MicroPython OOP Pi Pico Mini Project

This repository is a series of introduction tasks to teach students the basics of Pi Pico and common mechatronic components. Then students will create a mini OOP based project to explicitly teach Object Oriented Paradigm (OOP) programming concepts specifically in the microcontroller context.

Students will be recreating a model of the pedestrian crossing on Unwins Bridge Road out the front of Tempe High School.

Introduction to Pi Pico & Common Mechatronic Commonents

Projects

1. Connect and control a LED
2. Connect a digital sensor that controls the LEDs
3. Connect a analog sensor that controls the LEDs
4. Control the brightness of the LED with Pulse Width Modulation
5. Connect and control a servo motor
6. Connect and read a ultrasonic sensor use it to control the servo motor
7. Connect and control a I2C 16x2 LCD Display

Components

Note

Students can build using physical components or prototype using this Template Wokwi Project.

• Breadboard
• Jumper leads
• Pi Pico
• 1x LED
• 1x 130Ω resistors
• 1x Potentiometer or analog sensor
• 1x Momentary switch or digital sensor
• 1x Servo motor
• 1x Ultrasonic sensor
• 1x 2IC 16x2 LCD Display

Pin Allocation

Pin
GP0	SDA
GP1	SCL
GP4	Keyboard Interrupt
GP10	Servo Motor Signal
GP11	Ultrasonic Echo Signal
GP12	Ultrasonic Trig Signal
GP13	Digital Sensor Signal
GP15	External LED
GP25	Inbuilt LED
GP26	Analog Sensor Signal
AGND	Analog Ground
GND	Ground
3V3	3V Power
VBUS	5V Power

OOP Mini Project

Final Product

Wire your system

Components

Note

Students can build using physical components or prototype using this Template Wokwi Project.

• Breadboard
• Jumper leads
• Pi Pico
• 1x Momentary switch
• 5x LED
• 1x Piezo buzzer
• 5x 130Ω resistors

Pin allocation

Pin
GP3	Red LED
GP4	Keyboard Interrupt
GP5	Amber LED
GP7	Red LED
GP17	Flashing Green LED
GP19	Flashing Red LED
GP22	Button signal
GP27	Piezo Buzzer
GND	Circuit Ground
3V3	Button logic voltage

Final UML Diagram

classDiagram
    class Pin {
        -__pin: int
        +__init__(pin: int)
        +value()
        +high()
        +low()
        +toggle()
    }

    class PWM {
        -__pin: int
        +__init__(pin: int)
        +freq(freq: int)
        +duty_u16(duty: int)
    }

    class Audio_Notification {
        -__debug: bool
        +__init__(pin: int, debug: bool)
        +warning_on()
        +warning_off()
        +beep(freq: int, duration: int)
    }
    PWM <|-- Audio_Notification : Inheritance

    class Led_Light {
        -__debug: bool
        -__pin: int
        -__flashing: bool
        +__init__(pin: int, flashing: bool, debug: bool)
        +on()
        +off()
        +toggle()
        +flash(duration: int)
        +on_for(duration: int)
        +led_light_state: int
    }
    Pin <|-- Led_Light : Inheritance

    class Pedestrian_Button {
        -__debug: bool
        -__pin: int
        -__last_pressed: int
        -__pedestrian_waiting: bool
        +__init__(pin: int, debug: bool)
        +callback(pin: Pin)
        +button_state
        +reset
    }
    Pin <|-- Pedestrian_Button : Inheritance

    class Controller {
        -__object: Led_Light
        -__object: Led_Light
        -__object: Led_Light
        -__object: Led_Light
        -__object: Led_Light
        -__object: Pedestrian_Button
        -__object: Audio_Notification
    }

    Led_Light --> Controller : Composition
    Audio_Notification --> Controller : Composition
    Pedestrian_Button --> Controller : Composition

Loading

Note

Inheritance and association labels are note required in a UML diagram but have been added for understanding.

Script Versions Provided

Version	Notes
v01.py	Basic "Blink" Program (the Hello World of mechatronics) for Unit Testing the Microcontroller.
v02.py	Unit Test for wiring and use basic methods from parent Pin and PWM class.
v03.py	A blank python script.

MicroPython_OOP_Pi_Pico_Mini_Project_Source and MicroPython_OOP_Pi_Pico_Mini_Project_Template by Ben Jones is licensed under Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International