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.
| Tutorial | OOP/Pi Pico Concepts Covered |
|---|---|
| Lecture0 | • Introduction Projects • Wokwi • Wire your system |
| Lecture1 | • Unit Testing • UML Class Diagrams • Generalisation • Super/Sub Classes • Instantiation |
| Lecture2 | • Overriding Polymorphism • DRY • Encapsulation • Setter and Getters • Overloading Polymorphism |
| Lecture3 | • Abstraction • Non-Blocking |
| Lecture4 | • Pull Down Button • Interrupts |
| Lecture5 | • PWM • Stubs and Drivers |
| Lecture6 | • Multiple Inheritance • Association • Facade pattern • Subsystems |
| Lecture7 | • Open & Closed Loop Control Systems • State Machine |
Students will follow text-based instructions to build simple Pi Pico circuits and implement straightforward procedural programs to test their functionality. These activities will help students understand basic hardware connections and programming concepts while reinforcing their debugging skills.
All projects can be physically wired and tested (see components list) or simulated and programmed in the IDE of Wokwi.
- Connect and control a LED
- Connect a digital sensor that controls the LEDs
- Connect a analog sensor that controls the LEDs
- Control the brightness of the LED with Pulse Width Modulation
- Connect and control a servo motor
- Connect and read a ultrasonic sensor use it to control the servo motor
- Connect and control a I2C 16x2 LCD Display
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 | |
|---|---|
| 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 |
Students will follow text and video-based lectures to develop a pedestrian and traffic controller system using the Pi Pico. Through this system, they will learn a range of Object-Oriented Programming (OOP) concepts and practices, including encapsulation, inheritance, polymorphism, and abstraction. Additionally, students will explore hardware integration concepts such as GPIO pin control, PWM signals, and interrupt handling.
The lectures will guide them through building subsystems like traffic lights and pedestrian signals, implementing state machines, and understanding open-loop and closed-loop control systems. By the end of the course, students will have gained practical experience in designing, testing, and debugging both software and hardware components.
All projects can be physically wired and tested (see components list) or simulated and programmed in the IDE of Wokwi.
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 | |
|---|---|
| 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 |
classDiagram
class Pin {
-__pin: int
+__init__(pin: int)
+value()
+high()
+low()
+on()
+off()
+toggle()
}
class PWM {
-__pin: int
+__init__(pin: int)
+freq(freq: int)
+duty_u16(duty: int)
}
class Led_Light {
- __debug: bool
- __pin: int
- __flashing: int
- __last_toggle_time: float
+ Led_Light(pin, flashing=False, debug=False)
+ on()
+ off()
+ toggle()
+ flash()
+ led_light_state
+ led_light_state(value)
}
Pin <|-- Led_Light : Inheritance
class Pedestrian_Button {
- __pin: int
- __debug: bool
- __last_pressed: int
- __pedestrian_waiting: bool
+ Pedestrian_Button(pin, debug)
+ button_state() : bool
+ button_state(value)
+ callback(pin)
}
Pin <|-- Pedestrian_Button : Inheritance
class Audio_Notification {
- __debug: bool
- __last_toggle_time: floot
- __pin: int
+ Audio_Notification(pin, debug=False)
+ warning_on()
+ warning_off()
+ beep(freq=1000, duration=500)
}
PWM <|-- Audio_Notification : Inheritance
class TrafficLightSubsystem {
-__red: Led_Light
-__amber: Led_Light
-__green: Led_Light
-__debug: bool
+__init__(red: Led_Light, amber: Led_Light, green: Led_Light, debug: bool)
+show_red()
+show_amber()
+show_green()
}
Led_Light --> TrafficLightSubsystem : Association
class PedestrianSubsystem {
-__red: Led_Light
-__green: Led_Light
-__button: Pedestrian_Button
-__buzzer: Audio_Notification
-__debug: bool
+__init__(red: Led_Light, green: Led_Light, button: Pedestrian_Button, buzzer: Audio_Notification, debug: bool)
+show_stop()
+show_walk()
+show_warning()
+is_button_pressed() bool
+reset_button()
}
Led_Light --> PedestrianSubsystem : Association
Audio_Notification --> PedestrianSubsystem : Association
Pedestrian_Button --> PedestrianSubsystem : Association
class Controller {
-__traffic_lights: TrafficLightSubsystem
-__pedestrian_signals: PedestrianSubsystem
-__debug: bool
-__last_state_change: float
+state: string
+__init__(ped_red: Led_Light, ped_green: Led_Light, car_red: Led_Light, car_amber: Led_Light, car_green: Led_Light, button: Pedestrian_Button, buzzer: Audio_Notification, debug: bool)
+set_idle_state()
+set_change_state()
+set_walk_state()
+set_warning_state()
+set_error_state()
+update()
}
TrafficLightSubsystem --o Controller : Contains
PedestrianSubsystem --o Controller : Contains
| 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 Super Pin and PWM . |
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
