not allowing a cross compilation, but I have not see the way to do it by this method. I have found a possible way to do it for windows, by using wine:
   • Wine (recursive backronym for Wine Is Not an Emulator) is a free and open-source compatibility layer that aims to allow computer programs (application software and computer games) developed for Microsoft Windows to run on Unix-like operating systems. Wine also provides a software library, known as Winelib, against which developers can compile Windows applications to help port them to Unix-like systems
   • The idea would be to use pyinstaller previously installed inside wine and to be able to run it from there.

     $ wine python.exe Scripts/pip.exe install pyinstaller
     

   • I have tried integrating it in kibotics-web server and it is able to get the .exe, but it fails when executing it because it is not integrating the necessary library. I will try to investigate further how to fix this bug.
   • Disadvantages of using wine:
     • It requires previously installing wine on the machine where the server is running.
   • References:
     • https://www.it-swarm.dev/es/python/como-creo-un-ejecutable-de-windows-con-pyinstaller-en-ubuntu/960967170/
     • http://www.python.org.ar/wiki/Recetario/CrearEjecutableWindowsDesdeLinux
     • https://www.it-swarm.dev/es/python/compilacion-cruzada-de-un-script-python-en-linux-en-un-ejecutable-de-windows/969633203/
3. I have started to study how the flask library works to use it with the raspberry pi. I have made an example that consists of turning on two LEDs from a web page.
   • Video with the example
   • Sample code:

       import RPi.GPIO as GPIO
       from flask import Flask, render_template, request
       app = Flask(__name__)
     
       GPIO.setmode(GPIO.BCM)
     
       # Create a dictionary called pins to store the pin number, name, and pin state:
       pins = {
          23 : {'name' : 'GPIO 23', 'state' : GPIO.LOW},
          24 : {'name' : 'GPIO 24', 'state' : GPIO.LOW}
          }
     
       # Set each pin as an output and make it low:
       for pin in pins:
          GPIO.setup(pin, GPIO.OUT)
          GPIO.output(pin, GPIO.LOW)
     
       @app.route("/")
       def main():
          # For each pin, read the pin state and store it in the pins dictionary:
          for pin in pins:
             pins[pin]['state'] = GPIO.input(pin)
          # Put the pin dictionary into the template data dictionary:
          templateData = {
             'pins' : pins
             }
          # Pass the template data into the template main.html and return it to the user
          return render_template('main.html', **templateData)
     
       # The function below is executed when someone requests a URL with the pin number and action in it:
       @app.route("/<changePin>/<action>")
       def action(changePin, action):
          # Convert the pin from the URL into an integer:
          changePin = int(changePin)
          # Get the device name for the pin being changed:
          deviceName = pins[changePin]['name']
          # If the action part of the URL is "on," execute the code indented below:
          if action == "on":
             # Set the pin high:
             GPIO.output(changePin, GPIO.HIGH)
             # Save the status message to be passed into the template:
             message = "Turned " + deviceName + " on."
          if action == "off":
             GPIO.output(changePin, GPIO.LOW)
             message = "Turned " + deviceName + " off."
     
          # For each pin, read the pin state and store it in the pins dictionary:
          for pin in pins:
             pins[pin]['state'] = GPIO.input(pin)
     
          # Along with the pin dictionary, put the message into the template data dictionary:
          templateData = {
             'pins' : pins
          }
     
          return render_template('main.html', **templateData)   
     
       if __name__ == "__main__":   
          app.run(host='0.0.0.0', port=80, debug=True)   
     

   • References:
     • https://randomnerdtutorials.com/raspberry-pi-web-server-using-flask-to-control-gpios/
     • https://www.programoergosum.es/tutoriales/control-de-gpio-con-flask-en-raspberry-pi/